Sub ID	Gender	Educ	Age	Mem1	Mem2
1	2	1	65.8	108.43	99.63
2	2	0	66.9	107.01	100.30
3	2	0	76.9	97.29	82.30
4	1	0	79.9	85.77	80.56
5	2	0	67.5	93.40	90.27
6	2	0	84.1	102.19	101.34
7	2	0	72.6	98.31	88.20
8	2	1	75.6	112.20	105.71
9	2	0	82.6	109.89	94.76
10	1	0	78.0	104.75	95.03
11	2	0	66.3	102.19	99.37
12	2	0	65.1	93.70	84.29
13	1	1	67.2	101.30	97.49
14	1	0	70.0	106.59	99.37
15	2	1	80.0	84.34	86.44
16	2	0	69.4	99.12	86.93
17	2	0	65.3	107.04	100.36
18	1	1	70.6	94.42	91.44
19	2	0	78.4	112.80	103.91
20	2	1	69.6	93.83	92.43
21	2	1	65.8	102.60	96.34
22	1	0	75.0	81.45	69.25
23	2	0	68.5	103.55	94.07
24	1	1	69.5	93.13	81.43
25	2	1	67.0	114.53	112.87
26	2	0	69.9	108.73	102.84
27	2	1	86.6	95.89	94.90
28	2	1	66.1	80.11	80.88
29	1	0	65.2	92.13	91.85
30	2	0	76.8	111.96	106.24
31	1	0	75.4	106.01	102.08
32	2	1	66.7	113.34	101.89
33	2	0	65.5	110.51	110.02
34	2	1	72.8	102.92	100.72
35	2	1	79.5	100.49	93.43
36	2	0	72.9	108.46	101.21
37	2	1	69.7	115.03	105.08
38	1	1	66.0	102.62	100.30
39	1	1	71.4	100.00	103.97
40	1	1	75.8	110.02	111.17
41	1	1	65.4	85.77	74.28
42	2	1	67.0	97.02	96.76
43	2	1	79.2	108.46	95.26
44	1	1	69.3	101.39	100.42
45	1	1	68.1	83.58	82.74
46	2	0	77.5	107.63	105.91
47	1	1	67.8	99.51	93.98
48	2	1	73.0	104.82	101.21
49	1	1	71.9	107.02	99.62
50	2	0	68.3	114.60	108.18

A longitudinal project was conducted to study the executive and memory functions of elderly residents in a community. The participants were assessed every few years with a set of cognitive tests. Demographic and health information was also collected.

The researchers want to examine the participant demographic information collected from the first testing session. Run a two-tailed t-test with = .05 to answer the following research question:

Are the females and males significantly different in age ("Age")?

A. What type of t-test should be performed to answer this question? What is your rationale?

B. Create the null hypothesis from the research question. (Hint: Consider whether the hypotheses should be directional or non-directional for a two-tailed test.)

C. Run the analysis in SPSS and answer the following questions based on the analysis results.

Paste all the output tables from SPSS for this test. No points will be earned for the rest of the questions in Q1 if the output tables are not pasted or are incomplete.

[Paste SPSS output tables here.]

D. Use the SPSS output to determine the effect size, Cohen's d,and explain what the effect size means in this context. Effect size must show in the SPSS table. Do not round, report all decimals from the table. (Note: It is OK if d is negative. But it needs to be consistent with the sign of t statistic.)

d =

Explanation:

E. Report the ttest result in symbols according to the APA standards, including t statistic with degree of freedom, p value, and effect size d. (Hint: Present all the items in one single line, separated by commas, with the symbols italicized. Report "p < .001" if SPSS output shows the p value to be ".000".)

F. What is your decision about the null hypothesis (reject or fail to reject)? What is your rationale?

G. What is the answer to the research question?