BUS 308 - Statistics Wk 4 Problem set
Data
| ID | Sal | Compa | Mid | Age | EES | SER | G | Raise | Deg | Gen1 | Gr | ||||||
| 1 | 58 | 1.017 | 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 | 27 | 0.870 | 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 | 1.096 | 31 | 30 | 75 | 5 | 1 | 3.6 | 1 | F | B | ||||||
| 4 | 66 | 1.157 | 57 | 42 | 100 | 16 | 0 | 5.5 | 1 | M | E | The column labels in the table mean: | |||||
| 5 | 47 | 0.979 | 48 | 36 | 90 | 16 | 0 | 5.7 | 1 | M | D | ID – Employee sample number | Sal – Salary in thousands | ||||
| 6 | 76 | 1.134 | 67 | 36 | 70 | 12 | 0 | 4.5 | 1 | M | F | Age – Age in years | EES – Appraisal rating (Employee evaluation score) | ||||
| 7 | 41 | 1.025 | 40 | 32 | 100 | 8 | 1 | 5.7 | 1 | F | C | SER – Years of service | G – Gender (0 = male, 1 = female) | ||||
| 8 | 23 | 1.000 | 23 | 32 | 90 | 9 | 1 | 5.8 | 1 | F | A | Mid – salary grade midpoint | Raise – percent of last raise | ||||
| 9 | 77 | 1.149 | 67 | 49 | 100 | 10 | 0 | 4 | 1 | M | F | Grade – job/pay grade | Deg (0= BS\BA 1 = MS) | ||||
| 10 | 22 | 0.956 | 23 | 30 | 80 | 7 | 1 | 4.7 | 1 | F | A | Gen1 (Male or Female) | Compa - salary divided by midpoint, a measure of salary that removes the impact of grade | ||||
| 11 | 23 | 1.000 | 23 | 41 | 100 | 19 | 1 | 4.8 | 1 | F | A | ||||||
| 12 | 60 | 1.052 | 57 | 52 | 95 | 22 | 0 | 4.5 | 0 | M | E | This data should be treated as a sample of employees taken from a company that has about 1,000 | |||||
| 13 | 42 | 1.050 | 40 | 30 | 100 | 2 | 1 | 4.7 | 0 | F | C | employees using a random sampling approach. | |||||
| 14 | 24 | 1.043 | 23 | 32 | 90 | 12 | 1 | 6 | 1 | F | A | ||||||
| 15 | 24 | 1.043 | 23 | 32 | 80 | 8 | 1 | 4.9 | 1 | F | A | ||||||
| 16 | 47 | 1.175 | 40 | 44 | 90 | 4 | 0 | 5.7 | 0 | M | C | Mac Users: The homework in this course assumes students have Windows Excel, and | |||||
| 17 | 69 | 1.210 | 57 | 27 | 55 | 3 | 1 | 3 | 1 | F | E | can load the Analysis ToolPak into their version of Excel. | |||||
| 18 | 36 | 1.161 | 31 | 31 | 80 | 11 | 1 | 5.6 | 0 | F | B | The analysis tool pak has been removed from Excel for Windows, but a free third-party | |||||
| 19 | 24 | 1.043 | 23 | 32 | 85 | 1 | 0 | 4.6 | 1 | M | A | tool that can be used (found on an answers Microsoft site) is: | |||||
| 20 | 34 | 1.096 | 31 | 44 | 70 | 16 | 1 | 4.8 | 0 | F | B | http://www.analystsoft.com/en/products/statplusmacle | |||||
| 21 | 76 | 1.134 | 67 | 43 | 95 | 13 | 0 | 6.3 | 1 | M | F | Like the Microsoft site, I make cannot guarantee the program, but do know that | |||||
| 22 | 57 | 1.187 | 48 | 48 | 65 | 6 | 1 | 3.8 | 1 | F | D | Statplus is a respected statistical package. | You may use other approaches or tools | ||||
| 23 | 23 | 1.000 | 23 | 36 | 65 | 6 | 1 | 3.3 | 0 | F | A | as desired to complete the assignments. | |||||
| 24 | 50 | 1.041 | 48 | 30 | 75 | 9 | 1 | 3.8 | 0 | F | D | ||||||
| 25 | 24 | 1.043 | 23 | 41 | 70 | 4 | 0 | 4 | 0 | M | A | ||||||
| 26 | 24 | 1.043 | 23 | 22 | 95 | 2 | 1 | 6.2 | 0 | F | A | ||||||
| 27 | 40 | 1.000 | 40 | 35 | 80 | 7 | 0 | 3.9 | 1 | M | C | ||||||
| 28 | 75 | 1.119 | 67 | 44 | 95 | 9 | 1 | 4.4 | 0 | F | F | ||||||
| 29 | 72 | 1.074 | 67 | 52 | 95 | 5 | 0 | 5.4 | 0 | M | F | ||||||
| 30 | 49 | 1.020 | 48 | 45 | 90 | 18 | 0 | 4.3 | 0 | M | D | ||||||
| 31 | 24 | 1.043 | 23 | 29 | 60 | 4 | 1 | 3.9 | 1 | F | A | ||||||
| 32 | 28 | 0.903 | 31 | 25 | 95 | 4 | 0 | 5.6 | 0 | M | B | ||||||
| 33 | 64 | 1.122 | 57 | 35 | 90 | 9 | 0 | 5.5 | 1 | M | E | ||||||
| 34 | 28 | 0.903 | 31 | 26 | 80 | 2 | 0 | 4.9 | 1 | M | B | ||||||
| 35 | 24 | 1.043 | 23 | 23 | 90 | 4 | 1 | 5.3 | 0 | F | A | ||||||
| 36 | 23 | 1.000 | 23 | 27 | 75 | 3 | 1 | 4.3 | 0 | F | A | ||||||
| 37 | 22 | 0.956 | 23 | 22 | 95 | 2 | 1 | 6.2 | 0 | F | A | ||||||
| 38 | 56 | 0.982 | 57 | 45 | 95 | 11 | 0 | 4.5 | 0 | M | E | ||||||
| 39 | 35 | 1.129 | 31 | 27 | 90 | 6 | 1 | 5.5 | 0 | F | B | ||||||
| 40 | 25 | 1.086 | 23 | 24 | 90 | 2 | 0 | 6.3 | 0 | M | A | ||||||
| 41 | 43 | 1.075 | 40 | 25 | 80 | 5 | 0 | 4.3 | 0 | M | C | ||||||
| 42 | 24 | 1.043 | 23 | 32 | 100 | 8 | 1 | 5.7 | 1 | F | A | ||||||
