CÁC NHÂN tố tác ĐỘNG đến đổi mới SÁNG tạo của NHÓM TRONG LĨNH vực DỊCH vụ bán lẻ BẰNG CHỨNG từ VIỆT NAM

INTRODUCTION

Research gaps

Team innovation, defined as the development and implementation of novelty (van Knippenberg, 2017), is crucial for organizations to gain a competitive advantage and thrive in today's fast-paced and unpredictable market (Acar, Tarakci, & van Knippenberg, 2019) Key perspectives in team innovation research include knowledge integration, team climate, aggregation of individual inputs, and leadership (Hülsheger, Anderson, & Salgado, 2009; Rosing, Frese, & Bausch, 2011; Anderson, Potočnik, & Zhou, 2014; van Knippenberg, 2017) The relationship between leadership and innovation has been extensively studied, highlighting its significance at the team level (Rosing et al., 2011; Hughes et al., 2018).

Prior empirical research linking leadership and team innovation has implicated a variety of leadership styles such as transformational leadership (Jiang & Chen,

Various leadership styles, including authentic leadership, shared leadership, servant leadership, and ambidextrous leadership, significantly influence social processes like team learning, impacting team innovation under specific conditions However, existing empirical studies on these leadership styles reveal notable gaps that need further exploration.

Research on ambidextrous leadership's impact on team learning and innovation has been largely overlooked, both in transitioning economies like Vietnam and in advanced economies.

A significant trend in the retail service industry is the emphasis on cultivating long-term customer relationships rather than merely pursuing short-term sales By prioritizing individualized attention and enhancing service quality, retail teams can foster innovation and create more meaningful connections with their customers (Subramony & Pugh, 2015).

Ambidextrous leadership refers to the ability to promote both explorative and exploitative behaviors among followers by adjusting behavioral variance and seamlessly transitioning between these behaviors (Rosing et al., 2011) Research indicates that ambidextrous leadership positively influences innovation through individual-level employee exploration and exploitation behaviors (Zacher et al., 2016) Additionally, differences in team performance have been linked to factors such as team leadership, learning, and psychological safety (Edmondson, 1999; Kostopoulos & Bozionelos, 2011; Zacher & Rosing, 2015), with some studies examining the role of team social processes and leadership in fostering team innovation (Hülsheger et al., 2009; Rosing et al., 2011; Anderson et al., 2014; van Knippenberg, 2017).

Inclusive leaders significantly motivate diverse employees to innovate by fostering an environment characterized by openness, accessibility, and a sense of belonging (Randel et al., 2018; Carmeli et al., 2010) This leadership style enhances key job outcomes, including taking charge behavior and voice behavior, ultimately contributing to a more dynamic and creative workplace (Zeng et al., 2020; Guo et al., 2018).

Recent studies have explored the impact of inclusive leadership on creativity and innovation across various organizational levels, including individual, team, and organizational perspectives (Choi et al., 2017; Gong et al., 2021; Javed et al., 2018; Javed et al., 2019; Siyal et al., 2021; Ye et al., 2019) Additionally, research has examined concepts such as prosocial rule breaking (Wang & Shi, 2021) and psychological distress (Ahmed et al., 2020) within this context.

Research on the impact of inclusive leadership on team-level innovation remains limited, despite calls for further investigation (Van Knippenberg and Van Ginkel, 2021) Several studies have begun to address this gap by exploring various mediators and moderators For instance, Ye, Wang, and Guo (2019) analyzed how team voice mediates and performance pressure moderates the relationship between inclusive leadership and team innovation Leroy et al (2021) focused on the mediating effect of team-derived inclusion on the connection between inclusive leadership and team creativity Additionally, Ashikali, Groeneveld, and Kuipers (2020) examined how inclusive leadership moderates the relationship between team ethnic-cultural diversity and an inclusive climate However, the roles of shared team psychological contract fulfillment and team proactive personality in the context of inclusive leadership and team innovation remain unexplored.

This thesis explores the application of social exchange theory (SET) within teams, focusing on whether shared team psychological contract fulfillment acts as a mediator in the relationship between team dynamics and performance Shared team psychological contract fulfillment refers to the alignment of team members' perceptions regarding the organization's obligations to the team Additionally, it investigates how teams characterized by proactive personality traits are more inclined to generate and implement innovative ideas, ultimately enhancing workplace outcomes Furthermore, the study examines the moderating effect of team proactive personality on the relationship between inclusive leadership and shared team psychological contract fulfillment.

There is currently a limited understanding of how team psychological capital (PsyCap) influences learning and innovation at the team level PsyCap is defined as an individual's development state characterized by psychological resources such as self-efficacy, hope, optimism, and resilience (Luthans et al., 2007) Initially, PsyCap was conceptualized at the individual level (Luthans et al., 2015), and most research has primarily focused on this aspect (e.g., Luthans et al., 2008; Miao et al., 2020; Nguyen & Nguyen, 2012) However, recent studies highlight the growing need to explore PsyCap in the context of team processes and performance (Chou et al., 2008; Gundlach et al.).

Since 2006, researchers have increasingly focused on the concept of Psychological Capital (PsyCap) at the team level Team-level PsyCap is defined as the consensus among team members regarding their shared perceptions of PsyCap within the team.

Prior research has highlighted the significance of team Psychological Capital (PsyCap) in various outcomes, including organizational citizenship behavior, team performance, satisfaction, service quality, customer satisfaction, organizational commitment, and creativity However, despite the critical importance of team innovation for the survival and growth of modern organizations, the connection between team PsyCap and team innovation remains largely unexplored.

The process of knowledge creation and learning in organizations predominantly occurs within teams, as highlighted by Edmondson and Nembhard (2009) However, our comprehension of how team psychological capital (PsyCap) influences team learning and innovation remains insufficient This thesis aims to explore this relationship by applying the theory of psychological capital, as proposed by Youssef-Morgan and Luthans (2013), within the context of teams, as discussed by Dawkins et al.

A study conducted in 2015 explored the influence of team psychological capital (PsyCap) on team innovation, highlighting the mediating effects of team learning It specifically focused on both exploratory and exploitative learning as critical components in the relationship between team PsyCap and innovation outcomes.

Research objectives

There are three main objectives in this thesis:

Objective 1: The impact of ambidextrous leadership on both team exploratory and exploitative learning and, subsequently, on team innovation (Study 1).

Objective 2: The impact of inclusive leadership on shared team psychological contract fulfillment and, subsequently, on team innovation, and the impact of team proactive personality on the relationship between inclusive leadership and shared team psychological contract fulfillment (Study 2).

Objective 3: The impact of team PsyCap on team exploratory and exploitative learning and, subsequently, on team innovation (Study 3).

Based on three main objectives, this thesis directly answers some specific research questions:

1 What is the nature of relationship between two types of leadership (i.e., ambidextrous leadership and inclusive leadership) and innovation at the team level of analysis?

2 What is the mediating mechanisms (i.e., team learning, shared team psychological contract fulfillment) between two types of leadership and innovation of team level of analysis?

3 How does team proactive personality influence the inclusive leadership- shared team psychological contract fulfillment relationship?

Research context

Vietnam's retail sector is experiencing significant growth, driven by the expansion of both physical and digital trade channels From 2013 to 2018, the sector achieved a compound annual growth rate (CAGR) of approximately 10.97%, with total revenues reaching around US$ 142 billion in 2018 and US$ 214.8 billion in 2019 Forecasts indicate that Vietnam will become the fastest-growing market for convenience stores in Asia by 2021, boasting a remarkable CAGR of 37.40% Key cities like Ho Chi Minh City and Hanoi contribute about 33% of total retail sales, characterized by store expansion, fierce competition between local and international retailers, and the rising popularity of mini-supermarkets, positioning these markets for substantial growth.

Research in retail services is crucial for enhancing the market potential in Vietnam, as contemporary firms can benefit significantly from innovation through effective team leadership Store leaders play a vital role in boosting team activities and fostering a culture of learning, which can lead to a competitive advantage By implementing efficient learning strategies, these leaders enable their teams to acquire valuable knowledge from customer interactions As frontline employees with authority, store leaders face the challenge of meeting customer expectations and are tasked with seeking new knowledge to enhance team performance.

Data collection

Data collection for this study was conducted by a research agency based in Ho Chi Minh City, with a representative office in Hanoi, under the guidance of the thesis author The objective was to gather data on retail services to validate measurement tools and test hypotheses The target respondents were store leaders with a minimum of six months of experience in their current roles, ensuring they possessed a comprehensive understanding of store operations and effective communication with their teams This approach aligns with the use of key informants as recommended by Kumar et al (1993) A partial self-administered method was utilized, where interviewers distributed questionnaires to willing store leaders and collected them upon completion.

If any questionnaires contained missing values, interviewers invited store leaders to complete them.

Structure of the thesis

This thesis includes six Chapters with Figures, Tables and Appendixes, as follow:

Chapter 1 presents research gaps, research objectives and research context. Chapter 2 discusses about literature review and overall model, including theoretical background, conceptual model, design, sample and measurement.

Chapter 3 investigates the role of ambidextrous leadership and team learning in team innovation.

