week three problem set
Data
| ID | Salary | Compa-ratio | Midpoint | Age | Performance Rating | Service | Gender | Raise | Degree | Gender1 | Grade | Do not manipuilate Data set on this page, copy to another page to make changes | ||||
| 1 | 54.5 | 0.956 | 57 | 34 | 85 | 8 | 0 | 5.7 | 0 | M | E | 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)? | ||||
| 2 | 28.3 | 0.913 | 31 | 52 | 80 | 7 | 0 | 3.9 | 0 | M | B | Note: to simplfy the analysis, we will assume that jobs within each grade comprise equal work. | ||||
| 3 | 34.1 | 1.100 | 31 | 30 | 75 | 5 | 1 | 3.6 | 1 | F | B | |||||
| 4 | 60.9 | 1.068 | 57 | 42 | 100 | 16 | 0 | 5.5 | 1 | M | E | The column labels in the table mean: | ||||
| 5 | 49.2 | 1.025 | 48 | 36 | 90 | 16 | 0 | 5.7 | 1 | M | D | ID – Employee sample number | Salary – Salary in thousands | |||
| 6 | 74.1 | 1.106 | 67 | 36 | 70 | 12 | 0 | 4.5 | 1 | M | F | Age – Age in years | Performance Rating - Appraisal rating (employee evaluation score) | |||
| 7 | 41.4 | 1.034 | 40 | 32 | 100 | 8 | 1 | 5.7 | 1 | F | C | Service – Years of service (rounded) | Gender – 0 = male, 1 = female | |||
| 8 | 22.8 | 0.992 | 23 | 32 | 90 | 9 | 1 | 5.8 | 1 | F | A | Midpoint – salary grade midpoint | Raise – percent of last raise | |||
| 9 | 73 | 1.089 | 67 | 49 | 100 | 10 | 0 | 4 | 1 | M | F | Grade – job/pay grade | Degree (0= BS\BA 1 = MS) | |||
| 10 | 23.3 | 1.014 | 23 | 30 | 80 | 7 | 1 | 4.7 | 1 | F | A | Gender1 (Male or Female) | Compa-ratio - salary divided by midpoint | |||
| 11 | 24.3 | 1.057 | 23 | 41 | 100 | 19 | 1 | 4.8 | 1 | F | A | |||||
| 12 | 59.7 | 1.047 | 57 | 52 | 95 | 22 | 0 | 4.5 | 0 | M | E | |||||
| 13 | 41.8 | 1.044 | 40 | 30 | 100 | 2 | 1 | 4.7 | 0 | F | C | |||||
| 14 | 25 | 1.085 | 23 | 32 | 90 | 12 | 1 | 6 | 1 | F | A | |||||
| 15 | 22.6 | 0.983 | 23 | 32 | 80 | 8 | 1 | 4.9 | 1 | F | A | |||||
| 16 | 48.5 | 1.213 | 40 | 44 | 90 | 4 | 0 | 5.7 | 0 | M | C | |||||
| 17 | 63.1 | 1.107 | 57 | 27 | 55 | 3 | 1 | 3 | 1 | F | E | |||||
| 18 | 36.2 | 1.167 | 31 | 31 | 80 | 11 | 1 | 5.6 | 0 | F | B | |||||
| 19 | 23.9 | 1.039 | 23 | 32 | 85 | 1 | 0 | 4.6 | 1 | M | A | |||||
| 20 | 35.5 | 1.144 | 31 | 44 | 70 | 16 | 1 | 4.8 | 0 | F | B | |||||
| 21 | 78.9 | 1.178 | 67 | 43 | 95 | 13 | 0 | 6.3 | 1 | M | F | |||||
| 22 | 57.6 | 1.199 | 48 | 48 | 65 | 6 | 1 | 3.8 | 1 | F | D | |||||
| 23 | 22.2 | 0.964 | 23 | 36 | 65 | 6 | 1 | 3.3 | 0 | F | A | |||||
| 24 | 53.4 | 1.112 | 48 | 30 | 75 | 9 | 1 | 3.8 | 0 | F | D | |||||
| 25 | 23.6 | 1.028 | 23 | 41 | 70 | 4 | 0 | 4 | 0 | M | A | |||||
| 26 | 22.3 | 0.971 | 23 | 22 | 95 | 2 | 1 | 6.2 | 0 | F | A | |||||
| 27 | 46.2 | 1.156 | 40 | 35 | 80 | 7 | 0 | 3.9 | 1 | M | C | |||||
| 28 | 74.4 | 1.111 | 67 | 44 | 95 | 9 | 1 | 4.4 | 0 | F | F | |||||
| 29 | 75.6 | 1.129 | 67 | 52 | 95 | 5 | 0 | 5.4 | 0 | M | F | |||||
| 30 | 47.5 | 0.989 | 48 | 45 | 90 | 18 | 0 | 4.3 | 0 | M | D | |||||
| 31 | 22.9 | 0.995 | 23 | 29 | 60 | 4 | 1 | 3.9 | 1 | F | A | |||||
| 32 | 28.1 | 0.906 | 31 | 25 | 95 | 4 | 0 | 5.6 | 0 | M | B | |||||
| 33 | 63.7 | 1.117 | 57 | 35 | 90 | 9 | 0 | 5.5 | 1 | M | E | |||||
| 34 | 26.9 | 0.869 | 31 | 26 | 80 | 2 | 0 | 4.9 | 1 | M | B | |||||
| 35 | 22.7 | 0.987 | 23 | 23 | 90 | 4 | 1 | 5.3 | 0 | F | A | |||||
| 36 | 24.4 | 1.059 | 23 | 27 | 75 | 3 | 1 | 4.3 | 0 | F | A | |||||
| 37 | 23.8 | 1.034 | 23 | 22 | 95 | 2 | 1 | 6.2 | 0 | F | A | |||||
| 38 | 64.6 | 1.133 | 57 | 45 | 95 | 11 | 0 | 4.5 | 0 | M | E | |||||
| 39 | 37.3 | 1.202 | 31 | 27 | 90 | 6 | 1 | 5.5 | 0 | F | B | |||||
| 40 | 23.7 | 1.031 | 23 | 24 | 90 | 2 | 0 | 6.3 | 0 | M | A | |||||
| 41 | 40.3 | 1.008 | 40 | 25 | 80 | 5 | 0 | 4.3 | 0 | M | C | |||||
