Extract Term Contributions to Predictor
termPredictors is a generic function which extracts the
contribution of each term to the predictor from a fitted model object.
termPredictors(object, ...)
object |
a fitted model object. |
... |
additional arguments for method functions. |
The default method assumes that the predictor is linear and calculates
the contribution of each term from the model matrix and fitted
coefficients. A method is also available for gnm objects.
A matrix with the additive components of the predictor in labelled columns.
Heather Turner
## Linear model
G <- gl(4, 6)
x <- 1:24
y <- rnorm(24, 0, 1)
lmGx <- lm(y ~ G + x)
contrib <- termPredictors(lmGx)
contrib
all.equal(as.numeric(rowSums(contrib)), as.numeric(lmGx$fitted)) #TRUE
## Generalized linear model
y <- cbind(rbinom(24, 10, 0.5), rep(10, 24))
glmGx <- glm(y ~ G + x, family = binomial)
contrib <- termPredictors(glmGx)
contrib
all.equal(as.numeric(rowSums(contrib)),
as.numeric(glmGx$linear.predictors)) #TRUE
## Generalized nonlinear model
A <- gl(4, 6)
B <- gl(6, 1, 24)
y <- cbind(rbinom(24, 10, 0.5), rep(10, 24))
set.seed(1)
gnmAB <- gnm(y ~ A + B + Mult(A, B), family = binomial)
contrib <- termPredictors(gnmAB)
contrib
all.equal(as.numeric(rowSums(contrib)),
as.numeric(gnmAB$predictors)) #TRUEPlease choose more modern alternatives, such as Google Chrome or Mozilla Firefox.