Categorical Data

Question 1

what is x^2 (chi squared)

Answer 1

the test to determine how often observations fall into a particular category based on what we would expect

categorical data

Question 2

how would you calculate chi squared by hand

Answer 2

1 - create a contingency table to record the frequency of each category (mutually exclusive and exhaustive)

2 - calculate the frequencies expected by chance

3 - calculate chi squared test statistic from the observed and expected frequencies

4 - compare it against critical values from a table

Question 3

what is degrees of freedom for chi squared

Answer 3

number of categories -1

Question 4

how do you calculate the expected value for chi squared with multiple IVs

Answer 4

grand total

Question 5

what are degrees of freedom for chi squared with multiple IVs

Answer 5

(rows-1) x (columns-1)

Question 6

how do you do a single Iv chi squared in spss

Answer 6

analyze
non parametric tests
chi squared

Question 7

how do you do a multiple IV chi squared in SPSS

Answer 7

analyze
descriptive statistics
crosstabs
then press statistics on window
check chi squared box

Question 8

what does chi squared assume

Answer 8

random sample

expected frequencies must be at least 1

no more than 20% can have a frequency of less than 5

Question 9

how do you deal with low frequencies in chi squared

Answer 9

put categories together

discard small categories and run test on remaining data

Question 10

what is the binomial test

Answer 10

used for data that can only have two values - eg yes/no heads/tails

compares if the frequency these two occur compiles with an expected ratio

Question 11

how do you do a binomial test in SPSS

Answer 11

analyze
nonparametric tests
binomial test