Bus 308
Ashford 5: - Week 4 - Discussion 1
Your initial discussion thread is due on Day 3 (Thursday) and you have until Day 7 (Monday) to respond to your classmates. Your grade will reflect both the quality of your initial post and the depth of your responses. Reference the Discussion Forum Grading Rubric for guidance on how your discussion will be evaluated.
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Confidence Intervals |
Many people do not “like” or “trust” single point estimates for things they need measured. Looking back at the data examples you have provided in the previous discussion questions on this issue, how might adding confidence intervals help managers accept the results better? Why?
Ask a manger in your organization if they would prefer a single point estimate or a range for important measures, and why? Please share what they say. Guided Response: Review several of your classmates’ posts. Respond to at least two classmates by commenting on whether or not you think adding or using confidence intervals would result in greater acceptance. Explain if you agree or disagree with the role of a confidence interval in the interpretation of the answer.
Ashford 5: - Week 4 - Discussion 2
Your initial discussion thread is due on Day 3 (Thursday) and you have until Day 7 (Monday) to respond to your classmates. Your grade will reflect both the quality of your initial post and the depth of your responses. Reference the Discussion Forum Grading Rubric for guidance on how your discussion will be evaluated.
Chi-square tests are great to show if distributions differ or if two variables interact in producing outcomes. What are some examples of variables that you might want to check using the chi-square tests? What would these results tell you?
Guided Response: Review several of your classmates’ posts. Respond to at least two classmates by commenting on how this information might be used to make business decisions.
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See comments at the right of the data set. |
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ID |
Salary |
Compa |
Midpoint |
Age |
Performance Rating |
Service |
Gender |
Raise |
Degree |
Gender1 |
Grade |
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8 |
23 |
1.000 |
23 |
32 |
90 |
9 |
1 |
5.8 |
0 |
F |
A |
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The ongoing question that the weekly assignments will focus on is: Are males and females paid the same for equal work (under the Equal Pay Act)? |
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10 |
22 |
0.956 |
23 |
30 |
80 |
7 |
1 |
4.7 |
0 |
F |
A |
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Note: to simplfy the analysis, we will assume that jobs within each grade comprise equal work. |
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11 |
23 |
1.000 |
23 |
41 |
100 |
19 |
1 |
4.8 |
0 |
F |
A |
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14 |
24 |
1.043 |
23 |
32 |
90 |
12 |
1 |
6 |
0 |
F |
A |
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The column labels in the table mean: |
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15 |
24 |
1.043 |
23 |
32 |
80 |
8 |
1 |
4.9 |
0 |
F |
A |
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ID – Employee sample number |
Salary – Salary in thousands |
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23 |
23 |
1.000 |
23 |
36 |
65 |
6 |
1 |
3.3 |
1 |
F |
A |
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Age – Age in years |
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Performance Rating – Appraisal rating (Employee evaluation score) |
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26 |
24 |
1.043 |
23 |
22 |
95 |
2 |
1 |
6.2 |
1 |
F |
A |
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Service – Years of service (rounded) |
Gender: 0 = male, 1 = female |
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31 |
24 |
1.043 |
23 |
29 |
60 |
4 |
1 |
3.9 |
0 |
F |
A |
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Midpoint – salary grade midpoint |
Raise – percent of last raise |
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35 |
24 |
1.043 |
23 |
23 |
90 |
4 |
1 |
5.3 |
1 |
F |
A |
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Grade – job/pay grade |
Degree (0= BS\BA 1 = MS) |
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36 |
23 |
1.000 |
23 |
27 |
75 |
3 |
1 |
4.3 |
1 |
F |
A |
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Gender1 (Male or Female) |
Compa - salary divided by midpoint |
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37 |
22 |
0.956 |
23 |
22 |
95 |
2 |
1 |
6.2 |
1 |
F |
A |
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42 |
24 |
1.043 |
23 |
32 |
100 |
8 |
1 |
5.7 |
0 |
F |
A |
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3 |
34 |
1.096 |
31 |
30 |
75 |
5 |
1 |
3.6 |
0 |
F |
B |
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18 |
36 |
1.161 |
31 |
31 |
80 |
11 |
1 |
5.6 |
1 |
F |
B |
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20 |
34 |
1.096 |
31 |
44 |
70 |
16 |
1 |
4.8 |
1 |
F |
B |
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39 |
35 |
1.129 |
31 |
27 |
90 |
6 |
1 |
5.5 |
1 |
F |
B |
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7 |
41 |
1.025 |
40 |
32 |
100 |
8 |
1 |
5.7 |
0 |
F |
C |
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13 |
42 |
1.050 |
40 |
30 |
100 |
2 |
1 |
4.7 |
1 |
F |
C |
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22 |
57 |
1.187 |
48 |
48 |
65 |
6 |
1 |
