Correlation is significant at the 0.05 level 2-tailed.. The correlation between Joining Year and City is slightly positive, albeit weak, and is statistically significant with a significa
Trang 1NATIONAL ECONOMICS UNIVERSITY
Business School
BUSINESS STATISTICS Group Assignment
Group member : Tran Chau Giang – 11221833
Cao Tien Phuc – 11225128
Nguyen Cong Duy Khanh – 11223046
Tran Bao Quan- 11225409
Hanoi, July 5th 2023
Trang 2Case Study 1: Employee
1,
a, Do necessary data cleaning
Case Processing Summary
Cases
Age 1000 100,0% 0 0,0% 1000 100,0%
CT 1000 100,0% 0 0,0% 1000 100,0%
Trang 6After the coding process, the dataset is now clean Despite the presence of outliers in some variables as shown in the charts, the data can still be considered clear This clarity is attributed to the limited types of data representing the variables, which results in significantly high frequencies.
Trang 7Statistics
JoiningYea
r
PaymentTie
Gende r EverBenche d Experienc
LeaveOrNo
N Valid 1000 1000 1000 1000 1000 1000 1000 1000 1000
Missin
g
Mean 2015,1160 2,6930 26,494
0 ,62 ,10 3,1380 1,285
0 ,3560 1,780 0
Median 2015,0000 3,0000 26,000
0 1,00 ,00 3,0000 1,000
0 ,0000 2,000 0
Std
Deviation
1,84931 ,56309 2,5757
7 ,487 ,303 1,29408 ,5273
1 ,47905 ,8211 4
Minimum 2012,00 1,00 22,00 0 0 ,00 1,00 ,00 1,00
Maximum 2018,00 3,00 40,00 1 1 5,00 3,00 1,00 3,00
Descriptives
Statistic Std Error
95% Confidence Interval for Mean Lower Bound 2015,0012
Upper Bound 2015,2308
95% Confidence Interval for Mean Lower Bound 2,6581
Upper Bound 2,7279
Trang 8Range 2,00
95% Confidence Interval for Mean Lower Bound 26,3342
Upper Bound 26,6538
95% Confidence Interval for Mean Lower Bound ,59
95% Confidence Interval for Mean Lower Bound ,08
Trang 9Kurtosis 4,948 ,155
95% Confidence Interval for Mean Lower Bound 3,0577
Upper Bound 3,2183
95% Confidence Interval for Mean Lower Bound ,3263
Upper Bound ,3857
95% Confidence Interval for Mean Lower Bound 1,7290
Upper Bound 1,8310
Trang 10Upper Bound 1,3177
Percentiles
Percentiles
Weighted
Average(Definiti
on 1)
JoiningYear 2012,000
0 2013,000 0 2014,000 0 2015,000 0 2017,000 0 2017,000 0 2018,000 0
PaymentTie
r
1,0000 2,0000 2,0000 3,0000 3,0000 3,0000 3,0000
Age 24,0000 24,0000 25,0000 26,0000 27,0000 28,0000 30,0000
Experience 1,0000 2,0000 2,0000 3,0000 4,0000 5,0000 5,0000
EverBenche
d
,00 ,00 ,00 ,00 ,00 1,00 1,00
LeaveOrNot ,0000 ,0000 ,0000 ,0000 1,0000 1,0000 1,0000
Edu 1,0000 1,0000 1,0000 1,0000 1,0000 2,0000 2,0000
CT 1,0000 1,0000 1,0000 2,0000 3,0000 3,0000 3,0000
Tukey's Hinges JoiningYear 2014,000
0 2015,000 0 2017,000 0
PaymentTie
r
2,0000 3,0000 3,0000
Age 25,0000 26,0000 27,0000
Experience 2,0000 3,0000 4,0000
EverBenche
d
,00 ,00 ,00
Edu 1,0000 1,0000 1,0000
Trang 11Correlations
Trang 12Sig (2-tailed) ,024
Sum of Squares and Cross-products 3416,544 108,520
Sum of Squares and Cross-products 108,520 673,600
* Correlation is significant at the 0.05 level (2-tailed)
The correlation between Joining Year and City is slightly positive, albeit weak, and is statistically significant (with a significance level below 0.05) The Pearson Correlation coefficient lies between 0.1 and 0.3, indicating a modest but noticeable relationship between these two variables.