| 42 | 24.4 | 1.059 | 23 | 32 | 100 | 8 | 1 | 5.7 | 1 | F | A | |||||
| 43 | 72.3 | 1.079 | 67 | 42 | 95 | 20 | 1 | 5.5 | 0 | F | F | |||||
| 44 | 65.9 | 1.156 | 57 | 45 | 90 | 16 | 0 | 5.2 | 1 | M | E | |||||
| 45 | 49.9 | 1.040 | 48 | 36 | 95 | 8 | 1 | 5.2 | 1 | F | D | |||||
| 46 | 57.4 | 1.007 | 57 | 39 | 75 | 20 | 0 | 3.9 | 1 | M | E | |||||
| 47 | 56 | 0.982 | 57 | 37 | 95 | 5 | 0 | 5.5 | 1 | M | E | |||||
| 48 | 68.1 | 1.195 | 57 | 34 | 90 | 11 | 1 | 5.3 | 1 | F | E | |||||
| 49 | 66.2 | 1.161 | 57 | 41 | 95 | 21 | 0 | 6.6 | 0 | M | E | |||||
| 50 | 61.7 | 1.083 | 57 | 38 | 80 | 12 | 0 | 4.6 | 0 | M | E |
Week 1
| Week 1: Descriptive Statistics, including Probability | Gender1 | Salary | ||||||||||||||||||
| While the lectures will examine our equal pay question from the compa-ratio viewpoint, our weekly assignments will focus on | F | 34.1 | ||||||||||||||||||
| examining the issue using the salary measure. | F | 41.4 | ||||||||||||||||||
| F | 22.8 | |||||||||||||||||||
| The purpose of this assignmnent is two fold: | F | 23.3 | ||||||||||||||||||
| 1. Demonstrate mastery with Excel tools. | F | 24.3 | ||||||||||||||||||
| 2. Develop descriptive statistics to help examine the question. | F | 41.8 | ||||||||||||||||||
| 3. Interpret descriptive outcomes | F | 25 | ||||||||||||||||||
| F | 22.6 | |||||||||||||||||||
| The first issue in examining salary data to determine if we - as a company - are paying males and females equally for doing equal work is to develop some | F | 63.1 | ||||||||||||||||||
| descriptive statistics to give us something to make a preliminary decision on whether we have an issue or not. | F | 36.2 | ||||||||||||||||||
| F | 35.5 | |||||||||||||||||||
| 1 | Descriptive Statistics: Develop basic descriptive statistics for Salary | F | 57.6 | |||||||||||||||||
| The first step in analyzing data sets is to find some summary descriptive statistics for key variables. | F | 22.2 | ||||||||||||||||||
| Suggestion: Copy the gender1 and salary columns from the Data tab to columns T and U at the right. | F | 53.4 | ||||||||||||||||||
| Then use Data Sort (by gender1) to get all the male and female salary values grouped together. | F | 22.3 | ||||||||||||||||||
| F | 74.4 | |||||||||||||||||||
| a. | Use the Descriptive Statistics function in the Data Analysis tab | Place Excel outcome in Cell K19 | F | 22.9 | ||||||||||||||||
| to develop the descriptive statistics summary for the overall | Column1 | F | 22.7 | |||||||||||||||||
| group's overall salary. (Place K19 in output range.) | F | 24.4 | ||||||||||||||||||
| Highlight the mean, sample standard deviation, and range. | Mean | 44.884 | F | 23.8 | ||||||||||||||||
| Standard Error | 2.6698167177 | F | 37.3 | |||||||||||||||||
| Median | 44 | F | 24.4 | |||||||||||||||||
| Mode | 24.4 | F | 72.3 | |||||||||||||||||
| b. | Using Fx (or formula) functions find the following (be sure to show the formula | 18.8784550561 | Standard Deviation | 18.8784550561 | F | 49.9 | ||||||||||||||
| and not just the value in each cell) asked for salary statistics for each gender: | Sample Variance | 356.3960653061 | F | 68.1 | ||||||||||||||||
| Male | Female | Kurtosis | -1.4241756975 | M | 54.5 | |||||||||||||||
| Mean: | 51.936 | 37.832 | Skewness | 0.2096662654 | M | 28.3 | ||||||||||||||
| Sample Standard Deviation: | 17.7426247588 | 17.5850959622 | Range | 56.7 | M | 60.9 | ||||||||||||||
| Range: | 55.3 | 52.2 | Minimum | 22.2 | M | 49.2 | ||||||||||||||
| Maximum | 78.9 | M | 74.1 | |||||||||||||||||
| Sum | 2244.2 | M | 73 | |||||||||||||||||
| Count | 50 | M | 59.7 | |||||||||||||||||
| M | 48.5 | |||||||||||||||||||