3.8 |
0 |
F |
D |
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24 |
50 |
1.041 |
48 |
30 |
75 |
9 |
1 |
3.8 |
1 |
F |
D |
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45 |
55 |
1.145 |
48 |
36 |
95 |
8 |
1 |
5.2 |
0 |
F |
D |
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17 |
69 |
1.210 |
57 |
27 |
55 |
3 |
1 |
3 |
0 |
F |
E |
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48 |
65 |
1.140 |
57 |
34 |
90 |
11 |
1 |
5.3 |
1 |
F |
E |
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28 |
75 |
1.119 |
67 |
44 |
95 |
9 |
1 |
4.4 |
1 |
F |
F |
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43 |
77 |
1.149 |
67 |
42 |
95 |
20 |
1 |
5.5 |
1 |
F |
F |
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19 |
24 |
1.043 |
23 |
32 |
85 |
1 |
0 |
4.6 |
1 |
M |
A |
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25 |
24 |
1.043 |
23 |
41 |
70 |
4 |
0 |
4 |
0 |
M |
A |
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40 |
25 |
1.086 |
23 |
24 |
90 |
2 |
0 |
6.3 |
0 |
M |
A |
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2 |
27 |
0.870 |
31 |
52 |
80 |
7 |
0 |
3.9 |
0 |
M |
B |
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32 |
28 |
0.903 |
31 |
25 |
95 |
4 |
0 |
5.6 |
0 |
M |
B |
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34 |
28 |
0.903 |
31 |
26 |
80 |
2 |
0 |
4.9 |
1 |
M |
B |
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16 |
47 |
1.175 |
40 |
44 |
90 |
4 |
0 |
5.7 |
0 |
M |
C |
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27 |
40 |
1.000 |
40 |
35 |
80 |
7 |
0 |
3.9 |
1 |
M |
C |
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41 |
43 |
1.075 |
40 |
25 |
80 |
5 |
0 |
4.3 |
0 |
M |
C |
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5 |
47 |
0.979 |
48 |
36 |
90 |
16 |
0 |
5.7 |
1 |
M |
D |
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30 |
49 |
1.020 |
48 |
45 |
90 |
18 |
0 |
4.3 |
0 |
M |
D |
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1 |
58 |
1.017 |
57 |
34 |
85 |
8 |
0 |
5.7 |
0 |
M |
E |
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4 |
66 |
1.157 |
57 |
42 |
100 |
16 |
0 |
5.5 |
1 |
M |
E |
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12 |
60 |
1.052 |
57 |
52 |
95 |
22 |
0 |
4.5 |
0 |
M |
E |
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33 |
64 |
1.122 |
57 |
35 |
90 |
9 |
0 |
5.5 |
1 |
M |
E |
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38 |
56 |
0.982 |
57 |
45 |
95 |
11 |
0 |
4.5 |
0 |
M |
E |
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44 |
60 |
1.052 |
57 |
45 |
90 |
16 |
0 |
5.2 |
1 |
M |
E |
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46 |
65 |
1.140 |
57 |
39 |
75 |
20 |
0 |
3.9 |
1 |
M |
E |
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47 |
62 |
1.087 |
57 |
37 |
95 |
5 |
0 |
5.5 |
1 |
M |
E |
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49 |
60 |
1.052 |
57 |
41 |
95 |
21 |
0 |
6.6 |
0 |
M |
E |
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50 |
66 |
1.157 |
57 |
38 |
80 |
12 |
0 |
4.6 |
0 |
M |
E |
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6 |
76 |
1.134 |
67 |
36 |
70 |
12 |
0 |
4.5 |
1 |
M |
F |
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9 |
77 |
1.149 |
67 |
49 |
100 |
10 |
0 |
4 |
1 |
M |
F |
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21 |
76 |
1.134 |
67 |
43 |
95 |
13 |
0 |
6.3 |
1 |
M |
F |
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29 |
72 |
1.074 |
67 |
52 |
95 |
5 |
0 |
5.4 |
0 |
M |
F |
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Score: |
Week 4 |
Confidence Intervals and Chi Square (Chs 11 - 12) |
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For questions 3 and 4 below, be sure to list the null and alternate hypothesis statements. Use .05 for your significance level in making your decisions. |
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For full credit, you need to also show the statistical outcomes - either the Excel test result or the calculations you performed. |
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<1 point> |
1 |
Using our sample data, construct a 95% confidence interval for the population's mean salary for each gender. |
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Interpret the results. How do they compare with the findings in the week 2 one sample t-test outcomes (Question 1)? |
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Mean |
St error |
t value |
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Low |
to |
High |
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Males |
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Females |
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<Reminder: standard error is the sample standard deviation divided by the square root of the sample size.> |
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Interpretation: |
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<1 point> |
2 |
Using our sample data, construct a 95% confidence interval for the mean salary difference between the genders in the population. |
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How does this compare to the findings in week 2, question 2? |
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Difference |
St Err. |
T value |
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Low |
to |
High |
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Yes/No |
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Can the means be equal? |
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Why? |
