1. set up a hypothesis for the following variables: a) married/cohabiting, b) current smokers, c) GHQ depression

2. calculate test statistics for Q1 (report differences, z-value, and p-values, keep 4 decimal points).

3. if redo a comparison study, try to examine the difference between the two groups (no dementia vs. dementia) in GHQ depression, you are asked to calculate a) effect size, b) sample size for each group @ α=0.05 and β=0.2.

Table 1 Characteristics of the study population at age 50. N Women Ethnicity, Nmon-white- Less than secondary school diploma Married/cohabiting Moderate alcohol drinking (1-14 units per week) Current smokers Moderate-to-vigorous physical activity (h), M (SD) BMI 30 kg/m Diabetes Hypertension Cardiovascular disease GHQ depression CNS medications Mental disorders before age 65 Dementia status at end of follow-up Dementia P 521 219 (42.0) 79 (15.2) No dementia 7438 2390 (321) 719 (9.7) 3509 (47.2) 5647 (75.9) 4082 (54.9) 1138 (15.3) 3.3 (3.7) 823 (11.1) 182 (2.5) 1700 (22.9) 214 (2.9) 1070 (14.4) 322 (4.3) 541 (7.3) 310 (59.5) 369 (70.8) 273 (52.4) 101 (19.4) 3.3 (3.7) 66 (12.7) 17 (3.3) 150 (28.8) 10 (1.9) 89 (17.1) 36 (6.9) 42 (8.1)