car (version 3.0-10)

Predict: Model Predictions


Predict is a generic function with, at present, a single method for "lm" objects, Predict.lm, which is a modification of the standard predict.lm method in the stats package, but with an additional vcov. argument for a user-specified covariance matrix for intreval estimation.


Predict(object, ...)

# S3 method for lm Predict(object, newdata, = FALSE, scale = NULL, df = Inf, interval = c("none", "confidence", "prediction"), level = 0.95, type = c("response", "terms"), terms = NULL, na.action = na.pass, pred.var = res.var/weights, weights = 1, vcov., ...)



a model object for which predictions are desired.

newdata,, scale, df, interval, level, type, terms, na.action, pred.var, weights

optional, either a function to compute the coefficient covariance matrix of object (e.g., hccm) or a coefficient covariance matrix (as returned, e.g., by hccm).

arguments to pass down to Predict or predict methods.


See predict and predict.lm.


If there is no appropriate method for Predict, then a predict method is invoked. If there is a specific predict method for the primary class of object but only an inherited Predict method, then the predict method is invoked. Thus an object of class c("glm", "lm") will invoke method predict.glm rather than Predict.lm, but an object of class c("aov", "lm") will invoke Predict.lm rather than predict.lm.


Fox, J. and Weisberg, S. (2019) An R Companion to Applied Regression, Third Edition, Sage.

See Also

predict, predict.lm


mod <- lm(interlocks ~ log(assets), data=Ornstein)
newd <- data.frame(assets=exp(4:12))
(p1 <- predict(mod, newd, interval="prediction"))
p2 <- Predict(mod, newd, interval="prediction", vcov.=vcov)
all.equal(p1, p2) # the same

(predict(mod, newd, se=TRUE))
(p3 <- Predict(mod, newd, se=TRUE, vcov.=hccm)) # larger SEs
p4 <- Predict(mod, newd, se=TRUE, vcov.=hccm(mod, type="hc3"))
all.equal(p3, p4) # the same
# }