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How does this compare to the week 2, question 2 result (2 sampe t-test)? |
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a. |
Why is using a two sample tool (t-test, confidence interval) a better choice than using 2 one- sample techniques when comparing two samples? |
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<1 point> |
3 |
We found last week that the degree values within the population do not impact compa rates. |
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This does not mean that degrees are distributed evenly across the grades and genders. |
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Do males and females have athe same distribution of degrees by grade? |
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(Note: while technically the sample size might not be large enough to perform this test, ignore this limitation for this exercise.) |
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What are the hypothesis statements: |
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Ho: |
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Ha: |
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Note: You can either use the Excel Chi-related functions or do the calculations manually. |
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Data input tables - graduate degrees by gender and grade level |
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OBSERVED |
A |
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F |
Total |
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If desired, you can do manual calculations per cell here. |
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M Grad |
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Fem Grad |
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M Grad |
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Male Und |
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Fem Grad |
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Female Und |
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Male Und |
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Female Und |
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Sum = |
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EXPECTED |
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M Grad |
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For this exercise - ignore the requirement for a correction factor |
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Fem Grad |
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for cells with expected values less than 5. |
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Male Und |
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Female Und |
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Interpretation: |
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What is the value of the chi square statistic: |
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What is the p-value associated with this value: |
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Is the p-value <0.05? |
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Do you reject or not reject the null hypothesis: |
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If you rejected the null, what is the Cramer's V correlation: |
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What does this correlation mean? |
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What does this decision mean for our equal pay question: |
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<1 point> |
4 |
Based on our sample data, can we conclude that males and females are distributed across grades in a similar pattern |
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within the population? |
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What are the hypothesis statements: |
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Ho: |
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Ha: |
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Do manual calculations per cell here (if desired) |
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A |
B |
C |
D |
E |
F |
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D |
E |
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OBS COUNT - m |
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M |
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OBS COUNT - f |
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F |
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Sum = |
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EXPECTED |
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What is the value of the chi square statistic: |
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What is the p-value associated with this value: |
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Is the p-value <0.05? |
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Do you reject or not reject the null hypothesis: |
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If you rejected the null, what is the Phi correlation: |
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What does this correlation mean? |
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What does this decision mean for our equal pay question: |
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<2 points> |
5. How do you interpret these results in light of our question about equal pay for equal work? |
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