| 43 | 77 | 1.149 | 67 | 42 | 95 | 20 | 1 | 5.5 | 0 | F | F | ||||||
| 44 | 60 | 1.052 | 57 | 45 | 90 | 16 | 0 | 5.2 | 1 | M | E | ||||||
| 45 | 55 | 1.145 | 48 | 36 | 95 | 8 | 1 | 5.2 | 1 | F | D | ||||||
| 46 | 65 | 1.140 | 57 | 39 | 75 | 20 | 0 | 3.9 | 1 | M | E | ||||||
| 47 | 62 | 1.087 | 57 | 37 | 95 | 5 | 0 | 5.5 | 1 | M | E | ||||||
| 48 | 65 | 1.140 | 57 | 34 | 90 | 11 | 1 | 5.3 | 1 | F | E | ||||||
| 49 | 60 | 1.052 | 57 | 41 | 95 | 21 | 0 | 6.6 | 0 | M | E | ||||||
| 50 | 66 | 1.157 | 57 | 38 | 80 | 12 | 0 | 4.6 | 0 | M | E |
Week 4
| Week 4 | Confidence Intervals and Chi Square (Chs 11 - 12) | Let's look at some other factors that might influence pay. | Q1 | Q2 | <Note: use right click on row numbers to insert rows to perform analysis below any question> | |||||||||||||||||||
| For question 3 below, be sure to list the null and alternate hypothesis statements. Use .05 for your significance level in making your decisions. | Gr | Deg | Gen1 | Sal | ||||||||||||||||||||
| For full credit, you need to also show the statistical outcomes - either the Excel test result or the calculations you performed. | A | 0 | F | 34 | ||||||||||||||||||||
| 1 | One question we might have is if the distribution of graduate and undergraduate degrees independent of the grade the employee? | A | 0 | F | 41 | |||||||||||||||||||
| (Note: this is the same as asking if the degrees are distributed the same way.) | ||||||||||||||||||||||||
| Based on the analysis of our sample data (shown below), what is your answer? | ||||||||||||||||||||||||
| Ho: The populaton correlation between grade and degree is 0. | C | 0 | F | 77 | ||||||||||||||||||||
| Ha: The population correlation between grade and degree is > 0 | ||||||||||||||||||||||||
| Perform analysis: | ||||||||||||||||||||||||
| OBSERVED | A | B | C | D | E | F | Total | |||||||||||||||||
| COUNT - M or 0 | 7 | 5 | 3 | 2 | 5 | 3 | 25 | |||||||||||||||||
| COUNT - F or 1 | 8 | 2 | 2 | 3 | 7 | 3 | 25 | |||||||||||||||||
| total | 15 | 7 | 5 | 5 | 12 | 6 | 50 | |||||||||||||||||
| EXPECTED | ||||||||||||||||||||||||
| 7.5 | 3.5 | 2.5 | 2.5 | 6 | 3 | 25 | <Highlighting each cell with show how the value | |||||||||||||||||
| 7.5 | 3.5 | 2.5 | 2.5 | 6 | 3 | 25 | is found: row total times column total divided by | |||||||||||||||||
| 15 | 7 | 5 | 5 | 12 | 6 | 50 | grand total.> | |||||||||||||||||
| By using either the Excel Chi Square functions or calculating the results directly as the text shows, do we | ||||||||||||||||||||||||
| reject or not reject the null hypothesis? What does your conclusion mean? | ||||||||||||||||||||||||
| Interpretation: | ||||||||||||||||||||||||
| 2 | Using our sample data, we can construct a 95% confidence interval for the population's mean salary for each gender. | |||||||||||||||||||||||
| Interpret the results. How do they compare with the findings in the week 2 one sample t-test outcomes (Question 1)? | ||||||||||||||||||||||||
| Males | Mean | St error | Low | to | High | |||||||||||||||||||
| 52 | 3.6587793957 | 44.4482793272 | 59.5517206728 | Results are mean +/-2.064*standard error | ||||||||||||||||||||
| Females | 38 | 3.6227541769 | 30.5226353789 | 45.4773646211 | 2.064 is t value for 95% interval | |||||||||||||||||||
| <Reminder: standard error is the sample standard deviation divided by the square root of the sample size.> | ||||||||||||||||||||||||
| Interpretation: | ||||||||||||||||||||||||
| C | 0 | F | 55 | |||||||||||||||||||||
| D | 1 | M | 77 | |||||||||||||||||||||
| 3 | Based on our sample data, can we conclude that males and females are distributed across grades in a similar pattern within the population? | D | 1 | M | 60 | |||||||||||||||||||
| 4 | Using our sample data, construct a 95% confidence interval for the population's mean service difference for each gender. | |||||||||||||||||||||||
| Do they intersect or overlap? How do these results compare to the findings in week 2, question 2? | ||||||||||||||||||||||||
| 5 | How do you interpret these results in light of our question about equal pay for equal work? | |||||||||||||||||||||||