Week 7

Question 1

What is categorical data?

Answer 1

Ordinal (e.g. 1st 2nd 3rd)

Nominal (e.g. Olympic sponsors)

2 categories - dichotomous and binary

Question 2

what does the chi squared test compare?

Answer 2

Observed frequencies in our sample with the frequencies we would expect if there were no relationship at all between the two variables

Question 3

What are the assumptions for the chi squared (x2) test?

Answer 3

Randomly sampled
Independent measures
Counts not percentages
Calculated expected values should be no less than 1
No more than 20% of expected values should be less than 5
Variables must be categorical
Measures must be independent

Question 4

What is the McNemar test?

Answer 4

Paired equivalent to M-D X2 test

If we had a repeated measures design with two dichotomous variables we would use this test

Used to test for differences where samples are paired

DV and IV must be dichotomous (only 2 categories each)