Exercise and Muscle Performance

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A STUDY OF THE RELATIONSHIP BETWEEN CEO COMPENSATION AND FIRM PERFORMANCE IN THE U.S. AIRLINE INDUSTRY: 2002-2006 By Trudy Dawkins Morlino RICHARD MURPHY, D.B.A., Faculty Mentor and Chair THOMAS FORD, Ed.D., Committee Member KENNETH GRANBERRY, D.I.B.A., Committee Member Kurt Linberg, Ph.D., Dean, School of Business & Technology A Dissertation Presented in Partial Fulfillment Of the Requirements for the Degree Doctor of Philosophy Capella University September 2008 3324731 3324731 2008 Copyright 2008 by All rights reserved © Trudy Morlino, 2008 Abstract This study addressed the relationship between CEO compensation and firm performance in the U.S. domestic passenger airline industry, a low managerial discretion industry. To answer the question, is there a relationship between CEO compensation (salary plus bonus) and the independent variables, return on assets, return on equity and the debt-to-asset ratio, this study applied nonparametric statistics to a sample of publicly traded U.S. airlines for a five-year period, 2002-2006. Data for the study period relied exclusively on secondary data compiled by the Securities and Exchange EDGAR database and publicly available annual reports. The sample for this study consisted of 15 years of CEO compensation and firm performance data for three of the historically dominant U.S. scheduled domestic passenger airlines, SIC 4512, NAICS 48111. This study was limited to publicly traded U.S. ‘legacy’ airlines that operated primarily as a scheduled air passenger service where the CEO of the firm held the position for three consecutive years during the study period. Tests were conducted using Pearson product moment correlation and Spearman’s rank correlation. However, for this study, all hypotheses were tested using Spearman’s correlation coefficient. Spearman’s rho (p) nonparametric statistic was chosen because three major assumptions of the Pearson’s parametric correlation (r) were violated. The results indicated that there is a statistically significant negative relationship between the rank ordered CEO compensation (salary plus bonus) and rank ordered return on assets (ROA). The study found no statistically significant relationship between rank ordered CEO compensation (salary plus bonus) and rank ordered return on equity (ROE) or between the rank ordered CEO compensation (salary plus bonus) and the rank ordered debt-to-asset ratio. iii Dedication This work is dedicated to my daughter, Rebecca, who gave me the courage to undertake this project. Without her love, understanding and support this work would not have been possible. Her encouragement, patience, and belief in me throughout this journey allowed me to reach my goal. I would also like to dedicate this work to my husband, Buster, my sister, Cassie, and my brother, Chuck, for their ability to offer constructive criticism when needed as well as for their financial support throughout this process. To my parents, Becky and Harold Dawkins, who are looking down on me from above, thank you for giving me the foundation I needed to even consider such an undertaking as this. iv Acknowledgements First and foremost, I am extremely grateful to my Exercise and Muscle Performance Exercise and Muscle Performance Bởi: OpenStaxCollege Physical training alters the appearance of skeletal muscles and can produce changes in muscle performance Conversely, a lack of use can result in decreased performance and muscle appearance Although muscle cells can change in size, new cells are not formed when muscles grow Instead, structural proteins are added to muscle fibers in a process called hypertrophy, so cell diameter increases The reverse, when structural proteins are lost and muscle mass decreases, is called atrophy Age-related muscle atrophy is called sarcopenia Cellular components of muscles can also undergo changes in response to changes in muscle use Endurance Exercise Slow fibers are predominantly used in endurance exercises that require little force but involve numerous repetitions The aerobic metabolism used by slow-twitch fibers allows them to maintain contractions over long periods Endurance training modifies these slow fibers to make them even more efficient by producing more mitochondria to enable more aerobic metabolism and more ATP production Endurance exercise can also increase the amount of myoglobin in a cell, as increased aerobic respiration increases the need for oxygen Myoglobin is found in the sarcoplasm and acts as an oxygen storage supply for the mitochondria The training can trigger the formation of more extensive capillary networks around the fiber, a process called angiogenesis, to supply oxygen and remove metabolic waste To allow these capillary networks to supply the deep portions of the muscle, muscle mass does not greatly increase in order to maintain a smaller area for the diffusion of nutrients and gases All of these cellular changes result in the ability to sustain low levels of muscle contractions for greater periods without fatiguing The proportion of SO muscle fibers in muscle determines the suitability of that muscle for endurance, and may benefit those participating in endurance activities Postural muscles have a large number of SO fibers and relatively few FO and FG fibers, to keep the back straight ([link]) Endurance athletes, like marathon-runners also would 1/7 Exercise and Muscle Performance benefit from a larger proportion of SO fibers, but it is unclear if the most-successful marathoners are those with naturally high numbers of SO fibers, or whether the most successful marathon runners develop high numbers of SO fibers with repetitive training Endurance training can result in overuse injuries such as stress fractures and joint and tendon inflammation Marathoners Long-distance runners have a large number of SO fibers and