Week 3	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
At this point we know the following about male and female salaries.	 	 	 	 	 	 	 	 	 	 	 
a.	Male and female overall average salaries are not equal in the population.	 	 	 	 	 	 	 	 	 
b.	Male and female overall average compas are equal in the population, but males are a bit more spread out.	 	 	 	 	 	 
c.	The male and female salary range are almost the same, as is their age and service.	 	 	 	 	 	 	 	 
d. 	Average performance ratings per gender are equal.	 	 	 	 	 	 	 	 	 	 
Let's look at some other factors that might influence pay - education(degree) and performance ratings.	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
1	Last week, we found that average performance ratings do not differ between males and females in the population.	 	 	 	 	 
 	Now we need to see if they differ among the grades. Is the average performace rating the same for all grades?	 	 	 	 	 
 	(Assume variances are equal across the grades for this ANOVA.)	 	A	B	C	D	E	F	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Null Hypothesis:	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Alt. Hypothesis:	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Place  B17 in Outcome range box.	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Interpretation:	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	What is the p-value:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Is P-value < 0.05?	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Do we REJ or Not reject the null?	 	 	 	 	 	 	 	 	 	 
 	If  the null hypothesis was rejected, what is the effect size value (eta squared):	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Meaning of effect size measure:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	What does that decision mean in terms of our equal pay question:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
2	While it appears that average salaries per each grade differ, we need to test this assumption.	 	 	 	 	 	 	 
 	 Is the average salary the same for each of the grade levels? (Assume equal variance, and use the analysis toolpak function ANOVA.)  	 	 	 
 	Use the input table to the right to list salaries under each grade level.	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Null Hypothesis:	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Alt. Hypothesis:	 	 	 	 	 	 	A	B	C	D	E	F	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Place  B55 in Outcome range box.	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	What is the p-value:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Is P-value < 0.05?	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Do you reject or not reject the null hypothesis:	 	 	 	 	 	 	 	 	 	 
 	If  the null hypothesis was rejected, what is the effect size value (eta squared):	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Meaning of effect size measure:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Interpretation:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
3	The table and analysis below demonstrate a 2-way ANOVA with replication.  Please interpret the results.	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	BA	MA	 	Ho: Average compas by gender are equal	 	 	 	 	 	 	 
 	Male	1.017	1.157	 	Ha: Average compas by gender are not equal	 	 	 	 	 	 	 
 	 	0.870	0.979	 	Ho: Average compas are equal for each degree	 	 	 	 	 	 
 	 	1.052	1.134	 	Ho: Average compas are not equal for each degree	 	 	 	 	 	 
 	 	1.175	1.149	 	Ho: Interaction is not significant	 	 	 	 	 	 	 	 
 	 	1.043	1.043	 	Ha: Interaction is significant	 	 	 	 	 	 	 	 
 	 	1.074	1.134	 	 	 	 	 	 	 	 	 	 	 	 
 	 	1.020	1.000	 	Perform analysis:	 	 	 	 	 	 	 	 	 
 	 	0.903	1.122	 	 	 	 	 	 	 	 	 	 	 	 
 	 	0.982	0.903	 	Anova: Two-Factor With Replication	 	 	 	 	 	 	 	 
 	 	1.086	1.052	 	 	 	 	 	 	 	 	 	 	 	 
 	 	1.075	1.140	 	SUMMARY	BA	MA	Total	 	 	 	 	 	 	 
 	 	1.052	1.087	 	Male	 	 	 	 	 	 	 	 	 	 
 	Female	1.096	1.050	 	Count	12	12	24	 	 	 	 	 	 	 
 	 	1.025	1.161	 	Sum	12.349	12.9	25.249	 	 	 	 	 	 	 
 	 	1.000	1.096	 	Average	1.02908333	1.075	1.052042	 	 	 	 	 	 	 
 	 	0.956	1.000	 	Variance	0.00668645	0.00652	0.006866	 	 	 	 	 	 	 
