Keywords - Function groups - @ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Library: stats
See also: gls linregfs linregres doglm

Quantlet: linreg
Description: Computes the Generalized Least Squares estimate for the coefficients of a linear model.

Usage: {beta,bse,bstan,bpval} = linreg (x, y {,opt, om})
Input:
x n x p x d1 x ... x dn array, explanatory variables
y n x 1 x d1 x ... x dn array, dependent variables
opt optional string vector, options are: "notext" - no text output is generated, "display" - a special display window is generated showing the results instead of the output window itself, "nointercept" - the intercept is not included in the estimation, "omega" - the covariance matrix "om" is specified.
om optional n x n x d1 x ... x dn array, covariance matrix
Output:
beta p x 1 x d1 x ... x dn array, parameter estimates
bse p x 1 x d1 x ... x dn array, standard errors of b
bstan p x 1 x d1 x ... x dn array, standardized parameter estimates
bpval p x 1 x d1 x ... x dn array, p-values corresponding to bstan

Note:

Example:
library("stats")
setenv("outputstringformat", "%s")
randomize(1964)
n = 500
x = normal(n,3)
beta = #(10, 2, 3)
u = 0.5 * normal(n)
y = x*beta .+ u
{beta,se,betastan,p} = linreg(x,y)

Result:
Contents of out
[ 1,]
[ 2,] A  N  O  V  A                   SS      df     MSS       F-test   P-value
[ 3,] _________________________________________________________________________
[ 4,] Regression                 61494.937     3 20498.312   80164.745   0.0000
[ 5,] Residuals                    126.828   496     0.256
[ 6,] Total Variation            61621.765   499   123.491
[ 7,]
[ 8,] Multiple R      = 0.99897
[ 9,] R^2             = 0.99794
[10,] Adjusted R^2    = 0.99793
[11,] Standard Error  = 0.50567
[12,]
[13,]
[14,] PARAMETERS         Beta         SE         StandB        t-test   P-value
[15,] ________________________________________________________________________
[16,] b[ 0,]=         -0.0058       0.0227       0.0000        -0.254   0.6001
[17,] b[ 1,]=         10.0019       0.0215       0.9501       465.977   0.0000
[18,] b[ 2,]=          1.9906       0.0221       0.1839        90.263   0.0000
[19,] b[ 3,]=          3.0249       0.0231       0.2667       130.817   0.0000
Example:
library("stats")
randomize(1964)
n = 50
x = normal(n,3)
beta = #(10, 2, 3)
u = 0.5 * normal(n)
y = x*beta .+ u
covar =(0.5.*x[,2] .+ 0.3.*x[,3]+ 0.2*x[,1]).^2
y = x*beta .+ sqrt(covar).*u
{beta,se,betastan,p} = linreg(x, y,"nointercept"|"display"|"omega",diag(covar))

Result:
You see the display:
             A  N  O  V  A                   SS      df     MSS       F-test   P-value
             _________________________________________________________________________
             Regression                  4872.988     3  1624.329    8876.339   0.0000
             Residuals                      8.601    47     0.183

             R^2             = 0.98388
             Standard Error  = 0.42778


             PARAMETERS         Beta         SE
             ______________________________________
             b[ 1,]=         10.0297       0.0637
             b[ 2,]=          2.0544       0.0512
             b[ 3,]=          2.9838       0.0698



Author: S. Hannappel, 20010721
(C) MD*TECH Method and Data Technologies, 05.02.2006