Kontingenssitaulu

Kontingenssitaulu, also known as a contingency table or cross-tabulation, is a fundamental tool in statistics and data analysis used to examine the relationship between two or more categorical variables. It displays the frequency distribution of observations across different categories of these variables.

The basic structure of a kontingenssitaulu is a table where the rows represent the categories of one variable and the columns represent the categories of another variable. Each cell within the table contains the count of observations that fall into the specific combination of categories defined by that row and column. For instance, a 2x2 kontingenssitaulu might show the number of people who possess a certain attribute (e.g., yes/no) and also exhibit another characteristic (e.g., yes/no).

Kontingenssitaulut are instrumental in identifying patterns, associations, and potential dependencies between variables. They are the basis for various statistical tests, such as the chi-squared test of independence, which formally assesses whether the observed distribution of frequencies is significantly different from what would be expected if the variables were independent. Understanding the information presented in a kontingenssitaulu is crucial for drawing meaningful conclusions from categorical data.