evaluate_smooth: Evaluate a smooth

In gratia: Graceful 'ggplot'-Based Graphics and Other Functions for GAMs Fitted Using 'mgcv'

Evaluate a smooth

Description

Evaluate a smooth at a grid of evenly spaced value over the range of the covariate associated with the smooth. Alternatively, a set of points at which the smooth should be evaluated can be supplied.

Usage

evaluate_smooth(object, ...)

## S3 method for class 'gam'
evaluate_smooth(
  object,
  smooth,
  n = 100,
  newdata = NULL,
  unconditional = FALSE,
  overall_uncertainty = TRUE,
  dist = 0.1,
  ...
)

## S3 method for class 'gamm'
evaluate_smooth(object, ...)

## S3 method for class 'list'
evaluate_smooth(object, ...)

Arguments

object	an object of class "gam" or "gamm".
...	arguments passed to other methods.
smooth	character; a single smooth to evaluate.
n	numeric; the number of points over the range of the covariate at which to evaluate the smooth.
newdata	a vector or data frame of points at which to evaluate the smooth.
unconditional	logical; should confidence intervals include the uncertainty due to smoothness selection? If TRUE, the corrected Bayesian covariance matrix will be used.
overall_uncertainty	logical; should the uncertainty in the model constant term be included in the standard error of the evaluate values of the smooth?
dist	numeric; if greater than 0, this is used to determine when a location is too far from data to be plotted when plotting 2-D smooths. The data are scaled into the unit square before deciding what to exclude, and dist is a distance within the unit square. See mgcv::exclude.too.far() for further details.

Details

evaluate_smooth() is deprecated in favour of smooth_estimates(), which provides a cleaner way to evaluate a smooth over a range of covariate values. smooth_estimates() can handle a much wider range of models than evaluate_smooth() is capable of and smooth_estimates() is much easier to extend to handle new smooth types.

Most code that uses evaluate_smooth() should work simply by changing the function call to smooth_estimates(). However, there are some differences:

• the newdata argument becomes data

Consider evaluate_smooth() to be soft-deprecated; its use is discouraged and it may be removed at a later date if it becomes difficult to maintain the current functionality, but there are no intentions of removing it from gratia unless that situation arises.

Value

A data frame, which is of class "evaluated_1d_smooth" or evaluated_2d_smooth, which inherit from classes "evaluated_smooth" and "data.frame".

Examples

load_mgcv()

dat <- data_sim("eg1", n = 500, dist = "normal", scale = 1, seed = 2)
m1 <- gam(y ~ s(x0) + s(x1) + s(x2) + s(x3), data = dat, method = "REML")

evaluate_smooth(m1, "s(x1)")

## 2d example
dat <- data_sim("eg2", n = 1000, dist = "normal", scale = 1, seed = 2)
m2 <- gam(y ~ s(x, z, k = 30), data = dat, method = "REML")

evaluate_smooth(m2, "s(x,z)", n = 50)

gratia documentation built on Feb. 16, 2023, 10:40 p.m.