Chapter 4 examines the role of inclusive leadership, shared team psychological contract fulfillment, team proactive personality in team innovation. Chapter 5 investigates the role of team PsyCap and team exploratory and exploitative learning in team innovation.

Chapter 6 discusses about conclusion, including summary, theoretical implications, practical implications, limitations and future directions.

LITERATURE REVIEW AND OVERALL MODEL

Theoretical background

This thesis investigates the factors that drive team innovation through a conceptual framework that integrates multiple theories, including ambidextrous leadership for innovation, social exchange theory (SET) in teams, and psychological capital (PsyCap) theory.

2.1.1 The theory of ambidextrous leadership for innovation

The ambidextrous leadership theory highlights the importance of team leaders' opening and closing behaviors in driving innovation within teams (Rosing et al., 2011) Opening behaviors, which encourage experimentation and independent thinking, promote exploration activities, while closing behaviors, which focus on setting guidelines and monitoring performance, foster exploitation activities Recent studies, such as those by Zacher and Rosing (2015), demonstrate that while closing behaviors have minimal impact on team innovation, opening behaviors and their interaction with closing behaviors significantly enhance innovation outcomes Additionally, Zacher et al (2016) found that leader behaviors positively influence employee exploration and exploitation, which are directly linked to self-reported innovative performance.

The ambidextrous leadership theory emphasizes the importance of direct interactions between team leaders and members in retail service stores, where leaders exhibit complementary behaviors of opening and closing to foster innovation (Rosing et al., 2011) These leaders not only engage with customers as frontline service employees but also motivate their teams to leverage their insights for effective goal-setting By understanding customer needs and persistent service challenges, frontline teams contribute valuable knowledge, creating a unique competitive advantage (Ye et al., 2012) This approach enhances communication and collaboration among team members, facilitating goal achievement and team learning to boost performance (Kostopoulos & Bozionelos, 2011; Ye et al., 2012) Ultimately, the interplay of opening and closing behaviors in ambidextrous leadership is crucial for promoting both exploratory and exploitative learning, thereby driving innovation in the retail service environment.

2.1.2 Social exchange theory in groups

Social Exchange Theory (SET) is a crucial framework in management and organizational behavior research, utilized to analyze and forecast employee attitudes and behaviors (Cropanzano & Mitchell, 2005; Kutaula et al., 2020; Lavelle et al., 2007; Tse et al., 2013; Wang et al., 2020) It delineates the distinctions between economic and social exchanges, as originally proposed by Blau in 1964.

Economic exchange involves short-term transactions of tangible resources between employees and employers, whereas social exchange emphasizes long-term interactions centered on intangible resources such as socioemotional support, mutual trust, and commitment.

While Social Exchange Theory (SET) primarily addresses individual employee attitudes and behaviors, it is essential to recognize that employees often collaborate in teams to achieve their goals Interactions and information-sharing within teams can lead to shared perceptions regarding contributions and rewards SET suggests that when employees feel supported, they cultivate high-quality social exchange relationships with their teams and other organizational members This perception fosters feelings of gratitude, obligation, and trust, which in turn motivate employees to reciprocate with positive workplace behaviors, such as creativity, innovation, and both in-role and extra-role contributions.

Recent studies have utilized Social Exchange Theory (SET) to explore the connections between inclusive leadership and its effects on attitudes and behaviors at both organizational and individual levels (Ahmed et al., 2020; Eva et al., 2020; Gong et al., 2021) Notably, creativity and innovation are significant outcomes of this relationship (Choi et al., 2017; Javed et al., 2018; Siyal et al., 2021) Research has also examined various mediators and moderators that influence the link between inclusive leadership and innovation, such as person-job fit, psychological empowerment, leader-member exchange, psychological safety, psychological capital, and intrinsic motivation Furthermore, inclusive leadership has been found to have a positive impact on creativity and innovation at the team level (Leroy et al., 2021; Ye et al., 2019).

PsyCap, or psychological capital, is an individual's positive psychological state characterized by four key components: confidence (efficacy) to tackle challenging tasks, a positive outlook (optimism) about future success, the ability to persevere and adapt (hope) towards achieving goals, and resilience to recover and thrive in the face of adversity Research indicates that PsyCap is significantly linked to favorable employee attitudes, behaviors, and performance outcomes.

2012), as well as employee innovation (e.g., Luthans et al., 2011; Hsu & Chen, 2017).

Team PsyCap is defined as a collective psychological state encompassing self-efficacy, hope, optimism, and resilience, as outlined by Heled, Somech, and Waters (2016) While individual PsyCap represents a personal psychological resource developed throughout one’s work and life, team PsyCap emerges from the shared perceptions and interactions among team members (Luthans & Youssef-Morgan, 2017; Dawkins et al., 2015).

Conceptual model

This thesis presents a conceptual model that illustrates the relationships between ambidextrous and inclusive leadership behaviors and various social processes, including team PsyCap, exploratory and exploitative learning, shared psychological contract fulfillment, and proactive personality, all of which contribute to team innovation Additionally, the model incorporates team leaders' gender, team size, and team tenure as control variables Detailed hypotheses for each study will be outlined in the subsequent chapters.

Figure 1 Overall model of thesis

AMBIDEXTROUS LEADERSHIP AND TEAM LEARNING

Understanding team innovation is essential for the survival and growth of modern organizations, prompting ongoing interest from both academic researchers and practitioners This research encompasses various topics, including team structure, composition, climate, processes, knowledge integration, and leadership Recently, the focus has shifted towards ambidextrous leadership as a key approach to fostering team innovation.

Ambidextrous leadership refers to the capacity to encourage both explorative and exploitative behaviors among followers by adjusting their behavioral variance and seamlessly transitioning between these behaviors (Rosing et al., 2011) Research has linked ambidextrous leadership to innovation, highlighting various mediating factors such as individual employee exploration and exploitation behaviors (Zacher et al., 2016) At the team level, studies have examined how team performance is influenced by factors like team leadership, learning, and psychological safety, with an emphasis on social processes and leadership's role in fostering team innovation (Hülsheger et al., 2009; Anderson et al., 2014; van Knippenberg, 2017) Notably, Edmondson (1999) explored the impact of team learning behaviors on performance, while Kostopoulos and Bozionelos (2011) focused on the significance of team exploratory and exploitative actions.

TEAM INNOVATION IN RETAIL SERVICES: THE ROLE OF

Introduction

Understanding team innovation is essential for the survival and growth of modern organizations, sparking ongoing interest among researchers and practitioners (West & Farr, 1990; Hülsheger et al., 2009; Anderson et al., 2014; van Knippenberg, 2017; Hughes et al., 2018) This research encompasses various aspects, including team structure, composition, climate, processes, knowledge integration, and leadership (Anderson et al., 2014; van Knippenberg, 2017) Recently, the focus has shifted towards ambidextrous leadership as a key approach to fostering team innovation (Rosing et al., 2011; Anderson et al., 2014; Zacher & Rosing, 2015; van Knippenberg, 2017).

Ambidextrous leadership is defined as the ability to promote both explorative and exploitative behaviors among followers by adjusting behavioral variance and flexibly transitioning between these behaviors (Rosing et al., 2011) Previous research has linked ambidextrous leadership to innovation, highlighting various mediating factors such as employee exploration and exploitation at the individual level (Zacher et al., 2016) At the team level, studies have explored how team performance is influenced by leadership, learning, and psychological safety, with a focus on social processes and leadership's role in fostering innovation (Hülsheger et al., 2009; Anderson et al., 2014; van Knippenberg, 2017) Notably, Edmondson (1999) examined team learning behavior's impact on performance, while Kostopoulos and Bozionelos (2011) focused on exploratory and exploitative learning Additionally, Zacher and Rosing (2015) investigated the interplay of opening and closing leadership behaviors and their effect on team innovation However, the role of ambidextrous leadership in team learning and innovation remains underexplored, particularly in both transitioning economies like Vietnam and advanced economies.

A growing trend in the retail service industry emphasizes the importance of fostering long-term customer relationships over merely achieving short-term sales Retail service teams are increasingly dedicated to enhancing service quality by offering personalized attention to customers, which in turn creates opportunities for team innovation (Subramony & Pugh, 2015).

Study 1 explores the influence of ambidextrous leadership on team learning and innovation within the retail service sector, based on the ambidexterity theory of leadership for innovation Analyzing survey data from 296 team leaders in Vietnam, the study confirms the positive relationships between team leadership, exploratory and exploitative learning, and team innovation These findings enhance the understanding of facilitators of team innovation and provide empirical support for the ambidexterity theory in a transitioning economy The paper also outlines the theoretical framework, hypotheses, research methodology, data analysis, and discusses the implications, limitations, and future research directions.

Theoretical background and hypotheses

Recent studies have explored the crucial role of leadership in fostering innovation, highlighting the connection between different leadership styles and team innovation (Eisenbeiss et al., 2008; Hoch, 2013; Hughes et al., 2018) While various leadership styles, including ambidextrous, authentic, transformational, and transactional leadership, have been examined, ambidextrous leadership has been notably under-researched Table 1 presents a summary of significant empirical studies that illustrate the relationship between leadership styles and innovation at the team level.

