T-Test

Question 1

In general, what are t-tests used for?

Answer 1

Comparing 2 means to see if they are significantly different from each other

Question 2

What are three types of t-tests and when are they used?

Answer 2

independent samples - 2 means on a single DV (between subjects, quasi-independent variable)
dependent paired/matched samples - means of 2paired or dependent samples (within subjects, matched data)
one sample - data is collected from one sample, under one condition, at one time (see if sample mean is different from population mean)

Question 3

What are the assumptions of t-tests?

Answer 3

• observations within each sample must be independent
• the 2 populations must be normal
• the 2 populations must have equal variances

Question 4

What are limitations of t-tests?

Answer 4

• can only compare 2 means

- can only have one IV with 2 categories

Question 5

Independent samples t-test

Answer 5

used when you want to compare 2 means of independent samples on a single DV

• between subjects design
• quasi indepedent variable

Question 6

dependent paired/matched samples t-test

Answer 6

used when you want to compare means of 2-paired or dependent samples

• within subjects designs
• matched data

Question 7

one sample t-test

Answer 7

data is collected from one sample, under one condition, at one time - we want to see if sample mean is different from population mean