The logistic regression analysis

Logistic regression analysis allows one to predict a discrete outcome such as group membership from a set of variables that may be continuous, dichotomous, or a mix. This technic is use when we want to verifiy if many independant variables can predict a dependant dichotomous variable. Unlike multiple regression and discriminant function analysis, the logistic regression does not require a normal distribution of predictors neither equal variance within each group (homogeneity of variances). Different types of logistic regression exist, each one having a statistic procedure and will conduct the elaboration of differents theorical models. In this way, will be approached the direct types, sequential and stepwise. One example of using this technic with SPSS program, will be presented and the analytical procedure of the results will then be detailled, notably concerning the interpretation of the odds ratio.