Parametric tests

Question 1

What are parametric tests?

Answer 1

Tests that have certain rules, or parameters, about when they can be used

Question 2

What are the good things about parametric tests?

Answer 2

They’re more powerful and robust than other tests
They are more sensitive to the features of the data collected and may detect significance within some data sets that non-parametric tests cannot

Question 3

What are the parametric tests?

Answer 3

Unrelated T-test, related T-test and Pearsons r

Question 4

What are the 3 criteria for a parametric test?

Answer 4

• Data must be interval level
• The data should be drawn from a population which would be expected to show a normal distribution for the variable being measured
• There should be homogeneity of variance

Question 5

How can we check for a normal distribution of a variable in a population?

Answer 5

If the mean, median and mode values are similar

Question 6

What is homogeneity of variance?

Answer 6

Sets of scores in each condition should have a similar dispersion or spread

Question 7

How can we determine homogeneity of variance?

Answer 7

Comparing the standard deviation in each condition; if they’re similar a parametric test may be used
OR carrying out an F-test

Question 8

What is an F-test?

Answer 8

It tests for a difference in variance between the two sets of data