Learning Check, T-tests

1. A research article reports results of a study using a __t __test for
dependent means as "__t(__16) = 2.67, __p __< .05." This means

a. the results were inconclusive.

b. there were 16 subjects.

c. the __t __score was 16.

d. the __t __score was 2.67.

2. Testing subjects before and after an experimental manipulation is
called a __________ design.

3. A research article reports results of a study using a __t __test for
dependent means as "__t(__38) = 3.11, __p __< .01." This means

a. the result is significant.

b. the result is not significant.

c. a one-tailed test was used.

d. the critical value for .01 alpha was 3.11.

4. Which equations have the following structure:

A deviation from a mean divided by a standard deviation?

Answers below

Answers, LC T-tests

1. d

2. repeated-measures, OR within-subjects, OR pretest-posttest

3. a

4. equation for Z-score: X - M / SD

hypothesis-test when pop variance known:

Z= X-bar - Mu / SE-means

t-test for single sample (Mu known)

t(df)= X-bar - Mu / S_{M} [est SE]

t-test for dependent means

t(df)= X-bar(diff) - Mu(diff) / S_{M }(mean diff)