Lesson 6

Question 1

What do all t-tests have in common?

Answer 1

They all involve 2 groups.

Question 2

What is the limitation of z scores?

Answer 2

Are only fine if you have a large enough sample.

Question 3

What are the 3 pieces of data you need when doing a t-test?

Answer 3

• the difference between the means of 2 groups.
• the SD of each group.
• the sample size of each group.

Question 4

Can I do a t-test comparing the days it rained in April vs September?

Answer 4

No, because those are discrete not continuous variables.

Question 5

What is something we assume when conducting the t-test?

Answer 5

• the DV is normally distributed for each group

- Each group have similar SD.

Question 6

What is the distinction between the different t-tests?

Answer 6

One -sample: comparing sample to population
Independent- two different samples.
Dependent- same sample measured at different times .

Question 7

How do you calculate the degrees of freedom?

Answer 7

The number of participants -1.

Question 8

What numbers correspond with what effect size?

Answer 8

0. 2 - small/weak effect size
1. 5 - medium
2. 8 - large effect size /ps