Cross tabulation

(Most of the statistical material related to cross-tabulation is covered under Chi-square.)

Cross-tabluation is about taking two variables and tabulating the results of one variable against the other variable. An example would be the cross-tabluation of course performance against mode of study:

 HD D C P NN FT - Internal 10 15 18 33 8 PT Internal 3 4 8 15 10 External 4 3 12 15 6

Each individual would have had a recorded mode of study (the rows of the table) and performance on the course (the columns of the table). For each indivdual, those pairs of values have been entered into the appropriate cell of the table.

What does cross-tabulation tell you?

A cross-tabulation gives you a basic picture of how two variables inter-relate.

It helps you search for patterns of interaction. Obviously, if certain cells contain disproportionately large (or small) numbers of cases, then this suggests that there might be a pattern of interaction.

In the table above, the basic pattern is what you would expect as a teacher but, at a general level, it says that the bulk of students get a P rating independant of mode of study.

What we normally do is to calculate the Chi-square statistic to see if this pattern has any substantial relevance.

To be Completed