Table 1 A summary of empirical studies on the relationship between leadership styles and team innovation

Authors Sample Main findings Černe et al (2013)

Twenty three team leaders and 289 team members of a Slovenian manufacturing and processing firm in Slovenia

Perceived authentic leadership was positively related to team innovation, but self-ascribed authentic leadership was not.

Ninety five research and development team

(R&D) leaders and 428 team members of

33 firms from various industries in China

Transformational leadership was positively related to support for innovation climate, but was not significantly related to team innovation Support for innovation climate was positively related to team innovation.

Thirty three R&D team leaders and 188 team members of one research institute and four international R&D companies engaged in the automotive, semiconductor, packaging, and scientific instruments industries (country was not reported)

Transformational leadership was positively related to support for innovation, which in turn interacted with climate for excellence to enhance team innovation

Forty three team leaders and 184 team members of 43 teams in the fields of product development and training in two different companies (country was not reported)

Shared leadership and vertical transformational and empowering leadership were positively related to team innovative behavior

Sample 1: 44 teams in a biopharmaceutical firm in China

Sample 2: 76 teams (76 team leaders and

414 team members) in 29 companies from various industries in China

An integrative mechanism (i.e., cooperative norms  within-team knowledge sharing) mediated the influence of transformational leadership on team innovative performance.

(2011) Eighty five team leaders and 450 team members of eight organizations from various fields in China

The interaction between transactional leadership and emotional labor negatively affected team innovativeness

Fifty two team leaders and 301 team members of 52 firms from various industries in Taiwan

Team knowledge sharing intention fully mediated the impact of transformational leadership climate on team innovation.

Sixty team leaders and 280 team members in the healthcare industry in United

Inspirational leadership significantly enhances team innovation by fostering a positive mood, particularly when professional salience is high However, this effect diminishes when professional salience is low, indicating that the impact of inspirational leadership on innovation is contingent upon the level of professional engagement within the team.

(2019) Sample 1: 41 team leaders and 163 team members in the fields of medical devices and banking in China.

Sample 2: 66 team leaders and 406 team members in the field of software development in China

Inclusive leadership fosters team innovation by enhancing team voice, particularly under performance pressure The interaction between inclusive leadership and performance pressure significantly boosts team innovation, with team voice serving as a complete mediator in this relationship.

One hundred and fifty four team leaders and 425 team members in the fields of finance, heavy manufacturing, and telecommunications in Indonesia and

Prototypicality fully mediated the impact of servant leadership on team innovation.

Thirty three team leaders and 90 team members in the fields of architectural and interior design firms in Australia

Research indicates that while closing leadership behavior does not significantly impact team innovation, opening leadership behavior, along with the interaction between closing and opening leadership behaviors, positively influences team innovation.

The theory of ambidextrous leadership for innovation suggests that the opening and closing behaviors of team leaders significantly influence team innovation (Rosing et al., 2011) Opening leadership behaviors encourage experimentation and independent thinking, promoting exploration, while closing behaviors focus on reducing variation and enforcing guidelines, fostering exploitation Recent research has applied this theory in various contexts, such as Zacher and Rosing's (2015) study in the architecture industry, which found that opening behaviors and their interaction with closing behaviors positively impacted team innovation, whereas closing behaviors alone did not Additionally, Zacher et al (2016) demonstrated that leaders' opening and closing behaviors positively affected employee exploration and exploitation, which in turn enhanced employees' self-reported innovative performance.

The ambidextrous leadership theory emphasizes the importance of direct and frequent interactions between team leaders and members, particularly in retail service settings (Rosing et al., 2011) In this context, team leaders exhibit two complementary behaviors—opening and closing—that foster innovation among their teams By engaging as frontline service employees, they not only interact with customers but also motivate team members to align their efforts with the store's objectives, leveraging their insights from daily operations This direct engagement allows service teams to gather valuable knowledge about customer needs and service delivery challenges, creating a unique competitive advantage (Ye et al., 2012) As a result, store leaders can enhance communication and collaboration among team members, facilitating goal-setting and promoting team learning to boost performance This dual approach effectively captures and transforms knowledge, ultimately maximizing team effectiveness (Wyer et al., 2010; Kostopoulos & Bozionelos, 2011).

According to Ye et al (2012), the ambidextrous leadership theory for innovation highlights the significance of leaders' opening and closing behaviors, as well as their interplay, in fostering both exploratory and exploitative learning within retail service teams, ultimately driving innovation.

The conceptual model illustrated in Figure 2 highlights the connections between leadership behaviors and team learning, specifically focusing on team exploratory and exploitative learning, as well as the link between team learning and team innovation Team exploratory learning emphasizes the importance of seeking new knowledge and experiences, which fosters a culture of innovation within the team.

According to Kostopoulos and Bozionelos (2011), team exploratory activities involve searching, experimenting, and developing new ideas and task-related capabilities, while team exploitative activities focus on refining, recombining, and implementing existing knowledge and skills The model suggests that opening leadership behaviors enhance team exploratory learning, whereas closing leadership behaviors positively influence team exploitative learning.

The interplay between opening and closing leadership behaviors positively influences team exploratory and exploitative learning, which in turn fosters team innovation.

Figure 2 Conceptual model of Study 1

Opening leadership behaviour*Closing leadership behavior

3.2.2.1 Opening leadership behavior and team exploratory learning

According to the ambidextrous leadership theory, store leaders who exhibit open leadership behaviors can foster a culture of exploration and experimentation within their teams, enabling the transformation of frontline knowledge into valuable explicit knowledge (Ye et al., 2012) This approach enhances team learning and provides a competitive advantage in retail services Leaders who demonstrate higher levels of openness are better equipped to implement effective learning strategies that facilitate knowledge acquisition from customer interactions As frontline employees with authority, store leaders face the challenge of meeting customer expectations and must seek new knowledge to enhance team performance.

H1 Opening leadership behavior has a positive effect on team exploratory learning.

3.2.2.2 Closing leadership behavior and team exploitative learning

Teams that prioritize exploration of evolving customer needs may incur experimentation costs without tangible benefits A leader's closing behaviors can encourage team members to concentrate on routine tasks, leveraging existing knowledge and skills while discouraging risk-taking In retail services, store leaders exhibiting strong closing behaviors tend to promote exploitative learning, equipping their teams with effective strategies for knowledge acquisition through the integration of current skills These leaders often exhibit satisfaction with existing knowledge and a reluctance to embrace mistakes, which can further reinforce a focus on efficiency over innovation.

H2 Closing leadership behavior has a positive effect on team exploitative learning.

3.2.2.3 The interaction effect between opening and closing leadership behaviors

The ambidextrous leadership theory emphasizes the importance of specific leadership behaviors tailored to the intricate nature of innovation processes Our model suggests that the dynamic interplay between opening and closing leadership behaviors can boost followers' explorative and exploitative activities Team leaders must adeptly alternate between these behaviors to effectively address varying innovation demands.

The interplay of opening and closing leadership behaviors reflects the concept of ambidexterity, which has been associated with enhanced innovation in team dynamics (Zacher & Rosing, 2015).

H3 The interaction between opening and closing leadership behaviors has a positive effect on team exploratory learning.

H4 The interaction between opening and closing leadership behaviors has a positive effect on team exploitative learning.

3.2.2.4 Team exploratory learning and innovation

Innovation is defined as the deliberate introduction and application of new ideas, processes, products, or procedures within a group or organization, aimed at providing significant benefits to individuals, teams, or society at large (West & Farr, 1990) In this context, team innovation encompasses a team's ability to generate creative and original ideas, as well as the capacity to implement these ideas effectively to achieve positive results (Zacher & Rosing).

Research methods

Vietnam's retail sector is experiencing significant growth, focusing on both modern physical channels like commercial centers and convenience stores, as well as digital platforms From 2013 to 2018, the sector achieved a compound annual growth rate (CAGR) of approximately 10.97%, generating total revenue of around $142 billion in 2018 By 2021, Vietnam is projected to become the fastest-growing market for convenience stores in Asia, with an impressive CAGR of 37.40% Major cities like Ho Chi Minh City and Hanoi play a crucial role, accounting for about 33% of total retail sales, characterized by rapid store expansion, fierce competition between local and international retailers, and a growing popularity of mini-supermarkets, positioning the convenience market for substantial growth.

Study 1 adopted a phased approach by undertaking a pilot study and a main survey in Ho Chi Minh City, the major business center, and in Hanoi, the capital of Vietnam Survey respondents were team leaders with at least 6 months’ experience in the current position In the pilot study, we first conducted two in-depth interviews with store leaders in Ho Chi Minh City to evaluate the contents of the measures and to examine how respondents described existing ambidexterity leadership and team exploratory and exploitative learning Although the measures of all constructs in Study 1 were available in the literature, this step was crucial to ensure the appropriateness of the measures to the retail service context in Vietnam In the subsequent quantitative phase of the pilot study, face-to-face interviews with 100 team leaders were undertaken to refine the scales Cronbach’s alpha reliability and exploratory factor analysis (EFA) were used for preliminary assessment of the scales The main survey was also undertaken by using face-to-face interviews A sample of 302 team leaders working in the retail service industry in Ho Chi Minh City and Hanoi were interviewed to validate the measures and to test the structural model and hypotheses Confirmatory factor analysis (CFA) was utilized to assess the measures and structural equation modeling (SEM) was employed to test the theoretical model and hypotheses.