| 2 | Develop a 5-number summary for the overall, male, and female SALARY variable. | M | 23.9 | |||||||||||||||||
| For full credit, use the excel formulas in each cell rather than simply the numerical answer. | M | 78.9 | ||||||||||||||||||
| Overall | Males | Females | M | 23.6 | ||||||||||||||||
| Max | 78.9 | 78.9 | 74.4 | M | 46.2 | |||||||||||||||
| 3rd Q | 61.5 | 64.6 | 49.9 | M | 75.6 | |||||||||||||||
| Midpoint | 44 | 56 | 34.1 | M | 47.5 | |||||||||||||||
| 1st Q | 24.4 | 40.3 | 23.3 | M | 28.1 | |||||||||||||||
| Min | 44.4 | 23.6 | 22.2 | 0 | M | 63.7 | ||||||||||||||
| 0.37 | M | 26.9 | ||||||||||||||||||
| 3 | Location Measures: comparing Male and Female midpoints to the overall Salary data range. | M | 64.6 | |||||||||||||||||
| For full credit, show the excel formulas in each cell rather than simply the numerical answer. | M | 23.7 | ||||||||||||||||||
| Using the entire Salary range and the M and F midpoints found in Q2 | Male | Female | M | 40.3 | ||||||||||||||||
| a. What would each midpoint's percentile rank be in the overall range? | 0.64 | 0.37 | Use Excel's =PERCENTRANK.EXC function | M | 65.9 | |||||||||||||||
| b. What is the normal curve z value for each midpoint within overall range? | 0.5888 | -0.5712 | Use Excel's =STANDARDIZE function | M | 57.4 | |||||||||||||||
| M | 56 | |||||||||||||||||||
| 4 | Probability Measures: comparing Male and Female midpoints to the overall Salary data range | 0.64 | M | 66.2 | ||||||||||||||||
| For full credit, show the excel formulas in each cell rather than simply the numerical answer. | M | 61.7 | ||||||||||||||||||
| Using the entire Salary range and the M and F midpoints found in Q2, find | Male | Female | ||||||||||||||||||
| a. The Empirical Probability of equaling or exceeding (=>) that value for | 0.36 | 0.64 | Show the calculation formula = value/50 or =countif(range,">="&cell)/50 | |||||||||||||||||
| b. The Normal curve Prob of => that value for each group | 0.3594235668 | 0.2610862997 | Use "=1-NORM.S.DIST" function | |||||||||||||||||
| Note: be sure to use the ENTIRE salary range for part a when finding the probability. | ||||||||||||||||||||
| 5 | Conclusions: What do you make of these results? | Be sure to include findings from this week's lectures as well. | ||||||||||||||||||
| In comparing the overall, male, and female outcomes, what relationship(s) see, to exist between the data sets? | ||||||||||||||||||||
| Your findings: | it is my finding that half the males make more than the females and the other half of the males make less than the females. Of the 56 | compared to the statistical prediction | ||||||||||||||||||
| The lecture's related findings: | the lecture makes that argument that all the males make a larger salary but that is not the case. | |||||||||||||||||||
| Overall conclusion: | is after you range and midpoint to figure out the number of people that make larger salary and how many make less than female in the company | |||||||||||||||||||
| What does this suggest about our equal pay for equal work question? | ||||||||||||||||||||
Week 2
| Week 2: Identifying Significant Differences - part 1 | Salary | Compa-ratio | |||||||||||||||
| Male | Femael | Male | Female | ||||||||||||||
| To Ensure full credit for each question, you need to show how you got your results. This involves either showing where the data you used is located | 54.5 | 34.1 | 0.956 | 1.100 | |||||||||||||
| or showing the excel formula in each cell. | Be sure to copy the appropriate data columns from the data tab to the right for your use this week. | 28.3 | 41.4 | 0.913 | 1.034 | ||||||||||||
| 60.9 | 22.8 | 1.068 | 0.992 | ||||||||||||||
