7. Chi-square

Question 1

What type of data does chi-square used? (Methods1 chi-square)

Answer 1

Nominal or categorical data

Question 2

What does the goodness of fit test do? (Methods1 chi-square)

Answer 2

Compares an observed frequency distribution with an expected frequency distribution

Question 3

What is the equation for the expected frequency? (Methods1 chi-square)

Answer 3

EF = total number of observations / number of categories

Question 4

What are the two types of chi-square tests? (Methods1 chi-square)

Answer 4

• Goodness of fit test

- Association test

Question 5

What is the chi-square association test based on? (Methods1 chi-square)

Answer 5

The association between two independent variables

Question 6

What are the two assumptions of chi-square? (Methods1 chi-square)

Answer 6

1) observations must be independent

2) problems occur when expected frequencies are small

Question 7

If the expected frequency value is less that 5, what would you use to make the test more conservative? (Methods1 chi-square)

Answer 7

Yates correction for continuity

Question 8

How do you work out Yates correction for continuity? (Methods1 chi-square)

Answer 8

1) Take the absolute value for O-E (ignoring any minus signs)
2) Subtract 0.5 from the O-E before squaring it