 	 	1.000	1.041	 	 	 	 	 	 	 	 	 	 	 	 
 	 	1.043	1.043	 	Female	 	 	 	 	 	 	 	 	 	 
 	 	1.043	1.119	 	Count	12	12	24	 	 	 	 	 	 	 
 	 	1.210	1.043	 	Sum	12.791	12.787	25.578	 	 	 	 	 	 	 
 	 	1.187	1.000	 	Average	1.06591667	1.065583	1.06575	 	 	 	 	 	 	 
 	 	1.043	0.956	 	Variance	0.00610245	0.004213	0.004933	 	 	 	 	 	 	 
 	 	1.043	1.129	 	 	 	 	 	 	 	 	 	 	 	 
 	 	1.145	1.149	 	Total	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Count	24	24	 	 	 	 	 	 	 	 
 	 	 	 	 	Sum	25.14	25.687	 	 	 	 	 	 	 	 
 	 	 	 	 	Average	1.0475	1.070292	 	 	 	 	 	 	 	 
 	 	 	 	 	Variance	0.00647035	0.005156	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	ANOVA	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Source of Variation	SS	df	MS	F	P-value	F crit	 	 	 	 
 	 	 	 	 	Sample	0.00225502	1	0.002255	0.383482	0.538939	4.061706	  (This is the row variable or gender.)
 	 	 	 	 	Columns	0.00623352	1	0.006234	1.060054	0.30883	4.061706	  (This is the column variable or Degree.)
 	 	 	 	 	Interaction	0.00641719	1	0.006417	1.091288	0.301892	4.061706	 	 	 	 
 	 	 	 	 	Within	0.25873675	44	0.00588	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Total	0.27364248	47	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Interpretation:	 	 	 	 	 	 	 	 	 	 	 	 	 	 
For Ho: Average compas by gender are equal	Ha: Average compas by gender are not equal	 	 	 	 	 	 	 
 	 	 	 	 	What is the p-value:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Is P-value < 0.05?	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Do you reject or not reject the null hypothesis:	 	 	 	 	 	 	 	 	 	 
 	If  the null hypothesis was rejected, what is the effect size value (eta squared):	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Meaning of effect size measure:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
For Ho: Average salaries are equal for all grades  	Ha: Average salaries are not equal for all grades	 	 	 	 	 	 
 	 	 	 	 	What is the p-value:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Is P-value < 0.05?	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Do you reject or not reject the null hypothesis:	 	 	 	 	 	 	 	 	 	 
 	If  the null hypothesis was rejected, what is the effect size value (eta squared):	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Meaning of effect size measure:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	For: Ho: Interaction is not significant	Ha: Interaction is significant	 	 	 	 	 	 	 	 	 
 	 	 	 	 	What is the p-value:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Do you reject or not reject the null hypothesis:	 	 	 	 	 	 	 	 	 	 
 	If  the null hypothesis was rejected, what is the effect size value (eta squared):	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	Meaning of effect size measure:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	What do these decisions mean in terms of our equal pay question:	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
4	Many companies consider the grade midpoint to be the "market rate" - what is needed to hire a new employee.	 	 	Midpoint	Salary	 
 	Does the company, on average, pay its existing employees at or above the market rate?	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Null Hypothesis:	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Alt. Hypothesis:	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	Statistical test to use:	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Place  the cursor in B160 for correl.	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	What is the p-value:	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	Is P-value < 0.05?	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	Do we REJ or Not reject the null?	 	 	 	 	 	 	 	 	 	 	 	 	 
If  the null hypothesis was rejected, what is the effect size value:	Since the effect size was not discussed in this chapter, we do not have a formula for it - it differs from the non-paired t.	 	 	 	 	 	 	 	 
 	 	Meaning of effect size measure:	NA	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	Interpretation:	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 
5.  	 Using the results up thru this week, what are your conclusions about gender equal pay for equal work at this point?