Predicts positions of new documents using a fitted Wordfish model
# S3 method for wordfish predict( object, newdata = NULL, se.fit = FALSE, interval = c("none", "confidence"), level = 0.95, ... )
| object | A fitted wordfish model |
|---|---|
| newdata | An optional data frame or object of class wfm in which to look for word counts to predict document ideal points which to predict. If omitted, the fitted values are used. |
| se.fit | A switch indicating if standard errors are required. |
| interval | Type of interval calculation |
| level | Tolerance/confidence level |
| ... | further arguments passed to or from other methods. |
predict.wordfish produces a vector of predictions or a matrix
of predictions and bounds with column names `fit' and `se.fit', and with
`lwr', and `upr' if `interval' is also set.
Standard errors for document positions are generated by numerically inverting the relevant Hessians from the profile likelihood of the multinomial form of the model.
Will Lowe