relatively few FO and FG fibers (credit: “Tseo2”/Wikimedia Commons) Resistance Exercise Resistance exercises, as opposed to endurance exercise, require large amounts of FG fibers to produce short, powerful movements that are not repeated over long periods The high rates of ATP hydrolysis and cross-bridge formation in FG fibers result in powerful muscle contractions Muscles used for power have a higher ratio of FG to SO/ FO fibers, and trained athletes possess even higher levels of FG fibers in their muscles Resistance exercise affects muscles by increasing the formation of myofibrils, thereby increasing the thickness of muscle fibers This added structure causes hypertrophy, or the enlargement of muscles, exemplified by the large skeletal muscles seen in body builders and other athletes ([link]) Because this muscular enlargement is achieved by the addition of structural proteins, athletes trying to build muscle mass often ingest large amounts of protein 2/7 Exercise and Muscle Performance Hypertrophy Body builders have a large number of FG fibers and relatively few FO and SO fibers (credit: Lin Mei/flickr) Except for the hypertrophy that follows an increase in the number of sarcomeres and myofibrils in a skeletal muscle, the cellular changes observed during endurance training not usually occur with resistance training There is usually no significant increase in mitochondria or capillary density However, resistance training does increase the development of connective tissue, which adds to the overall mass of the muscle and helps to contain muscles as they produce increasingly powerful contractions Tendons also become stronger to prevent tendon damage, as the force produced by muscles is transferred to tendons that attach the muscle to bone For effective strength training, the intensity of the exercise must continually be increased For instance, continued weight lifting without increasing the weight of the load does not increase muscle size To produce ever-greater results, the weights lifted must become increasingly heavier, making it more difficult for muscles to move the load The muscle then adapts to this heavier load, and an even heavier load must be used if even greater muscle mass is desired If done improperly, resistance training can lead to overuse injuries of the muscle, tendon, or bone These ... Measuring and Tuning Performance This chapter covers • Performance optimization • Caching • Balancing items in containers • Using API searches efficiently • Limiting the use of placeholders • Site navigation considerations • Capacity planning • Analysis and general considerations • Transactions • Failure of criteria • Building a test site Microsoft Content Management Server provides tools to plan, analyze, and test an MCMS Web site to optimize its performance and ensure that it can meet the required load. Optimal performance is achieved through opti- mization of caching, scaling, and tuning to eliminate throughput bottlenecks. Data provided in this section have been compiled from tests and analy- ses that Microsoft has performed using the Microsoft Web Application Stress Tool (WAST) and the Transaction Cost Analysis (TCA) tool from the Microsoft Commerce Server 2000 performance toolkit. WAST is a load-generation tool and TCA acts as a WAST controller. This chapter presents Microsoft’s recom- mendations for MCMS settings (primarily caching) that can be tuned to increase site performance and ameliorate known performance limitations. This chapter also covers site design considerations and capacity planning at a high level. CHAPTER 3 39 Performance Optimization Optimal performance is primarily based on the speed at which a page is served. Testing performance, therefore, requires projecting requests per second. Throughput is measured as • Pages per second: A page is what the user sees after making a request; one page can contain many data (ASP) requests that a server must exe- cute or redirect. • ASP requests per second: Each ASP request can contain many Get requests. • Gets per second: Individual requests for objects such as images. The number of concurrent users on the site also affects throughput. Two methods to maximize performance seem to yield useful results: • Tuning performance with configuration settings and fragment caching • Careful planning of site content at designtime, such as containers, searches, placeholders, and navigation Caching Microsoft recommends setting the system cache to a size large enough to hold the bulk of your binary data. Make sure the maximum number of nodes in the memory cache is sufficient to hold the most commonly accessed pages on your site. Keep in mind that a single page may require many nodes to be displayed, depending on such elements as navigation, page depth, and sib- lings. Performance of Web entry points marked as read-only can also improve 10% on average (MCMS uses less script code to serve a read-only request than read/write). Read-only and read/write entry points for the same site may require different-sized caches. Object retrieval directly from the Content Repository for every trans- action often presents a bottleneck. To improve response time, MCMS provides memory-object and file-system (disk) caches. The memory object cache stores data relating to API objects (channels, placeholders, and so on) and is queried when an object is requested. The file system cache stores binary data—resources, such as graphics and templates. Each page request requires rendering a number of COM objects (into HTML), and each time, the objects are created and destroyed. Fragment caching saves the output obtained from the first rendering into the cache. The fragment is output immediately and is stored in the cache for future use, with little overhead. Use fragment caching for guest access because it’s typi- cally the most frequent during high loads. Fragment caching should not be CHAPTER 3 ■ MEASURING AND TUNING PERFORMANCE40 used during site design because new objects are constantly being created, which causes the cache to The TrueNet® CopperTen® limited Warranty applies to a qualifying cabling system (“Certified System”) installed by a TrueNet® Value Added Reseller (VAR) in the United States, and appropriately registered with ADC as evi- denced by a numbered TrueNet®Certified System Reg- istration Certificate (“Registration Certificate”) issued by ADC to the end-user. All of the above are referred to as “Conditions” to the effectiveness of the Warranty. Warranty Coverage The TrueNet® CopperTen® 20-year Warranty includes parts and labor for all components and applications listed on the Schedule of Products and Applications at- tached to the Registration Certificate (the “Schedule”). Subject to the limitations contained herein, for a period of 20 years from the date that all conditions to the effec- tiveness of the Warranty have been met, ADC warrants to the end-user that: (1) All components listed on the Schedule will be free from defects in material or workmanship under nor- mal and proper use; (2) All components listed on the Schedule will meet or exceed the specifications of the ANSI/TIA/EIA 568-B and all addendum standards in effect on the date the Warranty becomes effective unless otherwise specifically noted on the Schedule of Products and Applications; (3) The Certified System will meet or exceed the Inser- tion Loss (IL) , Return Loss (RL) and Near-End Cross- talk (NEXT) requirements of ANSI/TIA/EIA 568-B, ISO/ IEC 11801 & ANSI/TIA/EIA TSB-67 for cabling chan- nels in effect on the date the Warranty becomes ef- fective; and (4) The Certified System will be free from defects that would prevent operation of the Applications listed on the Schedule (5) In addition, for a period of 20 years from the effec- tive date of the Warranty, a throughput “zero-bit error” Warranty shall be provided for each channel component of the CopperTen® Certified System that meet the conditions, including testing, with equipment that exceeds the most recent IEEE 802.3 specifications at that date in an operational envi- ronment without adverse environmental conditions (e.g., external noise sources). All testing shall be per- formed with hardware, software and test method- ologies approved in writing by ADC. Testing will be performed over a set period of time over a predeter- mined amount of nodes with the intent to verify that no errors are present during the testing period for the specific structured cabling node(s) under test. What ADC Will Do When a Certified System end-user believes, after reason- able investigation, that a failure in the operation of an Application listed on the Schedule is the result of the failure of the Certified System to meet its warranted specifications or performance, it shall promptly notify ADC in writing. ADC may require, at its sole discretion, payment of ADC’S then-current charge to the end-user to cover testing by ADC of the Certified System. As a re- sult of such testing and any additional review, ADC shall determine its responsibility and provide any appropriate remedies pursuant to this Warranty, including repayment of the testing charge. If the Certified System or any component thereof fails to meet the Warranty set forth above as determined by ADC, ADC will at its sole discretion either cause the defective component or components to be repaired, or provide a replacement product or active electronic com- ponents to achieve Warranty compliance, or refund to the end-user the purchase price of the defective com- ponents. If ADC elects to replace any components, it may use new or reconditioned replacement parts with the same or reasonably equivalent specifications. Any such repair or replacement shall be warranted under the terms of this Warranty for the remainder of the term of this DEMOCRACY AND ECONOMIC PERFORMANCE 1 Dani Rodrik Harvard University December 14, 1997 Does democracy hurt or help economic performance? There are few questions in political economy that have attracted more attention over the years. Thinking on this subject, in one form or another, goes all the way back to Plato—who favored aristocracy to democracy—and has preoccupied many of the most fertile minds in political philosophy. More recently, with the advent of cross-national data sources and statistical techniques, there have been numerous econometric studies investigating the relationship between political liberties and economic growth. 2 In policy circles, discussions on this issue inevitably gravitate toward the experience of a handful of economies in East and Southeast Asia, which (until recently at least) registered the world’s highest growth rates under authoritarian regimes. These countries constitute the chief exhibit for the argument that economic development requires a strong hand from above. The deep economic reforms needed to embark on self-sustaining growth, this line of thought goes, cannot be undertaken in the messy push and pull of democratic politics. Chile under Pinochet is usually exhibit no. 2. A systematic look at the evidence, however, yields a much more sanguine conclusion. While East Asian countries have prospered under authoritarianism, many more have seen their 1 Paper prepared for a conference on democratization and economic reform in South Africa, Cape Town, January 16-19, 1998. I am grateful to Sam Bowles for comments and Joanna Veltri for editorial suggestions. 2 See in particular Helliwell (1994) and Barro (1996, Lecture II). These two studies are also a good source for citations on the earlier literature. Przeworski and Limongi (1993) is a good introduction to the conceptual issues. 2 economies deteriorate—think of Zaire, Uganda, or Haiti. Recent empirical studies based on samples of more than 100 countries suggest that there is little reason to believe democracy is conducive to lower growth over long time spans. 