Correlations
PaymentTier Experience
Sum of Squares and Cross-products 316,751 -2,634
Sum of Squares and Cross-products -2,634 1672,956
There is no correlation between Payment Tier and Experience (Sig > 0.05)
Correlations
Sum of Squares and Cross-products 6627,964 -11,790
Sum of Squares and Cross-products -11,790 277,775
Trang 13There is no correlation between Age and Education (Sig > 0.05)
Correlations
PaymentTier Edu
Sum of Squares and Cross-products 316,751 -51,505
Sum of Squares and Cross-products -51,505 277,775
There is a weak negative relationship between Payment Tier and Education (Sig
< 0.05, 0.1<| Pearson Correlation |< 0.3)
Correlations
EverBenched PaymentTier
Sum of Squares and Cross-products 91,596 4,314
Sum of Squares and Cross-products 4,314 316,751
There is no correlation between Ever Benched and Payment Tier (Sig > 0.05)
d,
Descriptives
Statistic Std Error
95% Confidence Interval for Mean Lower Bound 2015,0012
Trang 14Median 2015,0000
95% Confidence Interval for Mean Lower Bound 2,6581
Upper Bound 2,7279
95% Confidence Interval for Mean Lower Bound 26,3342
Upper Bound 26,6538
95% Confidence Interval for Mean Lower Bound ,59
Trang 15Minimum 0
95% Confidence Interval for Mean Lower Bound ,08
95% Confidence Interval for Mean Lower Bound 3,0577
Upper Bound 3,2183
95% Confidence Interval for Mean Lower Bound ,3263
Upper Bound ,3857
Trang 16Interquartile Range 1,00
95% Confidence Interval for Mean Lower Bound 1,7290
Upper Bound 1,8310
95% Confidence Interval for Mean Lower Bound 1,2523
Upper Bound 1,3177
With the confidence level of 95%, the confidence interval is from the lower bound to the upper bound on the descriptive tables.
2, Based on the human resource management perspective, here are some revised recommendations for businesses:
Since there's a positive correlation between the number of years an employee has worked and their city of residence, it's evident that those living farther away may exert more effort commuting, potentially impacting their loyalty Companies should consider implementing support policies for transportation or travel expenses, thereby boosting employee morale.
Trang 17Implementing a pay structure based on work experience is justified Employees with more experience should receive higher salaries compared to less experienced ones, fostering long-term commitment to the company.
Current wage structures do not reflect the educational levels of employees adequately For instance, individuals with doctorates may earn less than those with only bachelor's degrees, leading to a sense of unfairness Given the effort required to attain higher qualifications, it's crucial for businesses to align salaries with educational achievements to ensure long-term employee retention The observation that some employees, despite not being assigned work, receive equal or higher pay than their actively working counterparts, suggests a need for businesses to refine their salary distribution policies This will prevent disparities where more diligent workers are compensated less than those with less workload.
Case Study 2: Specialty Toys
1 Demand distribution for teddy bears is a normal probability distribution with confidence interval.
10000 < μ < 30000 = 1 - α = 90%
μ=x = 30000 + 2 10000 =20000
P (x < 30000) = 95%
⇔ P ( x −20000 σ < 30000 − 20000
σ ) = 95%
P (z < z ) = 95% ⇒ °
⇔ 30000 − 20000
σ = 6060 ⇔
2 Probability for the stock – out is probability for demand > order.
P (x > k) = P (z > k −20000 6060 ) = 1 – P (z < k −20000 6060 )
Order Probability [1 – P (z < k −20000
6060 )]
Trang 1828000 0,0934
3 Sell teddy bears for $24 and cost $16 per unit.
Profit per unit: 24 – 16 = $8 ⇒
All surplus inventory for $5 per unit
Loss in profit per unit: 5 – 16 = -11 ⇒
We have projected profit in the following table:
15000 8 x 10000 – 11 x 5000
= 25000
8 x 15000 = 120000
12000 0
18000 8 x 10000 – 11 x 8000
= -8000
8 x 18000 = 144000
14400 0
24000 8 x 10000 – 11 x 14000
= -74000
8 x 20000 – 11 x
4000 = 116000
19200 0
28000 8 x 10000 – 11 x 18000
= -118000
8 x 20000 – 11 x
8000 = 72000
22400 0
4 The order quantities meet 70%, and 30% chance of stock – out.
⇔ P (x < x ) = 70% °
P (z < ⇔ x ° −20000
6060 ) = 0,7
⇔ x ° −20000
6060 = 0,5244
x = 23177,864 ≈ 23178 ⇔ °
Profit if sales = 10000
P = 10000 x 8 – 11 x 13178 = -64958
Profit if sales = 20000
P = 20000 x 8 – 11 x 3178 = 125042
Profit if sales = 30000
P = 23178 x 8 = 185424
Trang 195 Provide your own recommendation for an order quantity and note the associated profit projections Provide a rationale for your recommendation.
● According to the case and the above calculation, we get:
· underage cost: (Cu) = 24 – 16 = 8
· overage cost (Co)=16 – (16 – 5) = 5.
● According to the formula: Cu P(z)= Cu + Co
P(z)= 8 8 +5 = 0.62
● In the standard normal distribution function table, we find: P (z ≤ 0.31) = 0.5 + 0.12172 = 0.62172
● 0.62172 is the probability value closest to 0.62.
● According to the formula: z = x −μ
σ
● x= z *σ +μ = 0.31 × 6060 + 20000 = 21879
⇒ Hence, we would recommend Specialty Toys to have an order quantity of 21,879 because it will maximize the company’s profit.