Study 1 examined key constructs such as ambidextrous leadership, which encompasses both opening and closing leadership behaviors, along with team exploratory and exploitative learning, and team innovative performance as assessed by team leaders These constructs were categorized as first-order constructs, with team innovation evaluated using three items from Welbourne et al (1998) on a 7-point scale from 1 (needs much improvement) to 7 (excellent) Additionally, opening leadership behavior was measured using three items, while closing leadership behavior was assessed through six adapted items.

Rosing et al (2011) utilized a 7-point scale to measure various items, ranging from 1 (not at all) to 7 (frequently) Team exploratory and exploitative learning were assessed using four items each, employing a 7-point Likert scale from 1 (strongly disagree) to 7 (strongly agree), as adapted from Kostopoulos and Bozionelos (2011) The initial questionnaire was developed in English and subsequently translated into Vietnamese by a bilingual academic, addressing the limited English proficiency among team leaders in Vietnam To ensure the accuracy of both versions, back translation was performed to resolve any discrepancies.

Previous studies indicate that team innovation can be influenced by factors such as the gender of team leaders, team size, and team tenure To address this, Study 1 accounts for these characteristics by implementing controls The gender of team leaders was coded using a dummy variable (1 for male, 0 for female), while team size was quantified by the number of employees in each team, and team tenure was assessed in terms of months of operation.

The measures were refined through Cronbach’s alpha reliability and exploratory factor analysis (EFA) conducted with data from 100 team leaders in a pilot study EFA, utilizing principal components with promax rotation, identified five factors explaining 70.48% of the variance, with an eigenvalue of 1.03 The Cronbach’s alpha values for the scales were 0.91 for opening leadership behavior, 0.85 for closing leadership behavior, 0.82 for team exploratory learning, 0.84 for team exploitative learning, and 0.84 for team innovation, with all factor loadings being significant (≥ 0.50) These findings confirmed that all scales met the reliability requirements, leading to their application in the main survey.

Through the screening process, 6 questionnaires were removed because they contained more than 10% of missing values Consequently the final sample size was

The study analyzed 296 team leaders, revealing a gender distribution of 182 (61.49%) females and 114 (38.51%) males Geographically, 198 (66.89%) operated in Ho Chi Minh City, while 98 (33.11%) were based in Hanoi Age-wise, a significant majority, 213 (71.96%), were under 30 years old, and 83 (28.04%) were over 30 In terms of education, 271 (91.55%) held an undergraduate degree, 10 (3.38%) had a postgraduate degree, and 15 (5.07%) had only a high school education Regarding team size, 150 (50.68%) teams had nine or fewer employees, while 146 (49.32%) had more than nine In terms of team tenure, 149 (50.34%) teams had been operational for over 18 months, compared to 147 (49.66%) with 17 months or fewer The types of retail service stores included 107 (36.15%) convenience stores, 85 (28.72%) in food and beverages, 40 (13.51%) in electronics, and 64 (21.62%) in various sectors such as pharmacy, women's and children's apparel, fashion, and cosmetics.

Data analysis and results

The study examined five key constructs: opening leadership behavior, closing leadership behavior, team exploratory learning, team exploitative learning, and team innovation To ensure reliability, the measurement scales for these constructs were refined using Cronbach’s alpha and exploratory factor analysis (EFA) on a pilot study dataset of 100 participants Subsequently, confirmatory factor analysis (CFA) was conducted on a larger dataset of 296 participants from the main survey to validate these scales.

The saturated model, developed from the confirmatory factor analysis (CFA) of five first-order constructs—opening leadership behavior, closing leadership behavior, team exploratory learning, team exploitative learning, and team innovation—demonstrated a good fit to the data with χ²(157) = 292.17 (χ²/df = 1.69), GFI = 0.91, CFI = 0.95, and RMSEA = 0.05 High and significant factor loadings (≥ 0.65, p < 0.001) were observed for the items measuring these constructs, with composite reliability exceeding 0.79 Additionally, the average variance extracted for each construct was greater than 0.50, confirming convergent validity Discriminant validity was also supported, as the correlation between any pair of constructs remained below the square root of the average variance extracted for each construct pair, in accordance with Fornell & Larcker (1981) Detailed CFA loadings, composite reliability, and average variance extracted for all scales are presented in Tables 2 and 3.

Table 2 Means (M), standard deviations (SD), and standardized CFA loadings () of items of Study 1

As a team leader, I allow different ways of accomplishing a task 4.51 2.086 0.70

As a team leader, I encourage experimentation with different ideas 5.00 1.928 0.93

As a team leader, I give room for own ideas 5.39 1.869 0.74

As a team leader, I monitor and control goal attainment 6.37 1.030 0.80

As a team leader, I establish routines 6.30 1.036 0.66

As a team leader, I take corrective action 6.27 1.066 0.73

As a team leader, I control adherence to rules 6.35 1.024 0.71

As a team leader, I pay attention to uniform task accomplishment 6.39 0.907 0.78

As a team leader, I stick to plans 6.36 0.910 0.65

Team members were systematically searching for new possibilities 5.73 1.207 0.75 Team members offered new ideas and solutions to complicated problems 5.74 1.208 0.82

Team members experimented with new and creative ways for accomplishing work 5.66 1.281 0.82

Team members evaluated diverse options 5.71 1.153 0.81

In our team, we primarily performed routine activities 6.06 1.078 0.69 Our team implemented standardized methodologies and regular work practices 6.28 0.826 0.70

Team members improved and refined their existing knowledge and expertise 6.18 0.915 0.77

Team members mainly used their current knowledge and skills for performing their tasks 6.24 0.936 0.71

My team comes up with new ideas 5.46 1.178 0.75

My team finds improved ways to do things 5.92 0.995 0.77

My team creates better processes and routines 5.67 1.328 0.67

Table 3 Correlations between constructs of Study 1

Note: CR: composite reliability; AVE: average variance extracted; numbers on the diagonal are square roots of average variances extracted; *p < 0.05; **p < 0.001; NS : non-significant.

Study 1 used a survey data set collected from a single respondent (i.e., team leaders), which may raise the problem of common method biases To assess this problem, we followed a procedure proposed by Podsakoff et al (2003) We first conducted a CFA Harman’s single factor model test and then undertook an unmeasured latent variable test (i.e., to allow an unmeasured latent variable to load on all items in the trait model) The results of the Harman’s test showed that the CFA Harman’s single factor model yielded a very poor fit to the data (χ 2 (167) 1612.93, GFI = 0.60, CFI = 0.46, and RMSEA = 0.17), compared to the trait model (χ 2 (157) = 292.17, GFI = 0.91, CFI = 0.95, and RMSEA = 0.05) The results from the unmeasured latent variable test indicated that all item loadings on the unmeasured latent variable were not significant and that each item loading in the final CFA model with and without the unmeasured latent variable was nearly identical Thus, common method bias was not a pervasive problem in Study 1 (Podsakoff et al., 2003).

3.4.2 Structural results and hypothesis testing

3.4.2.1 Testing the proposed model against its rivals

Structural Equation Modeling (SEM) was employed to evaluate the theoretical model and hypotheses Following the approach of Bollen and Long (1993), Study 1 introduced two competing models: the first model posited that the interaction between opening and closing leadership behaviors does not influence team exploratory and exploitative learning, while the second model suggested a direct effect of this interaction on team innovation Previous research by Zacher and Rosing (2015) indicated that the interplay of these leadership behaviors could significantly affect team innovation To measure this interaction, one indicator was utilized based on Ping (1995), and summated indicators were calculated, representing the product of opening and closing leadership behaviors, as both were treated as unidimensional constructs (Gerbing & Anderson, 1988) To prevent multicollinearity, mean-deviated variables were implemented in the analysis (Cronbach, 1987).

In Study 1, a Chi-square difference test was utilized to evaluate the proposed model against competing models, as outlined by Anderson and Gerbing (1988) The findings from the Structural Equation Modeling (SEM) indicated that all three models, including the proposed model and two alternatives, demonstrated an acceptable fit to the data, with the proposed model showing χ²(240) = 426.013 and a χ²/df ratio of 1.775.

The analysis revealed that the proposed model demonstrated a superior fit to the data compared to the more restrictive model, with a chi-square difference of Δχ² = 10.44 The fit indices for the proposed model were χ²(242) = 436.45 (χ²/df = 1.804), GFI = 0.896, CFI = 0.934, and RMSEA = 0.051 In contrast, the more restrictive model showed χ²(242) = 436.45 (χ²/df = 1.804), GFI = 0.893, CFI = 0.931, and RMSEA = 0.052, while the less restrictive model had χ²(239) = 426.013 (χ²/df = 1.782), GFI = 0.896, CFI = 0.933, and RMSEA = 0.052.

