The aims of this paper include the identification of predictors of death risk and the examination of interaction effects between them. In this study, a logistic regression model is used to estimate death probability at old age (above 60) in the Pomorskie Voivodship in 2009. The following risk factors of death are considered: age, gender and place of residence (urban/rural areas). In the model, age is treated both as a continuous variable and as a categorical variable. The paper presents an analysis of interaction effects between predictors with the use of product terms in the logistic regression model. The emphasis is on the interpretation of the coefficients of the interactive logistic model. The study includes cases of interactions between qualitative predictors, between qualitative and quantitative predictors, and between quantitative predictors. It appears that the interaction between gender and age is statistically significant.
logistic regression, interaction effect, death probability
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