# How to read interaction coefficients in logistic regression?

How do i read age:gender1?

Gender1 is male.

Call:
glm(formula = cardio ~ gender + age + gender * age, family = binomial,
data = CVtrain)

Coefficients:
Estimate Std. Error z value Pr(>|z|)
(Intercept)  -1.060e+01  3.328e-01 -31.843  < 2e-16 ***
age           5.164e-02  2.108e-03  24.492  < 2e-16 ***
gender1       4.146e-01  1.758e-01   2.358 0.018379 *
age:gender1  -8.018e-03  3.283e-03  -2.442 0.014597 *

• How would you read them for a linear model?
– Dave
Dec 27, 2022 at 19:21
• Would it be "The effect on the presence of cardio of 1 unit increase in age is exp(-8.018e-03) = 99% more for those that are male as compared to females" ?? By that measure, gender shouldn't be included at all. Dec 27, 2022 at 19:53
• There is no exponential in a linear model. How would you interpret the interaction in a linear model?
– Dave
Dec 27, 2022 at 20:01
• So then that’s the effect on the log-odds, right?
– Dave
Dec 27, 2022 at 21:48
• See here. Dec 27, 2022 at 22:36