margins for polr estimators

[maximeto]

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• a possible bug
• a question about package functionality
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I can't understand the type of prediction the margins function uses for the polr estimator.
Typical polr prediction would be a vector of predicted probabilities. The margin function only returns one statistic.
Which one is that?

Thanks!

## load package
library("margins")
library(polr)

house.plr <- polr(Sat ~ Infl + Type + Cont, weights = Freq, data = housing)
predict(house.plr, type = 'p')
margins(house.plr, type = 'p')