7 Independent T-Tests
This activity introduces the independent t-test – a powerful test to use when you are comparing two groups or conditions. There are two variants of the t-test:
paired samples t-tests.
The independent t-test is used when you have two groups of individuals or cases. For example:
male versus female;
experimental versus control group.
Data files are set up differently according to which t-test is chosen. In addition there are separate menus in SPSS for each type of t-test. Finally, each t-test will produce different outputs.
The data file used in this activity is based on a study by Montello, Lovelace, Golledge and Self (1999). It looks at gender differences in spatial abilities, including map reading.
The experimental hypothesis for this study would be that:
There is a difference between males and females in spatial reading ability with males performing better in spatial tasks than females.
Remember that for an independent t-test the data file should have at least two columns – one for the independent variable and one for the dependent variable.