Unformatted text preview: e values your independent level can take Null, Main, Interaction Terminology Dependent variable What you presume is being affected by your independent variable Also called effect or outcome variable Example... If you have an educational program you are testing for impact on academic achievement with various measures DV = Measures of academic achievement IV = Educational program What statistic do you use Question #1 how many independent variables do you have? Question #2 are your independent variables quantitative or categorical? Question #3 are you measuring the same subjects at different time points or not? If you can answer these questions, then you know which stats to use Ttests, ANOVA, and Review TTest Dependent variable is continuous ONE independent variable that is categorical Example: twogroup posttest only design Examine effect of ritalin and behavioral modification in ADHD Two groups: Exp = gets ritalin+behavioral mod, control=gets ritalin only Examine whether two groups are different on ADHD ADHD Score 80 75 70 65 60 55 50 45 40 35 30 Pretest Posttest r+behmod r only Where can we find differences? Group 1 and group 2 at pretest? Group 1 and group 2 at posttest? Change in group 1 from pretest to postest? Change in group 2 from pretest to postest?
80 75 70 65 60 55 50 45 40 35 30 Pretest Posttest r+behmod r only 1. 2. 3. 4. If the program is effective we want...
No group differences at pretest No change in control group from pre- post Group dif...
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- Spring '07
- Statistics, Statistical hypothesis testing, control program, Student's t-test, independent samples t-tests