| As with our examination of compa-ratio in the lecture, the first question we have about salary between the genders involves equality - are they the same or different? | 49.2 | 23.3 | 1.025 | 1.014 | |||||||||||||
| What we do, depends upon our findings. | 74.1 | 24.3 | 1.106 | 1.057 | |||||||||||||
| 73 | 41.8 | 1.089 | 1.044 | ||||||||||||||
| 1 | As with the compa-ratio lecture example, we want to examine salary variation within the groups - are they equal? | Use Cell K10 for the Excel test outcome location. | 59.7 | 25 | 1.047 | 1.085 | |||||||||||
| a | What is the data input ranged used for this question: | F-Test Two-Sample for Variances | 48.5 | 22.6 | 1.213 | 0.983 | |||||||||||
| Q3:Q27 | and | R3:R27 | 23.9 | 63.1 | 1.039 | 1.107 | |||||||||||
| b | Which is needed for this question: a one- or two-tail hypothesis statement and test ? | Male | Female | 78.9 | 36.2 | 1.178 | 1.167 | ||||||||||
| Answer: | I would pick the one tail hypothesis | Mean | 1.05556 | 1.06936 | 23.6 | 35.5 | 1.028 | 1.144 | |||||||||
| Why: | We are only trying to prove that they are not equal | Variance | 0.0081384233 | 0.0052293233 | 46.2 | 57.6 | 1.156 | 1.199 | |||||||||
| Observations | 25 | 25 | 75.6 | 22.2 | 1.129 | 0.964 | |||||||||||
| c. Step 1: | Ho: | Male compa-ratio variance equl Female compa-ratio variance | df | 24 | 24 | 47.5 | 53.4 | 0.989 | 1.112 | ||||||||
| Ha: | Male compa-ratio variance not equl Female compa-ratio variance | F | 1.5563052454 | 28.1 | 22.3 | 0.906 | 0.971 | ||||||||||
| Step 2: | Significance (Alpha): | 0.05 | P(F<=f) one-tail | 0.1427728797 | 63.7 | 74.4 | 1.117 | 1.111 | |||||||||
| Step 3: | Test Statistic and test: | F statistic and F-test for Variance | F Critical one-tail | 1.9837595685 | 26.9 | 22.9 | 0.869 | 0.995 | |||||||||
| Why this test? | Need to determine the mean and significantly different | 64.6 | 22.7 | 1.133 | 0.987 | ||||||||||||
| Step 4: | Decision rule: | Decision rule: Reject the null hypothesis if the p-value is less than 0.05 | 23.7 | 24.4 | 1.031 | 1.059 | |||||||||||
| Step 5: | Conduct the test - place test function in cell k10 | 40.3 | 23.8 | 1.008 | 1.034 | ||||||||||||
| 65.9 | 37.3 | 1.156 | 1.202 | ||||||||||||||
| Step 6: | Conclusion and Interpretation | 57.4 | 24.4 | 1.007 | 1.059 | ||||||||||||
| What is the p-value: | 0.1427728797 | 56 | 72.3 | 0.982 | 1.079 | ||||||||||||
| What is your decision: REJ or NOT reject the null? | Not Reject | 66.2 | 49.9 | 1.161 | 1.040 | ||||||||||||
| Why? | p value is greater than alpha | 61.7 | 68.1 | 1.083 | 1.195 | ||||||||||||
| What is your conclusion about the variance in the population for male and female salaries? | Conclude that Male compa-ratio variance equl Female compa-ratio variance | ||||||||||||||||
| 2 | Once we know about variance quality, we can move on to means: Are male and female average salaries equal? | Use Cell K35 for the Excel test outcome location. | |||||||||||||||
| (Regardless of the outcome of the above F-test, assume equal variances for this test.) | |||||||||||||||||
| a | What is the data input ranged used for this question: | F-Test Two-Sample for Variances | |||||||||||||||
| 03:027 | and | P3:P27 | |||||||||||||||
| b | Does this question need a one or two-tail hypothesis statement and test? | two tail hypothesis | Male | Femael | |||||||||||||
| Why: | We trying to prove that they are not equal | Mean | 51.936 | 37.832 | |||||||||||||
| c. Step 1: | Ho: | male salary average=female salary average | Variance | 314.8007333333 | 309.2356 | ||||||||||||
| Ha: | male salary average=/female salary average | Observations | 25 | 25 | |||||||||||||
| Step 2: | Significance (Alpha): | 0.05 | df | 24 | 24 | ||||||||||||
