Homework Assignments:

Please note **REVISIONS** for Homework 6. Extra ANOVA problems have been added, and Estimation problems deleted.

Except for the first week, homeworks are all due Wednesday at the *beginning* of class. You will have a chance in labs to work on computer homework. Late homework receives half credit; quarter credit if more than one week overdue.

NOTE: Printouts from SPSS must be *annotated* to receive full credit. Circle the most important numbers and explain (write directly on the printout) what they mean. Assume your audience understands basic statistics but is unfamiliar with SPSS. You must demonstrate that you are able to read and understand what you have produced. For problems completed by hand, be sure to show all steps. Book has answers to odd-numbered problems. Homeworks 1-4 worth 5 points each; 5-8 worth 7 points each.

Homework 1: Concepts, Scaling, Frequency Tables and Histograms

G&W Ch 1 (p. 29): problems 4, 5 & 10, & 18; Ch 2, problem 4. You may do problem 4 either using SPSS or by hand. Do not group. [TIP: if SPSS is "grouping" when you don't want it to, click Bar Graph instead of Histogram.] If you use SPSS for problem 4, be sure to include the printout, clearly identify which parts of the printout go with the homework question, and don't forget part c of the question.

Points: Ch 1, #4&5, 2 each, #10 & 18, 1 each, Ch2, #4, 2 pts.

Homework 2: Central Tendency & Variability

G&W Ch 3, problem 12. Ch 4, problems 4 & 16 [by hand] & 17 [with variations as described below] *Do 16 (showing all steps) using the definitional formula, then using the computational formula (p. 96). Explain any differences in the results. For 17, use SPSS to find the mean, sample variance, and standard deviation for the data (step 1). Then (part 2) change the numbers around until you have a data set that has the SAME mean and n, but twice the sample variance as the original data set. Hand in the SPSS printout showing the mean, variance, & sd for both data sets, annotate to clarify which parts of the printout go with parts 1 & 2, and write down the numbers in the data set you created for part 2.

Points: Ch 3, #12: 1 , Ch 4, #4: ¢, #16: 1 ¢, #17: 2 pts.

Homework 3: z-Scores

G&W Ch 5, problems 2, 4, 6, *14* For question 14, explain your answer. SPSS homework: Using the data set given on p. 27 SG, calculate each student's IQ z-scores using 100 as Á and 15 as . Appendix B, SG shows how to create a new variable using formulas. Print out resulting data set and hand in as part of your homework.

Points: Each problem worth 1 point.

Sample Means, z-Test

G&W Ch 6, problems 8ab & 13ab. Ch 7, problems 1,2, 22. Ch 8, problem 11. *For problem 11, go step by step (see G&W 199-200 for the steps), and show all work.* NO SPSS homework this week.

Points: Ch 6 problems & Ch 7, #1&2 worth ¢ each, #22 worth 1. Ch 8, #11 worth 2 points.

Homework 5: t-Tests with Independent Samples and Related Samples

G&W Ch 10, problems 2,3, & 22. Do 22 both by hand (following G&W step-by-step method, p. 247) and on SPSS. Annotate printout by circling the key elements in the output and explaining what the output shows. Ch 11, problems 1, 4, & 18 [including extra SPSS exercise]. Do 18 both by hand (following G&W step-by-step method, p. 269) and on SPSS. Extra exercise: Reenter the data as though this were an independent measures design, with 7 subjects measured before and 7 DIFFERENT subjects measured after sensory deprivation. Hand in annotated SPSS printouts for both the original and reentered data (identify which is which). Also EXPLAIN on the printout why the tests came out differently.

Points: Ch 10 #2&3, Ch 11 #1&4, ¢ point each. Ch 10 #22, 2 pts. Ch 11 #18, 3 pts.

Homework 6 (REVISED): One-way ANOVA

G&W, Ch 13, problems 1,2,5,6,16,17 & 22. Do problems 16 & 17 "by hand." Do the ANOVA for 22 both by hand and using SPSS (note: treat the personality types as a fixed effect). For by hand version of 22, follow and show all steps given in G&W pp. 329-332, and also *create an ANOVA summary table* (see top of page 333). Annotate output thoroughly--circle all relevant info and make notes, summarize the results in English, and give results in APA form.

Points: Ch 13, #1,2,5&6, ¢ pt each. #16, 17, 1 pt each; #22, 3 pts.

Homework 7: Factorial ANOVA, Correlation

G&W Ch 14, problems 2,3, & 20. Do #20 using SPSS (no need to do this by hand!) For problem #20, be sure to request means (under options) for help in interpreting the interaction. Ch 15, problems 2 (by hand, using definitional formula), 10, 12 (using SPSS). For problem 12, after doing the calculations for both Pearson & Spearman for the data set given, try to substantially reduce both correlations by adding a single person (make up the LCU and visits data for this person). Hand in annotated printouts for both original and modified data sets (identify which is which). Explain on the modified printout what you learned from the exercise about the possible impact of a single case on correlation.

Points: Ch 15, #10, ¢ pt. Ch 14, #2, 3, 20, 1 pt each. Ch 14, #2, 2 pts. Ch 15, #12, 1.5 pts.

Homework 8: Regression, Chi-Square

G&W Ch 15, problem 20, by hand. Ch 16, problems 5, 6, & 16. Do all chi-square problems by hand (do not use SPSS).

Points: Ch 15, #20, 1 pt. Ch 16 problems: 2 pts each.