Relations in Categorical Data

Contingency Tables (Two-way) Ticket class and survival statistics from the Titanic

Two-way Table This allows us to look at two categorical variables together Each cell of the table gives us counts for the combination of the two given variables.

Variables Row variable – the variable distributed in the rows of the two-way table. In this example: Survival Column variable - the variable distributed in the columns of a two-way table. In this example: Class

Marginal Distribution The margins, both on the right and on the bottom, give totals for each variable. This is the marginal distribution for Class

Conditional Distributions A conditional distribution shows the distribution of one variable for just the individuals who satisfy some condition on another variable. The following is the conditional distribution of ticket Class, conditional on having survived:

Conditional Distributions (cont.) The following is the conditional distribution of ticket Class, conditional on having perished: