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Flashcards in Categorical data 1 Deck (12)
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1

When carrying out tests for proportions what makes them valid in a one sample test?

when r>5 and (n-r)>5 where r is the number in the sample with the characteristic of interest

2

In a two-sample test of proportion what is necessary to make it valid?

r1, R2, (n1-r1) and (n2-r2) are all >5

3

What is the simplest approach of carrying out a test of association?

Chi-squared test

4

What is the Chi-squared test?

X2 = sigma (obs-exp)2/exp

5

What are the assumptions for a Chi-squared test?

observations are from independent subjects or experimental units
The expected values are not too small as a rough rule, no more than 20% of the expected values should be <5 and none should be <1

6

What test should be used instead of a Chi-squared test if the variables are ordered?

Chi square test for trend (trend needs to be linear to be appropriate)

7

In the case of a 2X2 table, what test should be carried out when the values of interest are very small?

Chi squared test with continuity correction (conservative) or Fisher's exact test

8

What tests can be used for comparisons of proportions from paired samples?

Paired confidence interval
McNemar's test

9

What test should be used for 1 variable with 2 categories?

1 proportion CI and test

10

What test should be used in a 2x2 table?

2 proportion CI and test
Chi-squared test of association
Chi-squared test of association with continuity correction
Fishers exact test

11

What test should be used in >2x>2 table

Chi-squared test of association
Chi-squared test for trend( if categories ordered)
or collapse rows and/or columns to 2x2

12

What test should be used for paired data?

McNemars or CI for paired data