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Find the Least Squares Fit

Syntax

lsfit(x, y, wt, intercept=true, tolerance=1e-07,
        yname=null)

Arguments

x a matrix whose rows correspond to cases and whose columns correspond to variables.
y the responses, possibly matrix valued if you want to fit multiple left hand sides.
wt an optional vector of weights for performing weighted least squares.
intercept whether or not an intercept term should be used.
tolerance the tolerance to be used in the matrix decomposition.
yname an unused parameter for compatibility.

Description

The least squares estimate of \bold{β} in the model \bold{Y} = \bold{X} \bold{β} + \bold{ε} is found. If weights are specified then a weighted least squares is performed with the weight given to the jth case specified by the jth entry in wt.

If any observation has a missing value in any field, that observation is removed before the analysis is carried out. This can be quite inefficient if there is a lot of missing data.

The implementation is via a modification of the LINPACK subroutines which allow for multiple left-hand sides.

Values

A list with the following named components:
coef the least squares estimates of the coefficients in the model (stated below). residuals residuals from the fit. intercept indicates whether an intercept was fitted. qr the QR decomposition of the design matrix.

See Also

ls.diag, rreg.

Examples

lsf <- lsfit(x,y) lsf <- lsfit(x,y,wt=wts)