Effect Displays in<i>R</i>for Multinomial and Proportional-Odds Logit Models: Extensions to the<b>effects</b>Package 论文
摘要
Based on recent work by Fox and Andersen (2006), this paper describes substantial extensions to the <b>effects</b> package for <b>R</b> to construct effect displays for multinomial and proportional-odds logit models. The package previously was limited to linear and generalized linear models. Effect displays are tabular and graphical representations of terms — typically high-order terms — in a statistical model. For polytomous logit models, effect displays depict fitted category probabilities under the model, and can include point-wise confidence envelopes for the effects. The construction of effect displays by functions in the <b>effects</b> package is essentially automatic. The package provides several kinds of displays for polytomous logit models.