Chapter 7

Question 1

Cohen’s d

Answer 1

a standardized measure of effect used to measure the difference between means.

Question 2

critical value of t

Answer 2

value of t used to determine whether a null hypothesis is rejected or not; abbreviated tcv.

Question 3

degrees of freedom (df)

Answer 3

the number of values in a sample that are free to vary.

Question 4

effect size (d)

Answer 4

a measure of the degree of impact of the independent variable on the dependent variable.

Question 5

replicate

Answer 5

to repeat a study, usually introducing some change in procedure to make it better.

Question 6

r squared

Answer 6

an effect size that calculates how much of the variability in the outcome variable is accounted for by the predictor variable.

Question 7

single-sample t test

Answer 7

a statistical test that compares a sample mean to a population mean when the population standard deviation is not known.

Question 8

underpowered

Answer 8

term for a study with a sample size too small for the study to have a reasonable chance to reject the null hypothesis given the size of the effect.