The analysis indicated a significant preference for the proposed model over the more restrictive alternative, with a statistical difference (Δdf = 2; p < 0.01) The less restrictive model did not demonstrate a better fit compared to the proposed model (Δχ² ~ 0, Δdf = 1; p ~ 1.00), despite using an additional degree of freedom Furthermore, the interaction between open and closing leadership behaviors did not significantly impact team innovation (p > 0.99), reinforcing the selection of the proposed model It is important to note that team exploratory and exploitative learning may coexist rather than being mutually exclusive, as suggested by Kostopoulos & Bozionelos.

A significant correlation (0.46, p < 0.001) was found between the residuals of the models analyzed, indicating a potential relationship between the variables Additionally, the analysis revealed no improper solutions, as there were no Heywood cases, all error-term variances were significant, and all standardized residuals remained within the acceptable range of less than |2.58|.

The SEM analysis indicated that all paths in the proposed model were significant, confirming the validity of the hypotheses presented However, leader gender, team size, and team tenure did not significantly influence team innovation Detailed results, including unstandardized estimates, standard errors, standardized estimates, t-values, and p-values for the structural paths, are summarized in Table 4.

Table 4 SEM results of Study 1

H1 Opening leadership behavior  Team exploratory learning 0.11 0.040 0.18 2.76 0.006

H2 Closing leadership behavior  Team exploitative learning 0.33 0.072 0.37 4.62 0.000

Opening leadership behavior* Closing leadership behavior  Team exploratory learning 0.09 0.033 0.17 2.61 0.009

H4 Opening leadership behavior* Closing leadership behavior  Team exploitative learning 0.07 0.027 0.20 2.67 0.008

H5 Team exploratory learning  Team innovation 0.60 0.074 0.62 8.13 0.000 H6 Team exploitative learning  Team innovation 0.31 0.086 0.23 3.66 0.000

Note: B: unstandardized regression weight; SE: standard error; β: standardized regression weight; t: t-statistic; p: p-value.

The study confirmed a significant positive relationship between opening leadership behavior and team exploratory learning (p < 0.01), supporting hypothesis H1 Additionally, hypothesis H2 was validated with a strong positive link between closing leadership behavior and team exploitative learning (p < 0.001) The interaction of opening and closing leadership behaviors positively influenced both team exploratory (H3) and exploitative learning (H4), with significant results (p < 0.01) Notably, team exploratory learning peaked when both leadership behaviors were high, while team exploitative learning also reached its highest levels under the same conditions Furthermore, a positive and significant relationship was established between team exploratory learning and team innovation (p < 0.001), affirming hypothesis H5, and hypothesis H6 was similarly supported, indicating that team exploitative learning positively affects team innovation (p < 0.001).

Figure 3 Interaction effect between opening and closing leadership behaviors on team exploratory learning

T ea m e xp lo ra to ry le ar n in g

Figure 4 Interaction effect between opening and closing leadership behaviors on team exploitative learning

Low closing leadership behavior High closing leadership behavior

T ea m e xp lo it at iv e le ar n in g

Discussion and implications

Study 1, grounded in ambidexterity theory, examined how team leaders' opening and closing leadership behaviors influence team exploratory and exploitative learning, ultimately impacting team innovation Survey data from 296 retail service team leaders in Vietnam revealed that opening leadership behavior enhances team exploratory learning, while closing leadership behavior supports team exploitative learning Additionally, the interaction between these leadership behaviors positively correlates with both types of team learning Ultimately, the study concludes that these learning processes significantly foster team innovation, providing valuable insights for theory, research, and practical applications.

The results of Study 1 significantly advance the understanding of ambidextrous leadership and its impact on team innovation Previous studies predominantly concentrated on organizational and individual levels, particularly within advanced economies, highlighting a gap in the literature that this research addresses.

A study conducted in Vietnam highlights the importance of ambidextrous leadership in enhancing team learning and innovation within retail services It reveals that leaders who exhibit opening behaviors foster exploratory learning, while those who display closing behaviors support exploitative learning This dual approach not only promotes learning activities among team members but also significantly contributes to team innovation, underscoring the critical role of leadership styles in a transitioning economy.

Study 1 explores the interaction between opening and closing leadership behaviors and their impact on team exploratory and exploitative learning In line with ambidextrous leadership theory, it reveals that both types of leadership behaviors yield the highest levels of learning when employed together This supports the call for further research into the dynamics of team learning Notably, the study also uncovers a direct interaction effect between these leadership behaviors and team innovation; however, it found no significant relationship when compared to a competing model, contradicting previous research by Zacher and Rosing, which identified a significant interaction effect This discrepancy suggests the potential presence of mediators, such as team exploratory and exploitative learning, that warrant further investigation.

Research indicates that both exploratory and exploitative learning significantly enhance team innovation, supporting the notion that these learning activities are distinct yet complementary Therefore, teams should engage in both types of learning to foster innovation effectively.

Team exploratory and exploitative learning play crucial roles in enhancing team performance, as demonstrated by Kostopoulos and Bozionelos (2011) Study 1's findings support the relevance of ambidextrous leadership theory for fostering innovation in transitioning economies, such as Vietnam.

Study 1 highlights the crucial role of training team leaders to enhance both opening and closing leadership behaviors, which are essential for fostering exploratory and exploitative learning within teams Organizational trainers should emphasize the significance of allowing errors, encouraging individual ideas, and promoting experimentation to create an environment conducive to exploratory learning Simultaneously, they should underscore the importance of monitoring progress, establishing routines, and adhering to plans to facilitate exploitative learning The ability to adeptly transition between these leadership styles can significantly boost team innovation by enhancing both exploratory and exploitative learning activities.

Study 1 has notable limitations, primarily its cross-sectional design, which hinders causal interpretations Future research should explore how ambidextrous leadership influences team exploratory and exploitative learning, impacting long-term team outcomes Additionally, the focus on retail service teams raises questions about the applicability of findings to other team types, such as pipeline operation teams, where strict regulations may discourage risk-taking Comparative studies between service teams and other team types are warranted Furthermore, factors like team psychological capital, psychological safety, and psychological contract breach could mediate or moderate the relationship between ambidextrous leadership and team innovation, highlighting the need for further investigation Lastly, the study's findings, derived from a Vietnamese context, may not be universally applicable.

This study lays the groundwork for future research to replicate and assess transitioning markets like China, enhancing our understanding of the innovation processes within teams Despite its limitations, Study 1 highlights the significant impact of opening and closing leadership behaviors on team exploratory and exploitative learning These leadership styles foster an environment where team members are motivated to generate and implement innovative ideas, particularly in the evolving landscape of retail services in a transitioning economy.

Inclusive leadership encompasses positive behaviors such as openness, accessibility, and a sense of belonging, fostering unique interactions with team members Research shows that inclusive leadership significantly improves various job outcomes, including proactive behaviors among employees.

2020), voice behavior (Guo et al., 2020), prosocial rule breaking (Wang & Shi,

Research has highlighted the significance of inclusive leadership in fostering creativity and innovation across various organizational levels, including individual, team, and organizational contexts (Choi et al., 2017; Gong et al., 2021; Javed et al., 2018; Javed et al., 2019; Siyal et al., 2021; Ye et al., 2019) However, there is a notable lack of studies focusing specifically on the impact of inclusive leadership on team-level innovation (Van Knippenberg & Van Ginkel, 2021) Several investigations have explored mediators and moderators in this relationship; for instance, Ye et al (2019) identified team voice as a mediator and performance pressure as a moderator affecting team innovation, while Leroy et al (2021) examined team-derived inclusion's mediating role in the link between inclusive leadership and team creativity Additionally, Ashikali et al (2020) analyzed how inclusive leadership moderates the relationship between team ethnic-cultural diversity and an inclusive climate Despite the importance of shared team psychological contract fulfillment and team proactive personality in influencing team outcomes (Chiu et al., 2016; Gibbard et al., 2017; Laulié & Tekleab, 2016), further research is needed to understand their roles fully.

INCLUSIVE LEADERSHIP AND INNOVATION: THE ROLE OF

Introduction

Inclusive leadership embodies positive behaviors that promote openness, accessibility, and a sense of belonging among team members This leadership style fosters unique interactions with followers, ultimately enhancing job outcomes like proactive engagement and initiative-taking By prioritizing inclusivity, leaders can significantly impact team dynamics and overall performance.

2020), voice behavior (Guo et al., 2020), prosocial rule breaking (Wang & Shi,

Research has explored the impact of inclusive leadership on creativity and innovation across organizational, team, and individual levels (Choi et al., 2017; Gong et al., 2021; Javed et al., 2018; Javed et al., 2019; Siyal et al., 2021; Ye et al., 2019) However, the connection between inclusive leadership and team-level innovation remains underexplored (Van Knippenberg & Van Ginkel, 2021) Several studies have identified mediators and moderators in this relationship; for instance, Ye et al (2019) highlighted the mediating effect of team voice and the moderating influence of performance pressure on team innovation Additionally, Leroy et al (2021) examined how team-derived inclusion mediates the relationship between inclusive leadership and team creativity, while Ashikali et al (2020) focused on the moderating role of inclusive leadership concerning team ethnic-cultural diversity and inclusive climate Despite the recognized importance of shared team psychological contract fulfillment and team proactive personality in team outcomes (Chiu et al., 2016; Gibbard et al., 2017; Laulié & Tekleab, 2016), their specific roles in the context of inclusive leadership and team innovation are still unclear.

