Prediction and coefficient functions for forward stepwise regression

Description

Make predictions or extract coefficients from a forward stepwise object

Usage

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## S3 method for class 'fs'
predict(object, newx, s, ...)
## S3 method for class 'fs'
coef(object, s, ...)

Arguments

object

Object returned by a call to fs function

newx

Matrix of x values at which the predictions are desired. If NULL, the x values from forward stepwise fitting are used

s

Step number(s) at which predictions or coefficients are desired

...

Additional arguments

Value

Either a vector/matrix of predictions, or a vector/matrix of coefficients.

Author(s)

Ryan Tibshirani, Rob Tibshirani, Jonathan Taylor, Joshua Loftus, Stephen Reid

Examples

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set.seed(33)
n = 200
p = 20
sigma = 1
x = matrix(rnorm(n*p),n,p)
beta = c(rep(3,10),rep(0,p-10))
y = x%*%beta + sigma*rnorm(n)

# run forward stepwise and predict functions
obj = fs(x,y)
fit = predict(obj,x,s=3)