Employee True Score Test 1 (max=100) Test 2 (max=30) Performance (max=5)

Beatrice Hein 87 83 19 5

Teri Rainboth 95 97 30 5

Robert Holton 72 80 25 4

Lonny Voss 73 75 22 3

Gail Jarman 84 80 28 4

1. Calculate the mean of the errors associated with Test 1. Do your calculations by hand and show your work (i.e., show me the formula and what you have plugged in at each step to derive your answer). Then enter the data in Excel and create the output that verifies your calculations (attach the output to this assignment): (0.75 pt)

True Score = Actual Score + Error, therefore Error = True Score Actual Score

2. Calculate the standard deviation of the errors associated with Test 1. Do your calculations by hand and show your work (i.e., show me the formula and what you have plugged in at each step to derive your answer). Then generate the answers using Excel and attach the output that verifies your calculations: (0.75 pt)

Standard deviation of error = Square root[(error mean error) ² / (n-1)]

3. Use Excel to calculate the alternate forms reliability of Test 1 as measured by its association with scores on Test 2 Attach your output. (0.75 pt)

4. Estimate the standard error of the measurement associated with test 1 using the reliability estimated in 3. above. Why doesnt the estimate here equal the standard deviation of the errors calculated in 2. above? (1.5 pts)

5. Assume that a new job candidate scores 87 on Test 1. Using the standard error of measurement estimated in Question 3 above, identify the 95% confidence interval within which her true score is likely to lie. (1.5 pts)

6. Assume that a new job candidate scores 87 on Test 1. Using the standard error of measurement estimated in Question 3 above, identify the 99% confidence interval within which her true score is likely to lie. (0.75 pt)

7. What is the probability that his true score is greater than 96? (0.75 pt)

8. Looking at the Test 1 scores, are there any candidates that you can confidently conclude are either more, or less qualified than the others (using a 95% confidence interval)? (0.75 pt)

9. If the scale for Test 2 is changed so that it is measured on a scale from 0 to 100 like Test 1, what impact would this have on the estimated alternate forms reliability? (0.5 pt)

10. Using Excel, what is the criterion-related validity associated with Test 1? Attach your output here. (0.75 pt)