This study extends social exchange theory (SET) to the team level, examining how shared team psychological contract fulfillment mediates the link between inclusive leadership and team innovation, while team proactive personality moderates the relationship between inclusive leadership and shared team psychological contract fulfillment Based on survey data from 300 team leaders in Vietnam's retail services, the findings confirm these relationships and identify shared team psychological contract fulfillment and team proactive personality as new facilitators of team innovation This research provides empirical evidence for SET in explaining team innovation within the context of Vietnam's transitioning economy.

Theoretical background and hypotheses

Social Exchange Theory (SET) posits that establishing exchange relationships benefits individuals and groups (Befu, 1977; Blau, 1964; Emerson, 1976) These relationships involve the reciprocal exchange of resources, where one party (A) provides resources to another (B), with the expectation of receiving something in return (Befu, 1977) At the individual level, SET suggests that people engage in exchanges to maximize rewards while minimizing costs (Cropanzano & Mitchell, 2005) The principle of reciprocity indicates that those who receive resources are obliged to return the favor (Gouldner, 1960) In a business context, psychological contracts reflect the reciprocal obligations between employees and employers (Rousseau, 1990) Key evaluations of psychological contracts include fulfillment, breach, and violation (Kutaula, Gillani, & Budhwar, 2020) Research has demonstrated that positive psychological contracts correlate with higher employee commitment, job satisfaction, organizational citizenship behavior, and performance (Birtch et al., 2016; Conway & Coyle-Shapiro, 2012; Kiazad et al., 2019; Solinger et al., 2016; Turnley et al., 2003), while negative associations exist with employee turnover intentions and counterproductive behaviors (Griep & Vantilborgh, 2018; Kraak et al., 2017).

The Social Exchange Theory (SET) posits that frequent social interactions and information sharing among employees can foster shared perceptions within teams, such as the psychological contract This shared understanding can influence the reciprocity between teams and organizations, contingent on the fulfillment of promised resources While an individual psychological contract refers to the personal exchange belief between an employee and their employer, a team psychological contract emerges from the collective perceptions formed through interactions among team members Previous studies have highlighted the significance of psychological contracts in various team outcomes, including team output, performance, organizational citizenship behaviors, and overall team contributions.

In the SET, leaders could play as a source of resources that their team members can refer to fulfill their team needs (Bordia et al., 2017; Nielsen et al.,

Inclusive leadership fosters high-quality relationships between leaders and followers by providing essential resources and enhancing relational support, thereby shaping a positive team climate (Carmeli, Reiter-Palmon, & Ziv, 2010) Nishii and Mayer (2009) emphasize that when leaders demonstrate acceptance of diverse employees, they can establish norms of equality and inclusion, promoting power sharing and improving reciprocal exchanges among team members Recent studies have explored various mediators and moderators affecting the relationship between inclusive leadership and innovation outcomes at both individual and team levels, including factors such as person-job fit, psychological empowerment, leader-member exchange, psychological safety, psychological capital, team voice, and performance pressure.

Table 5.A brief summary of empirical studies on the relationship between inclusive leadership and innovation

Authors Antecedents Moderators Mediators Outcomes Theories/

None Person-job fit Innovative behavior and well-being

Individual 207 employees in 5 telecommunication companies in Vietnam

Inclusive leadership was positively related to employee well-being and innovative behavior Person-job fit mediated these above relationships.

Individual 150 supervisors and 150 employees working in textile industry in Pakistan

Leader member exchange was partially mediated the impact of inclusive leadership on innovative work behavior.

Individual 390 employees working in the information technology and cargo sectors within the United Kingdom and Canada

Psychological empowerment was partially mediated the impact of inclusive leadership on employee innovative work behavior.

Individual 180 supervisors and 180 employees working in textile industry in Pakistan

Psychological safety was partially mediated the impact of inclusive leadership on employee innovative work behavior.

Not mentioned Individual 351 employees working in

Psychological capital mediated the impact of inclusive leadership on

Authors Antecedents Moderators Mediators Outcomes Theories/

Team Sample 1: Fifty-five team leaders and 230 team members of 55 teams in 2 companies from 2 industries, medical device and banking, in China

Sample 2: Sixty-six team leaders and 406 team members of 66 R&D software development teams in 5 companies in China

Team voice partially mediated the impact of inclusive leadership on team innovation The interaction between inclusive leadership and performance pressure affected team voice and, subsequently, leading to team innovation.

The moderated mediation model illustrated in Figure 5 explores the connection between inclusive leadership and team innovation, highlighting shared team psychological contract fulfillment as a mediator and team proactive personality as a moderator Additionally, the model considers team leaders' gender, team size, and team tenure as control variables for comprehensive analysis.

Figure 5 Conceptual model of Study 2

4.2.2.1 Inclusive leadership and team innovation

Research has identified several key factors that influence team innovation, including team structure, composition, climate, processes, and leadership (Anderson et al., 2014) Among these, leadership stands out as a critical determinant, as effective leaders foster strong relationships with team members to promote innovation They achieve this by providing necessary resources, offering relational support, cultivating a positive team climate, and addressing the functional needs of the team.

(Carmeli, Reiter-Palmon, & Ziv, 2010; Choi et al., 2017; Randel et al., 2018; Lee et al., 2020).

Teamwork creates the opportunity to bring diverse expertise and perspectives from team members to achieve team innovation (Thayer, Petruzzelli, & McClurg,

To maximize the benefits of innovative ideas within diverse teams, team leaders must navigate challenges stemming from the varied backgrounds, tenures, knowledge, and skills of their members Successfully addressing these challenges requires leaders to fulfill two essential group needs: fostering a sense of belonging and recognizing the uniqueness of each team member.

Inclusive leaders foster a sense of belonging while respecting individuality, enhancing team members' psychological empowerment and work group identification (Randel et al., 2018) This support is crucial during the idea implementation phase, often marked by frustration and uncertainty, enabling team members to thrive and recover in their roles The Social Exchange Theory suggests that when teams recognize the benefits of resources provided by their leaders, they feel compelled to reciprocate through collective efforts to meet organizational goals (Laulié & Tekleab, 2016) Consequently, as teams perceive value in the resources from their inclusive leaders, they are more likely to engage in developing and executing diverse ideas to achieve workplace objectives.

H1 Inclusive leadership has a positive effect on team innovation.

4.2.2.2 The mediating role of shared team psychological contract fulfillment

The psychological contract within work teams significantly influences members' willingness to exceed their responsibilities, particularly when organizations honor their commitments to the teams (Laulié and Tekleab, 2016) This concept encompasses two key types of fulfillment: shared team psychological contract fulfillment and shared individual psychological contract fulfillment (Laulié).

Multiple social interactions and information sharing among team members can enhance shared perceptions of psychological contract fulfillment At the team level, this shared psychological contract fulfillment refers to the alignment of team members' views on how well the organization has met its obligations to the team.

Shared team psychological contract fulfillment significantly influences team innovation, as teams that experience high fulfillment are more motivated to achieve their goals and contribute to collective success (Laulié & Tekleab, 2016; Schreuder et al., 2019; Tekleab et al., 2020) According to Social Exchange Theory (SET), the reciprocity between teams and organizations is contingent on the fulfillment of promised resources, leading to greater contributions from teams when these promises are met (Laulié & Tekleab, 2016) Research by Schreuder et al (2019) indicates that fulfilled individual psychological contracts correlate positively with team performance and organizational citizenship behaviors Conversely, when teams perceive unmet promises from the organization, their contributions may diminish (Laulié & Tekleab, 2016).

& Tekleab, 2016) Following this logic, shared team psychological contract breach was negatively related to team output (Gibbard et al., 2017) Accordingly, shared team psychological contract fulfillment is associated with team innovation.

Leadership styles play a crucial role in fostering shared psychological contract fulfillment within teams Inclusive leaders significantly shape their team members' perceptions of workplace tasks and goals By addressing two fundamental human needs, these leaders are more inclined to engage in discussions about expectations regarding resource exchanges, thereby fulfilling individual needs as part of their commitments.

Inclusive leaders foster improved communication within teams, enabling members to share their perceptions of how well promises related to team functions and operations are being fulfilled By encouraging team members to express themselves and feel like integral parts of the group, inclusive leaders empower individuals to contribute their unique skills and perspectives, ultimately enhancing the overall effectiveness of the team (Randel et al.).

Inclusive leaders enhance team members' shared perceptions regarding the fulfillment of organizational commitments, leading to a positive relationship between inclusive leadership and the fulfillment of the shared psychological contract within the team.

H2 Shared team psychological contract fulfillment positively mediates the relationship between inclusive leadership and team innovation.

4.2.2.3 The moderating role of team proactive personality

A proactive personality is defined as a personal disposition that drives individuals to recognize and seize opportunities, take initiative, and persist in creating meaningful change (Crant & Bateman, 2000) Research indicates that individuals with a proactive personality tend to experience higher levels of job satisfaction, creativity, leader-member exchange, and overall job performance (Kim, Hon).

