SciencesPo (version 1.02.12)

linearAlgebra: Functions for teaching linear algebra.

Description

These functions provide a formula based interface to the construction of matrices from data and for fitting. You can use them both for numerical vectors and for functions of variables in data frames. These functions are intended to support teaching basic linear algebra with a particular connection to statistics.

Usage

mat(formula, data = parent.frame())
singvals(formula, data = parent.frame())

Arguments

formula

a formula as ~ a or ~ a + b. In mat and singvals, only the right-hand side is used.

data

a data frame from which to pull out numerical values for the variables in the formula

...

additional arguments (currently ignored)

mat returns a model matrix

To demonstrate singularity, use singvals.

Value

• mat returns a matrix

  singvals gives singular values for each column in the model matrix

encoding

UTF-8

Examples

a <- c(1,0,0); b <- c(1,2,3); c <- c(4,5,6); x <- rnorm(3)
# Formula interface
mat(~a+b)
mat(~a+b+1)

data(tobaccovote)
mat(~votedpro+party, data=tobaccovote)
singvals(~votedpro*party*money*acres, data=tobaccovote)