| Step 3: | Test Statistic and test: | F-test | F | 1.0179964187 | |||||||||||||
| Why this test? | because we are dealing with two tail | P(F<=f) one-tail | 0.4827562326 | ||||||||||||||
| Step 4: | Decision rule: | Reject the null hypothesis if the p-value is less than our alpha of .05 | F Critical one-tail | 1.9837595685 | |||||||||||||
| Step 5: | Conduct the test - place test function in cell K35 | P(F<=f) 2-tail | 0.9655124652 | ||||||||||||||
| Step 6: | Conclusion and Interpretation | ||||||||||||||||
| What is the p-value: | 0.9655124652 | ||||||||||||||||
| What is your decision: REJ or NOT reject the null? | Not Reject | ||||||||||||||||
| Why? | p value is greater than alpha (0.05) | ||||||||||||||||
| What is your conclusion about the means in the population for male and female salaries? | |||||||||||||||||
| Cocnclude that male salary average is equal female salary average | |||||||||||||||||
| The means did not equal at all . The males had a higher variance as well | |||||||||||||||||
| 3 | Education is often a factor in pay differences. | ||||||||||||||||
| Do employees with an advanced degree (degree = 1) have higher average salaries? | Use Cell K60 for the Excel test outcome location. | Degree | |||||||||||||||
| Note: assume equal variance for the salaries in each degree for this question. | 0 | 1 | |||||||||||||||
| a | What is the data input ranged used for this question: | t-Test: Paired Two Sample for Means | Salary 0 | Salary 1 | |||||||||||||
| N59:N83 | and | O59:O83 | 54.5 | 34.1 | |||||||||||||
| b | Does this question need a one or two-tail hypothesis statement and test? | one tail | Salary 0 | Salary1 | 28.3 | 60.9 | |||||||||||
| Why: | We are only looking at who has a degree or not | Mean | 43.544 | 46.224 | 59.7 | 49.2 | |||||||||||
| c. Step 1: | Ho: | degree have equal average salaries | Variance | 339.2742333333 | 384.6269 | 41.8 | 74.1 | ||||||||||
| Ha: | degree have higher average salaries | Observations | 25 | 25 | 48.5 | 41.4 | |||||||||||
| Step 2: | Significance (Alpha): | 0.05 | Pearson Correlation | 0.1040068904 | 36.2 | 22.8 | |||||||||||
| Step 3: | Test Statistic and test: | t-Test: Paired Two Sample for Means | Hypothesized Mean Difference | 0 | 35.5 | 73 | |||||||||||
| Why this test? | because of the infomration in use | df | 24 | 22.2 | 23.3 | ||||||||||||
| Step 4: | Decision rule: | Reject the null hypothesis if the p-value is less than our alpha of .05 | t Stat | -0.5260939696 | 53.4 | 24.3 | |||||||||||
| Step 5: | Conduct the test - place test function in cell K60 | P(T<=t) one-tail | 0.3018255069 | 23.6 | 25 | ||||||||||||
| t Critical one-tail | 1.7108820799 | 22.3 | 22.6 | ||||||||||||||
| Step 6: | Conclusion and Interpretation | P(T<=t) two-tail | 0.6036510137 | 74.4 | 63.1 | ||||||||||||
| What is the p-value: | 0.6036510137 | t Critical two-tail | 2.0638985616 | 75.6 | 23.9 | ||||||||||||
| Is the t value in the t-distribution tail indicated by the arrow in the Ha claim? | Yes | 47.5 | 78.9 | ||||||||||||||
| 28.1 | 57.6 | ||||||||||||||||
| What is your decision: REJ or NOT reject the null? | Not Reject | 22.7 | 46.2 | ||||||||||||||
| Why? | P value is greater than 0.05 | 24.4 | 22.9 | ||||||||||||||
| What is your conclusion about the impact of education on average salaries? | 23.8 | 63.7 | |||||||||||||||
| conclude that degree have equal average salaries | 64.6 | 26.9 | |||||||||||||||
| 37.3 | 24.4 | ||||||||||||||||
| it was shown that education had a good impart on salary with the degree mean being higher than those without | 23.7 | 65.9 | |||||||||||||||
| 40.3 | 49.9 | ||||||||||||||||
