Generalised linear models: logistic and probit regression for a binary outcome (yes/no, success/failure, event/no-event), and Poisson regression for a count outcome (number of events, visits, occurrences).
Note
Examples
Logistic, single and two-group
- Simple logistic regression: one continuous predictor
relapse ~ biomarker_level— one continuous predictor on a yes/no outcome, no covariates. - Logistic two-group comparison (binary predictor)
remission ~ treatment— compare event rates between two groups (chi-square recast).
Logistic, adjusted and categorical
- Logistic regression with a categorical predictor
survived ~ habitat— a multi-level categorical predictor on a binary outcome. - Multiple logistic regression: covariate-adjusted
employed ~ years_education + age + gender— a focal predictor on a binary outcome, covariate-adjusted. - Logistic regression: continuous predictor plus categorical control
employed ~ experience_years + region— a continuous predictor plus a categorical control (parallel slopes).
Logistic interactions
- Logistic continuous-by-continuous moderation
relapse ~ biomarker_level * age— do two continuous predictors interact on a binary outcome? - Logistic treatment-by-moderator interaction (binary x continuous)
remission ~ treatment * biomarker_level— a binary-by-continuous interaction on a yes/no outcome. - Logistic 2x2 factor-by-factor interaction
voted ~ gender * urban— two binary factors interacting on a binary outcome. - Logistic three-way interaction
germinated ~ light * moisture * temperature— a three-way interaction on a binary outcome.
Count and probit outcomes
- Poisson count regression: clinic visits predicted by treatment and age
clinic_visits ~ treatment + age— a count outcome, log-link Poisson regression with a binary and a continuous predictor. - Probit regression: household income predicting voter turnout, controlling for region
voted ~ income + region— a binary outcome via the probit link, one continuous predictor plus a categorical control.