Proactive personality at the team level is defined as the consensus among team members regarding their collective perception of proactive traits within the group This shared understanding influences team dynamics and effectiveness.

Research methods

Study 2 conducted a survey targeting retail service stores in two metropolitan cities of Vietnam, HCM City and Hanoi, to test the model and hypotheses Survey respondents were carefully chosen with at least 6 months’ experience as team leaders in the current position (i.e., the use of key informants suggesting by Kumar, Stern, and Anderson, 1993) To ensure the appropriateness of the contents of the measures to the retail service context in Vietnam, Study 2 also conducted three in- depth interviews with experienced store leaders working in both local and foreigner companies in HCM city to evaluate and examine how real respondents may described existing inclusive leadership, team proactive personality, shared team psychological contract fulfillment, and team innovation Further, the questionnaire was initially prepared in English and then translated into Vietnamese by an academic fluent in both languages This procedure was carefully undertaken because English is not well understood by all team leaders in Vietnam Back translation was followed to ensure that English and Vietnamese versions were comparable and any discrepancies were resolved Note that the questionnaire was designed based on scale items modified to measure at the team level so that we need to assess their understandability, clarity, and relevance in the retail service store context Some sample items in the questionnaire were “As a team leader, I support individuals as group members”, “The opportunities that my team members have to grow and advance”, “Wherever my team members have been, they have been a powerful force for constructive change”, and “My team members come up with new ideas” to measure inclusive leadership, shared team psychological contract fulfillment, team proactive personality, and team innovation, respectively Through these in-depth interviews, experienced store leaders contributed by ensuring the wording and meaning of the modified items in the retail service store market in Vietnam.

Between October 24, 2019, and January 1, 2020, a total of 300 team leaders completed questionnaires, with no responses discarded during the screening process The final sample consisted of 195 female team leaders (65.00%) and 105 male team leaders (35.00%).

The study involved 300 participants, evenly split between HCM City and Hanoi, with a significant majority (73.33%) under the age of 30 Educationally, 84% of team leaders held an undergraduate degree, while 8.33% had only a high school education, and 7.67% possessed a postgraduate degree Team sizes varied, with 53.67% consisting of eight or fewer employees, and 46.33% having more than eight In terms of operational tenure, 52.67% of teams had been functioning for 18 months or more, while 47.33% had less than 18 months of experience The types of retail service stores included 32% convenience stores, 27.33% in food and beverages, 10.67% in electronics, and the remaining 30% covering fashion, pharmacy, and cosmetics.

Study 2 examined four key constructs: inclusive leadership, shared team psychological contract fulfillment, team proactive personality, and team innovation Inclusive leadership, a second-order construct, consists of five components: openness, accessibility, availability, belongingness, and uniqueness, measured using twelve items on a seven-point scale Shared team psychological contract fulfillment, also a second-order construct, includes transactional, training, and relational obligations, assessed through eleven items on a seven-point scale Team proactive personality, a first-order construct, was evaluated using five items adapted for team context, employing a seven-point Likert scale Lastly, team innovation, another first-order construct, was measured with four items on a seven-point scale, utilizing a referent-shift approach for both shared team psychological contract fulfillment and team proactive personality.

1 (needs much improvement) to 7 (excellent), modified from Welbourne, Johnson, and Erez (1998) for use with the team.

Study 2 controls these team characteristics (i.e., the gender of team leaders,team size, and team tenure) which may be sources to predict team innovation(Hülsheger et al., 2009) The gender of team leaders refers to dummy coding (1:male; 0: female) Team size refers to the number of employees in a team Team tenure refers to the number of months in operation.

Data analysis and results

This study employed confirmatory factor analysis (CFA) to evaluate the measurement of four key constructs: inclusive leadership, shared team psychological contract fulfillment, team proactive personality, and team innovation Initially, CFA was conducted to validate the measures for inclusive leadership and shared team psychological contract fulfillment, which are identified as second-order constructs Subsequently, the CFA models for the two first-order constructs were analyzed to ensure their validity.

(team proactive personality and team innovation) were incorporated into the CFA model of inclusive leadership and shared team psychological contract fulfillment to form a saturated model (final measurement model).

The Confirmatory Factor Analysis (CFA) model for inclusive leadership demonstrated a satisfactory fit to the data, with χ² (47) = 89.65, GFI = 0.95, CFI = 0.97, and RMSEA = 0.06 All item factor loadings were significant (p < 0.001) and exceeded 0.50 The composite reliability (CR) and average variance extracted (AVE) for inclusive leadership components were as follows: belongingness (CR = 0.67, AVE = 0.52), availability (CR = 0.73, AVE = 0.48), accessibility (CR = 0.80, AVE = 0.67), opening (CR = 0.80, AVE = 0.57), and uniqueness (CR = 0.63, AVE = 0.46) Similarly, the CFA model for shared team psychological contract fulfillment also showed an acceptable fit, with χ² (41) = 90.81, GFI = 0.95, CFI = 0.97, and RMSEA = 0.06, where all item factor loadings were significant (p < 0.001) and greater than 0.70 The CR and AVE for shared team psychological contract components included transactional obligation (CR = 0.82, AVE = 0.61), training obligation (CR = 0.90, AVE = 0.69), and relational obligation (CR = 0.87, AVE = 0.63) The saturated model also fit the data well, with χ² (108) = 251.17, GFI = 0.90, CFI = 0.93, and RMSEA = 0.07, maintaining high and significant factor loadings (p < 0.001) Two composite measures were created by averaging items from both inclusive leadership and shared team psychological contract fulfillment for the saturated model.

The composite reliability and average variance extracted for team proactive personality (CR = 0.82, AVE = 0.47) and team innovation (CR = 0.86, AVE = 0.61) were found to be satisfactory Additionally, the correlation between any two constructs remained below the square root of the average variance extracted for each construct, which supports the discriminant validity of inclusive leadership, shared team psychological contract fulfillment, team proactive personality, and team innovation, as outlined by Fornell and Larcker (1981).

Study 2 used a survey data set collected from a single respondent (i.e., team leaders), which may raise the problem of common method bias To lessen this problem, in the design phase, Study 2 employed different scaling methods (i.e., Likert and rating scales) In this analysis phase, a CFA Harman’s single factor model test was undertaken The Harman’s test demonstrated that the model yielded a very poor fit to the data [ 2 = 1,103.71, df = 119 ( 2 /df = 9.28), GFI = 0.61, CFI 0.53, and RMSEA = 0.17], compared to the trait (saturated) model Accordingly, common method bias, if existed, was not a pervasive problem in this study (Podsakoff et al., 2003) Table 6 presents key constructs’ and items’ statistics and Table 7 displays the correlations among constructs together with their square roots of AVEs.

Table 6 Means (M), standard deviations (SD), and standardized CFA loadings () of items of Study 2

Inclusive leadership: Accessibility: Composite reliability (CR) = 0.80; Average variance extracted (AVE)

As a team leader, I encourage my team members to access me on emerging issues 6.17 0.902 0.72

As a team leader, I am accessible for discussing emerging problems 6.10 0.989 0.91

Inclusive leadership: Availability: CR = 0.73; AVE = 0.48

As a team leader, I am available for consultation on problems 6.17 0.968 0.74

As a team leader, I am an ongoing "presence" in my team 6.45 0.834 0.74

As a team leader, I am available for professional questions from my team members 6.15 1.002 0.57

Inclusive leadership: Belongingness: CR = 0.67; AVE = 0.52

As a team leader, I support individuals as group members 6.30 1.071 0.50

As a team leader, I ensure justice and equity 6.35 0.865 0.88

Inclusive leadership: Openness: CR = 0.80; AVE = 0.57

As a team leader, I am open to hearing new ideas 6.15 0.951 0.76

As a team leader, I am attentive to new opportunities to improve work processes 6.07 0.977 0.74

As a team leader, I open to discuss the desired goals and new ways to achieve them 6.04 1.051 0.76

Inclusive leadership: Uniqueness: CR = 0.63; AVE = 0.46

As a team leader, I encourage diverse contributions 5.96 0.961 0.72

As a team leader, I help group members fully contribute 5.98 0.928 0.63

Shared team psychological contract fulfillment: Transactional obligation: CR = 0.82; AVE = 0.61

A competitive salary for my team (a salary comparable to that paid by similar organizations) 5.06 1.256 0.73

A fair salary for my team (a salary that is reasonable for the jobs my team do) 5.28 1.179 0.89

Pay tied to the level of my team performance 5.35 1.168 0.70

Shared team psychological contract fulfillment: Training obligation: CR = 0.90; AVE = 0.69

My team members have significant opportunities for growth and advancement, with a strong emphasis on career development and promotions The average ratings reflect a positive outlook, with scores of 5.48 for growth opportunities, 5.46 for career development, and 5.50 for promotion potential, indicating a supportive environment for professional progress.