| 4 | Considering both the compa-ratio information from the lectures and your salary information, what conclusions can you reach about equal pay for equal work? | 72.3 | 57.4 | ||||||||||||||
| Your findings: | I can conclude that different factors change the salaries for different people. Those with degrees make more on average. | 66.2 | 56 | ||||||||||||||
| The lecture's related findings: | This just mean they are getting paid more because of education and experience. | 61.7 | 68.1 | ||||||||||||||
| Overall conclusion: | |||||||||||||||||
| Why - what statistical results support this conclusion? | |||||||||||||||||
| The results from question 3 supports my claims. More reseach needs to be done to determine if it is really equal pay for equal work. | |||||||||||||||||
| Or is it that they are getting rewarded for the education they have on top of the experience, which plays a factot(sometimes). | |||||||||||||||||
Sheet1
| Salary | ||
| Male | Femael | |
| 54.5 | 34.1 | |
| 28.3 | 41.4 | |
| 60.9 | 22.8 | |
| 49.2 | 23.3 | |
| 74.1 | 24.3 | |
| 73 | 41.8 | |
| 59.7 | 25 | |
| 48.5 | 22.6 | |
| 23.9 | 63.1 | |
| 78.9 | 36.2 | |
| 23.6 | 35.5 | |
| 46.2 | 57.6 | |
| 75.6 | 22.2 | |
| 47.5 | 53.4 | |
| 28.1 | 22.3 | |
| 63.7 | 74.4 | |
| 26.9 | 22.9 | |
| 64.6 | 22.7 | |
| 23.7 | 24.4 | |
| 40.3 | 23.8 | |
| 65.9 | 37.3 | |
| 57.4 | 24.4 | |
| 56 | 72.3 | |
| 66.2 | 49.9 | |
| 61.7 | 68.1 |
Week 3
| Week 3: Identifying Significant Differences - part 2 | Data Input Table: | Salary Range Groups | |||||||||||||||||||||||||
| Group name: | A | B | C | D | E | F | |||||||||||||||||||||
| To Ensure full credit for each question, you need to show how you got your results. This involves either showing where the data you used is located | List salaries within each grade | ||||||||||||||||||||||||||
| or showing the excel formula in each cell. | Be sure to copy the appropriate data columns from the data tab to the right for your use this week. | ||||||||||||||||||||||||||
| 1 | A good pay program will have different average salaries by grade. Is this the case for our company? | ||||||||||||||||||||||||||
| a | What is the data input ranged used for this question: | Use Cell K08 for the Excel test outcome location. | |||||||||||||||||||||||||
| Note: assume equal variances for each grade, even though this may not be accurate, for purposes of this question. | |||||||||||||||||||||||||||
| b. Step 1: | Ho: | ||||||||||||||||||||||||||
| Ha: | |||||||||||||||||||||||||||
| Step 2: | Significance (Alpha): | ||||||||||||||||||||||||||
| Step 3: | Test Statistic and test: | ||||||||||||||||||||||||||
| Why this test? | |||||||||||||||||||||||||||
| Step 4: | Decision rule: | ||||||||||||||||||||||||||
| Step 5: | Conduct the test - place test function in cell K08 | ||||||||||||||||||||||||||
| Step 6: | Conclusion and Interpretation | ||||||||||||||||||||||||||
| What is the p-value: | |||||||||||||||||||||||||||
| What is your decision: REJ or NOT reject the null? | |||||||||||||||||||||||||||
| Why? | |||||||||||||||||||||||||||
| What is your conclusion about the means in the population for grade salaries? | |||||||||||||||||||||||||||
| 2 | If the null hypothesis in question 1 was rejected, which pairs of means differ? | ||||||||||||||||||||||||||
| (Use the values from the ANOVA table to complete the follow table.) | |||||||||||||||||||||||||||
| Groups Compared | Mean Diff. | T value used | +/- Term | Low | to | High | Difference Significant? | Why? | |||||||||||||||||||
| A-B | |||||||||||||||||||||||||||
| A-C | |||||||||||||||||||||||||||
| A-D | |||||||||||||||||||||||||||
| A-E | |||||||||||||||||||||||||||
| A-F | |||||||||||||||||||||||||||
