R: Predict method for 'brmultinom' fits

predict.brmultinom {brglm2} | R Documentation

## Predict method for `brmultinom` fits

### Description

Obtain class and probability predictions from a fitted baseline category logits model.

### Usage

    ## S3 method for class 'brmultinom'
    predict(object, newdata, type = c("class", "probs"), ...)

### Arguments

`object` | a fitted object of class inheriting from `"brmultinom"`.
`newdata` | optionally, a data frame in which to look for variables with which to predict. If omitted, the fitted linear predictors are used.
`type` | the type of prediction required. The default is `"class"`, which produces predictions of the response category at the covariate values supplied in `"newdata"`, selecting the category with the largest probability; the alternative `"probs"` returns all category probabilities at the covariate values supplied in `"newdata"`.
`...` | further arguments passed to or from other methods.

### Details

If `newdata` is omitted the predictions are based on the data used for the fit.

### Value

If `type = "class"` a vector with the predicted response categories; if `type = "probs"` a matrix of probabilities for all response categories at `newdata`.

### Examples

    data("housing", package = "MASS")

    # Maximum likelihood using brmultinom with baseline category 'Low'
    houseML1 <- brmultinom(Sat ~ Infl + Type + Cont, weights = Freq,
                           data = housing, type = "ML", ref = 1)

    # New data
    newdata <- expand.grid(Infl = c("Low", "Medium"),
                           Type = c("Tower", "Atrium", "Terrace"),
                           Cont = c("Low", NA, "High"))

    ## Predictions
    sapply(c("class", "probs"), function(what) predict(houseML1, newdata, what))

[Package brglm2 version 0.6.2 Index]