changeset 3454:d8b731d3f7a3

[project @ 2000-01-18 10:13:31 by jwe]
author jwe
date Tue, 18 Jan 2000 10:13:39 +0000
parents 71d2e09c15a2
children f758be6e1730
files doc/interpreter/stats.txi scripts/ChangeLog scripts/statistics/models/logistic_regression.m scripts/statistics/models/logistic_regression_derivatives.m scripts/statistics/models/logistic_regression_likelihood.m scripts/statistics/tests/anova.m scripts/statistics/tests/bartlett_test.m scripts/statistics/tests/chisquare_test_homogeneity.m scripts/statistics/tests/chisquare_test_independence.m scripts/statistics/tests/cor_test.m scripts/statistics/tests/f_test_regression.m scripts/statistics/tests/hotelling_test.m scripts/statistics/tests/hotelling_test_2.m scripts/statistics/tests/kolmogorov_smirnov_test.m scripts/statistics/tests/kolmogorov_smirnov_test_2.m scripts/statistics/tests/kruskal_wallis_test.m scripts/statistics/tests/manova.m scripts/statistics/tests/mcnemar_test.m scripts/statistics/tests/prop_test_2.m scripts/statistics/tests/run_test.m scripts/statistics/tests/sign_test.m scripts/statistics/tests/t_test.m scripts/statistics/tests/t_test_2.m scripts/statistics/tests/t_test_regression.m scripts/statistics/tests/u_test.m scripts/statistics/tests/var_test.m scripts/statistics/tests/welch_test.m scripts/statistics/tests/wilcoxon_test.m scripts/statistics/tests/z_test.m scripts/statistics/tests/z_test_2.m
diffstat 30 files changed, 493 insertions(+), 339 deletions(-) [+]
line wrap: on
line diff
--- a/doc/interpreter/stats.txi	Tue Jan 18 08:32:15 2000 +0000
+++ b/doc/interpreter/stats.txi	Tue Jan 18 10:13:39 2000 +0000
@@ -11,11 +11,12 @@
 
 @menu
 * Basic Statistical Functions::  
+* Tests::                       
 * Models::                      
 * Distributions::               
 @end menu
 
-@node Basic Statistical Functions, Models, Statistics, Statistics
+@node Basic Statistical Functions, Tests, Statistics, Statistics
 @section Basic Statistical Functions
 
 @DOCSTRING(mean)
@@ -81,8 +82,60 @@
 @node Tests, Models, Basic Statistical Functions, Statistics
 @section Tests
 
-@node Models, Distributions, Basic Statistical Functions, Statistics
+@DOCSTRING(anova)
+
+@DOCSTRING(bartlett_test)
+
+@DOCSTRING(chisquare_test_homogeneity)
+
+@DOCSTRING(chisquare_test_independence)
+
+@DOCSTRING(cor_test)
+
+@DOCSTRING(f_test_regression)
+
+@DOCSTRING(hotelling_test)
+
+@DOCSTRING(hotelling_test_2)
+
+@DOCSTRING(kolmogorov_smirnov_test)
+
+@DOCSTRING(kolmogorov_smirnov_test_2)
+
+@DOCSTRING(kruskal_wallis_test)
+
+@DOCSTRING(manova)
+
+@DOCSTRING(mcnemar_test)
+
+@DOCSTRING(prop_test_2)
+
+@DOCSTRING(run_test)
+
+@DOCSTRING(sign_test)
+
+@DOCSTRING(t_test)
+
+@DOCSTRING(t_test_2)
+
+@DOCSTRING(t_test_regression)
+
+@DOCSTRING(u_test)
+
+@DOCSTRING(var_test)
+
+@DOCSTRING(welch_test)
+
+@DOCSTRING(wilcoxon_test)
+
+@DOCSTRING(z_test)
+
+@DOCSTRING(z_test_2)
+
+@node Models, Distributions, Tests, Statistics
 @section Models
 