3 Neither is it the case that economic reforms are typically associated with authoritarian regimes (Williamson 1994). Indeed, some of the most successful reforms of the 1980s and 1990s were implemented under newly-elected democratic governments—think of the stabilizations in Bolivia (1985), Argentina (1991), and Brazil (1994), for example, or of the Polish transition from socialism. Should we be agnostic then about the economic implications of democracy? Since civil liberties and political rights have intrinsic value independent of their economic consequences, it is good to know that fledgling democracies do not necessarily face any tradeoffs. But there is more to be said on behalf of democracy. As I will demonstrate in this paper, democracies perform better than authoritarian regimes in a number of respects which have received scant attention to date. I will show four results in particular: 1. Democracies yield long-run growth rates that are more predictable. 2. Democracies produce greater stability in economic performance. 3. Democracies handle adverse shocks much better. 3 Helliwell (1994) and Barro (1996) try to control for the endogeneity of democracy in estimating the effect of the latter on growth. Helliwell finds that democracy spurs education and investment, but has a negative (and insignificant) effect on growth when investment and education are controlled. On balance, he finds no “systematic net effects of democracy on subsequent economic growth.” Barro finds a non-linear relationship, with growth increasing in democracy at low levels of democracy and decreasing in democracy at higher levels. The turning point comes roughly Overview Series: Windows Vista® Performance and Tuning Improve Performance Quickly and Easily The Windows Vista® operating system and the recent Service Pack 1 (SP1) provide major advancements in usability, reliability, connectivity, and security. These improvements are helping businesses and consumers become more productive than ever. While performance is often thought of simply in terms of speed, it is better to think of performance as a combination of speed and responsiveness. For example, one approach to optimizing performance when copying large numbers of files would be to copy those files as fast as physically possible. Unfortunately, this approach would leave the system unresponsive during the operation. Windows Vista and SP1 focus on delivering greater performance and overall system responsiveness. By striking a balance between speed and responsiveness, Windows Vista and SP1 deliver a level of performance that has the greatest positive impact on the system’s usability. Improving the performance of a computer follows the principle of diminishing returns. There are a few actions you can take with any computer that should improve performance dramatically. Additional actions provide smaller performance improvements. This guide looks at the following areas of performance improvement:  Making configuration changes that help a computer feel more responsive when you use it.  Using hardware to boost the actual physical speed of a computer.  Making configuration changes that help a computer to start faster.  Making the computer more reliable may help increase performance.  Monitoring performance occasionally so that you can stop problems before they get too big. While the bulk of this guide focuses on performance improvements on a single computer, this guide also takes a look at some of the tools used in enterprise environments to help make performance tuning manageable on a much larger scale. Optimizing Hardware Specifications to Your Organizational Needs Although the minimum requirements for the Windows Vista operating system are highlighted in the Windows Vista TechCenter, you should validate hardware performance with your intended applications and user expectations before determining your organization’s standard hardware specifications. For example, when deploying Windows Vista many organizations have found that the following configuration yields good results, especially for higher knowledge worker scenarios:  At least 2 GB of RAM.  At least a 2 GHz processor.  A compatible graphics adapter that provides improved performance. If you are deploying Windows Vista with the Windows® Basic theme settings, you can reduce these recommendations considerably. Customize the hardware specifications and operating system configurations based on the user roles and operational needs in your organization. For more information about customizing the hardware specifications and operating system configuration, see:  Windows Vista Enterprise Hardware Planning Guidance http://technet.microsoft.com/en- us/windowsvista/aa905075.aspx Make Your Computer Feel More Responsive Another way to improve perceived performance on a computer is to make it feel faster. Or more accurately, you can remove things that make the computer feel slower. You do this by making sure that various configuration settings are optimized. Check Power Settings on Mobile Computers When a computer is operating on a battery, you must strike a balance between battery life and performance. Better performance almost always drains battery life more quickly. Windows Vista provides three built-in power plans, as ... fibers die, and they are replaced by connective tissue and adipose tissue 4/7 Exercise and Muscle Performance ([link]) Because those tissues cannot contract and generate force as muscle can, muscles... Overworking skeletal muscles can also lead to tendon damage and even skeletal damage if the load is too great for the muscles to bear 3/7 Exercise and Muscle Performance Performance-Enhancing... athletes use performance- enhancing substances to enhance muscle performance Muscle atrophy due to age is called sarcopenia and occurs as muscle fibers die and are replaced by connective and adipose