Correspondence Analysis

Correspondence analysis is a procedure for exploring the relationships among two or more sets of variables. A key feature of the analysis is the joint scaling of both row and column variables to provide information on the interrelationships among variables within a set (either row or column variables) and in interrelationships between row and column variables. Correspondence analysis can be used on qualitative or quantitative data. A final step in the analysis involves rescaling of characteristic vectors into optimal scores. Normalizing these optimal scores allows for assessment of relative importance of factors. Correspondence analysis can also be used to find the optimal ordering of variables for a given set of characteristics. If the technique is extended to three or more sets of variables, it is called multiple correspondence analysis.