| B-C | |||||||||||||||||||||||||||
| B-D | |||||||||||||||||||||||||||
| B-E | |||||||||||||||||||||||||||
| B-E | |||||||||||||||||||||||||||
| C-D | |||||||||||||||||||||||||||
| C-E | |||||||||||||||||||||||||||
| C-F | |||||||||||||||||||||||||||
| D-E | |||||||||||||||||||||||||||
| D-F | |||||||||||||||||||||||||||
| E-F | |||||||||||||||||||||||||||
| 3 | One issue in salary is the grade an employee is in - higher grades have higher salaries. | ||||||||||||||||||||||||||
| This suggests that one question to ask is if males and females are distributed in a similar pattern across the salary grades? | |||||||||||||||||||||||||||
| a | What is the data input ranged used for this question: | Use Cell K54 for the Excel test outcome location. | |||||||||||||||||||||||||
| b. Step 1: | Ho: | ||||||||||||||||||||||||||
| Ha: | |||||||||||||||||||||||||||
| Step 2: | Significance (Alpha): | ||||||||||||||||||||||||||
| Step 3: | Test Statistic and test: | Place the actual distribution in the table below. | |||||||||||||||||||||||||
| Why this test? | A | B | C | D | E | F | Sum | ||||||||||||||||||||
| Step 4: | Decision rule: | Male | 0 | ||||||||||||||||||||||||
| Step 5: | Conduct the test - place test function in cell K54 | Female | 0 | ||||||||||||||||||||||||
| Sum: | 0 | 0 | 0 | 0 | 0 | 0 | 0 | ||||||||||||||||||||
| Step 6: | Conclusion and Interpretation | Place the expected distribution in the table below. | |||||||||||||||||||||||||
| What is the p-value: | A | B | C | D | E | F | |||||||||||||||||||||
| What is your decision: REJ or NOT reject the null? | Male | 0 | |||||||||||||||||||||||||
| Why? | Female | 0 | |||||||||||||||||||||||||
| What is your conclusion about the means in the population for male and female salaries? | Sum: | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||||||||||||||||||
| 4 | What implications do this week's analysis have for our equal pay question? | ||||||||||||||||||||||||||
| Your findings: | |||||||||||||||||||||||||||
| The lecture's related findings: | |||||||||||||||||||||||||||
| Overall conclusion: | |||||||||||||||||||||||||||
| Why - what statistical results support this conclusion? | |||||||||||||||||||||||||||
Week 4
| Week 4: Identifying relationships - correlations and regression | ||||||||||
| To Ensure full credit for each question, you need to show how you got your results. This involves either showing where the data you used is located | ||||||||||
| or showing the excel formula in each cell. | Be sure to copy the appropriate data columns from the data tab to the right for your use this week. | |||||||||
| 1 | What is the correlation between and among the interval/ratio level variables with salary? (Do not include compa-ratio in this question.) | |||||||||
| a. Create the correlation table. | Use Cell K08 for the Excel test outcome location. | |||||||||
| i. | What is the data input ranged used for this question: | |||||||||
| ii. | Create a correlation table in cell K08. | |||||||||
| b. Technically, we should perform a hypothesis testing on each correlation to determine | ||||||||||
| if it is significant or not. However, we can be faithful to the process and save some | ||||||||||
| time by finding the minimum correlation that would result in a two tail rejection of the null. | ||||||||||
| We can then compare each correlation to this value, and those exceeding it (in either a | ||||||||||
| positive or negative direction) can be considered statistically significant. | ||||||||||
| i. What is the t-value we would use to cut off the two tails? | T = | |||||||||
| ii. What is the associated correlation value related to this t-value? r = | ||||||||||