The career guidance and mentoring opportunities my team members receive 5.30 1.195 0.77

Shared team psychological contract fulfillment: Relational obligation: CR = 0.87; AVE = 0.63

The amount of job security my team members have 5.64 1.064 0.73

The extent to which my team members are treated with respect and courtesy 5.92 0.959 0.83

The quality of working conditions for my team 5.83 0.983 0.83

The extent to which my team members are treated fairly 5.85 0.993 0.79

Team proactive personality: CR = 0.82; AVE = 0.47

Wherever my team members have been, they have been a powerful force for constructive change 5.50 1.166 0.68

Nothing is more exciting than seeing ideas of my team members turn into reality 5.47 1.186 0.58

My team members excel at identifying opportunities 4.82 1.318 0.76

My team members are always looking for better ways to do things 5.19 1.241 0.72

My team members can spot a good opportunity long before others can 4.82 1.332 0.68

My team members come up with new ideas 4.82 1.375 0.76

My team members work to implement new ideas 5.01 1.347 0.83

My team members find improved ways to do things 5.46 1.219 0.80

My team members create better processes and routines 5.19 1.388 0.73

Table 7 Correlations between constructs of Study 2

1 Shared team psychological contract fulfillment 0.77 0.53 0.73

Note: Numbers on the diagonal are square roots of average variances extracted; all correlations are significant at p < 001.

4.4.3 Structural results and hypothesis testing

This study utilized structural equation modeling (SEM) to examine the theoretical model and hypotheses regarding the mediating role of shared team psychological contract fulfillment in the relationship between inclusive leadership and team innovation The bias-corrected bootstrap method was employed to ensure accurate confidence intervals Two models were analyzed: Model M0, which included shared team psychological contract fulfillment as a mediator and three control variables, tested the direct effects of inclusive leadership on team innovation, as well as the indirect effects of the mediator Model M1 further explored the mediation of shared team psychological contract fulfillment and the moderation of team proactive personality Importantly, no improper solutions, such as Heywood cases, were identified in any of the models.

The results produced by SEM revealed that Model M0 received an acceptable fit to the data: χ 2 (86) = 158.34 (χ 2 /df = 1.84), GFI = 0.93, CFI = 0.95, and RMSEA

The study found that inclusive leadership did not significantly impact team innovation (βstandardized = 0.15, p > 0.05), thus not supporting hypothesis H1 However, the bias-corrected bootstrap analysis with 1000 samples indicated a positive and significant indirect effect of inclusive leadership on team innovation through shared team psychological contract fulfillment (βstandardized = 0.16, p < 0.01, 95% CI [0.07, 0.29]) Additionally, factors such as team leaders’ gender, team size, and team tenure showed no significant effect on team innovation (βgender = -0.02, βsize = -0.08, βtenure = -0.05, p > 0.05).

The SEM analysis indicated that the model incorporating shared team psychological contract fulfillment as a mediator (M1) exhibited a satisfactory fit to the data, with χ² (176) = 339.87, GFI = 0.90, CFI = 0.92, and RMSEA = 0.06 Significant paths were found from inclusive leadership to shared team psychological contract fulfillment and from this fulfillment to team innovation (p < 0.001) Additionally, the bias-corrected bootstrap method with 1000 samples revealed a positive and significant indirect effect of inclusive leadership on team innovation through shared team psychological contract fulfillment (βstandardized = 0.08, p < 0.01; 95% CI [0.08, 0.33]), confirming H2 Furthermore, the interaction between team proactive personality and inclusive leadership significantly influenced shared team psychological contract fulfillment (βstandardized = 0.20, p < 0.01), supporting H3.

Table 8 SEM results of Study 2

Model M0 (overall model): Testing H1 and control variables

Direct effect: Inclusive leadership  Shared team psychological contract fulfillment 0.65 0.095 0.51 0.000

Direct effect: Shared team psychological contract fulfillment  Team innovation 0.49 0.127 0.32 0.000

Indirect effect: Inclusive leadership  Shared team psychological contract fulfillment  Team innovation BC 0.32 0.120 0.16 0.001

Leader gender (male)  Team innovation -0.04 0.130 -0.02 0.738

Model M1: Shared team psychological contract fulfillment was the mediator: Testing H2, H3

Direct effect: Inclusive leadership  Shared team psychological contract fulfillment 0.54 0.100 0.45 0.000

Direct effect: Shared team psychological contract fulfillment

Indirect effect: Inclusive leadership  Shared team psychological contract fulfillment  Team innovation BC 0.33 0.139 0.17 0.001

H3 Inclusive leadership*Team proactive personality  Shared team psychological contract fulfillment 0.05 0.015 0.20 0.001

Note: B: unstandardized regression weight; SE: standard error; β: standardized regression weight; p: p-value; BC : bias-corrected bootstrap estimate.

Discussion and implications

Study 2 explored the connection between inclusive leadership and team innovation, emphasizing the mediating role of shared team psychological contract fulfillment Analyzing survey data from 300 team leaders in Vietnam's retail services, the findings revealed that inclusive leadership behavior alone did not influence team innovation However, shared team psychological contract fulfillment was found to mediate the relationship between inclusive leadership and team innovation Notably, the interaction between team proactive personality and inclusive leadership behavior positively correlated with shared team psychological contract fulfillment These insights provide valuable implications for both theoretical research and practical applications.

Recent findings underscore the significant impact of inclusive leadership on team dynamics, particularly in enhancing shared team psychological contract fulfillment and fostering innovation This aligns with earlier research by Ye et al (2019), which established a positive correlation between inclusive leadership and team innovation, albeit with the inclusion of team voice as a mediator The observed positive influence of inclusive leadership on fulfilling shared psychological contracts emphasizes the crucial role of team leaders in shaping the psychological attributes of their teams, highlighting the necessity of inclusive leadership for strengthening team cohesion and performance.

Team leaders who exhibit strong inclusive leadership behaviors are more inclined to foster a shared psychological contract within their teams, which subsequently enhances team innovation Previous studies suggest that certain leadership styles, such as transformational and servant leadership, are linked to the fulfillment of this shared psychological contract, ultimately driving improved team performance (Laulié & Tekleab, 2016).

In addition, Study 2 addresses the calls to test the two new components of inclusive leadership (i.e., belongingness and uniqueness) suggested by Randel et al.

In 2018, Study 2 explored an enhanced model of inclusive leadership characterized by five key components: openness, accessibility, availability, belongingness, and uniqueness This research deepens our understanding of inclusive leadership and its elements, indicating their potential to foster positive outcomes (Randel et al., 2018).

Research indicates that shared team psychological contract fulfillment is a crucial factor in driving innovation within teams To foster innovation, it is essential for teams to cultivate this shared fulfillment However, this conclusion contrasts with earlier studies, such as Gibbard et al (2017), which suggested that person-team fit mediates the link between psychological contract breaches and team performance These discrepancies highlight the potential presence of mediating factors that could influence the relationship between shared team psychological contract fulfillment and team innovation.

Study 2 findings also highlight the moderating role that team proactive personality plays in explaining shared team psychological contract fulfillment. Team proactive personality can be a substitute source of resources for team leaders to influence the perceptions of their team members about the promised obligation fulfillment of organization, enabling them to strengthen the effect of inclusive leadership on shared team psychological contract fulfillment The role of team proactive personality has also been verified by past research in team outcomes and related areas For instance, Chiu, Owens, and Tesluk (2016) found that team proactive personality positively moderates the impact of leader humility and shared leadership Wang et al (2017) found that team proactive personality mean moderates the positive relationship between employee proactive personality and work engagement, while team proactive personality diversity does not The findings of Study 2 further confirm the explaining power of SET in teams in a transitioning market, Vietnam, encouraging further research on this specific leadership style – inclusive leadership – in such a market.

Fostering inclusive leadership is crucial for enhancing team outcomes, such as shared psychological contract fulfillment and innovation Our findings, aligned with Ye et al (2019), suggest that leadership training interventions can significantly improve inclusive leadership behaviors, addressing the needs and attitudes of team members Organizational trainers should emphasize the importance of providing resources, supporting relationships, and recognizing individual uniqueness within the group Additionally, fulfilling the psychological contract at the team level may yield greater benefits than focusing solely on individual contracts The impact of inclusive leadership on shared psychological contract fulfillment is further amplified by high team proactive personality, indicating that inclusive leaders can cultivate a supportive social environment that encourages positive relationships and drives team innovation.

Study 2 has notable limitations that future research should address Its cross-sectional design prevents causal interpretations, highlighting the need for studies that explore the impact of inclusive leadership on shared team psychological contract fulfillment and subsequent team outcomes over time Additionally, while this study concentrated on retail service teams, it opens avenues for confirming findings across various team types Other mediating or moderating factors, such as team positive psychological resources and work contexts, warrant investigation to fully understand the relationship between inclusive leadership and team innovation Furthermore, the research was conducted within the Vietnamese context, suggesting the necessity for studies in diverse settings to enhance generalizability Despite these limitations, Study 2 enriches our understanding of team innovation processes, particularly emphasizing the positive influence of inclusive leadership on fostering high-quality relationships that promote innovation within teams in the evolving retail service sector of a transitioning economy.

TEAM PSYCHOLOGICAL CAPITAL AND INNOVATION: THE

CONCLUSION