| c. What variable(s) is(are) significantly correlated to salary? | ||||||||||
| d. Are there any surprises - correlations you though would be significant and are not, or non significant correlations you thought would be? | ||||||||||
| e. Why does or does not this information help answer our equal pay question? | ||||||||||
| 2 | Perform a regression analysis using salary as the dependent variable and all of the variables used in Q1. Add the | |||||||||
| two dummy variables - gender and education - to your list of independent variables. Show the result, and interpret your findings by answering the following questions. | ||||||||||
| Suggestion: Add the dummy variables values to the right of the last data columns used for Q1. | ||||||||||
| What is the multiple regression equation predicting/explaining salary using all of our possible variables except compa-ratio? | ||||||||||
| a. | What is the data input ranged used for this question: | |||||||||
| b. | Step 1: State the appropriate hypothesis statements: | Use Cell M34 for the Excel test outcome location. | ||||||||
| Ho: | ||||||||||
| Ha: | ||||||||||
| Step 2: | Significance (Alpha): | |||||||||
| Step 3: | Test Statistic and test: | |||||||||
| Why this test? | ||||||||||
| Step 4: | Decision rule: | |||||||||
| Step 5: | Conduct the test - place test function in cell M34 | |||||||||
| Step 6: | Conclusion and Interpretation | |||||||||
| What is the p-value: | ||||||||||
| What is your decision: REJ or NOT reject the null? | ||||||||||
| Why? | ||||||||||
| What is your conclusion about the factors influencing the population salary values? | ||||||||||
| c. | If we rejected the null hypothesis, we need to test the significance of each of the variable coefficients. | |||||||||
| Step 1: State the appropriate coefficient hypothesis statements: | (Write a single pair, we will use it for each variable separately.) | |||||||||
| Ho: | ||||||||||
| Ha: | ||||||||||
| Step 2: | Significance (Alpha): | |||||||||
| Step 3: | Test Statistic and test: | |||||||||
| Why this test? | ||||||||||
| Step 4: | Decision rule: | |||||||||
| Step 5: | Conduct the test | |||||||||
| Note, in this case the test has been performed and is part of the Regression output above. | ||||||||||
| Step 6: | Conclusion and Interpretation | |||||||||
| Place the t and p-values in the following table | ||||||||||
| Identify your decision on rejecting the null for each variable. If you reject the null, place the coefficient in the table. | ||||||||||
| Midpoint | Age | Perf. Rat. | Seniority | Raise | Gender | Degree | ||||
| t-value: | ||||||||||
| P-value: | ||||||||||
| Rejection Decision: | ||||||||||
| If Null is rejected, what is the variable's coefficient value? | ||||||||||
| Using the intercept coefficient and only the significant variables, what is the equation? | ||||||||||
| Salary = | ||||||||||
| d. | Is gender a significant factor in salary? | |||||||||
| e. | Regardless of statistical significance, who gets paid more with all other things being equal? | |||||||||
| f. | How do we know? | |||||||||
| 3 | After considering the compa-ratio based results in the lectures and your salary based results, what else would you like to know | |||||||||
| before answering our question on equal pay? Why? | ||||||||||
| 4 | Between the lecture results and your results, what is your answer to the question | |||||||||
| of equal pay for equal work for males and females? Why? | ||||||||||
| Your findings: | ||||||||||
| The lecture's related findings: | ||||||||||
| Overall conclusion: | ||||||||||
| 5 | What does regression analysis show us about analyzing complex measures? | |||||||||