+@DOCSTRING(logistic_regression)
+
 @node Distributions,  , Models, Statistics
 @section Distributions
--- a/scripts/ChangeLog	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/ChangeLog	Tue Jan 18 10:13:39 2000 +0000
@@ -21,6 +21,34 @@
 	* statistics/base/cor.m: Ditto.
 	* statistics/base/cloglog.m: Ditto.
 	* statistics/base/center.m: Ditto.
+	* statistics/models/logistic_regression.m: Ditto.
+	* statistics/models/logistic_regression_derivative.m: Ditto.
+	* statistics/models/logistic_regression_likelihood.m: Ditto.
+	* statistics/tests/anova.m: Ditto.
+	* statistics/tests/bartlett_test.m: Ditto.
+	* statistics/tests/chisquare_test_homogeneity.m: Ditto.
+	* statistics/tests/chisquare_test_independence.m: Ditto.
+	* statistics/tests/cor_test.m: Ditto.
+	* statistics/tests/f_test_regression.m: Ditto.
+	* statistics/tests/hotelling_test.m: Ditto.
+	* statistics/tests/hotelling_test_2.m: Ditto.
+	* statistics/tests/kolmogorov_smirnov_test.m: Ditto.
+	* statistics/tests/kolmogorov_smirnov_test_2.m: Ditto.
+	* statistics/tests/kruskal_wallis_test.m: Ditto.
+	* statistics/tests/manova.m: Ditto.
+	* statistics/tests/mcnemar_test.m: Ditto.
+	* statistics/tests/prop_test_2.m: Ditto.
+	* statistics/tests/run_test.m: Ditto.
+	* statistics/tests/sign_test.m: Ditto.
+	* statistics/tests/t_test.m: Ditto.
+	* statistics/tests/t_test_2.m: Ditto.
+	* statistics/tests/t_test_regression.m: Ditto.
+	* statistics/tests/u_test.m: Ditto.
+	* statistics/tests/var_test.m: Ditto.
+	* statistics/tests/welch_test.m: Ditto.
+	* statistics/tests/wilcoxon_test.m: Ditto.
+	* statistics/tests/z_test.m: Ditto.
+	* statistics/tests/z_test_2.m: Ditto.
 
 2000-01-17  John W. Eaton  <jwe@bevo.che.wisc.edu>
 
--- a/scripts/statistics/models/logistic_regression.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/models/logistic_regression.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,41 +14,60 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## Performs ordinal logistic regression.
+## -*- texinfo -*-
+## @deftypefn {Functio File} {[@var{theta}, @var{beta}, @var{dev}, @var{dl}, @var{d2l}, @var{p}] =} logistic_regression (@var{y}, @var{x}, @var{print}, @var{theta}, @var{beta})
+## Perform ordinal logistic regression.
 ##
-## Suppose Y takes values in k ordered categories, and let gamma_i (x)
-## be the cumulative probability that Y falls in one of the first i
-## categories given the covariate x.  Then
-##   [theta, beta] =
-##     logistic_regression (y, x)
+## Suppose @var{y} takes values in @var{k} ordered categories, and let
+## @code{gamma_i (@var{x})} be the cumulative probability that @var{y}
+## falls in one of the first @var{i} categories given the covariate
+## @var{x}.  Then
+##
+## @example
+## [theta, beta] = logistic_regression (y, x)
+## @end example
+##
+## @noindent
 ## fits the model
-##   logit (gamma_i (x)) = theta_i - beta' * x,   i = 1, ..., k-1.
-## The number of ordinal categories, k, is taken to be the number of
-## distinct values of round (y) .  If k equals 2, y is binary and the
-## model is ordinary logistic regression. X is assumed to have full
-## column rank.
+##
+## @example
+## logit (gamma_i (x)) = theta_i - beta' * x,   i = 1, ..., k-1
+## @end example
 ##
-##   theta = logistic_regression (y)
+## The number of ordinal categories, @var{k}, is taken to be the number
+## of distinct values of @code{round (@var{y})}.  If @var{k} equals 2,
+## @var{y} is binary and the model is ordinary logistic regression.  The
+## matrix @var{x} is assumed to have full column rank.
+##
+## Given @var{y} only, @code{theta = logistic_regression (y)}
 ## fits the model with baseline logit odds only.
 ##
 ## The full form is
-##   [theta, beta, dev, dl, d2l, gamma] =
-##     logistic_regression (y, x, print, theta, beta)
-## in which all output arguments and all input arguments except y are
-## optional.
+##
+## @example
+## [theta, beta, dev, dl, d2l, gamma]
+##    = logistic_regression (y, x, print, theta, beta)
+## @end example
+##
+## @noindent
+## in which all output arguments and all input arguments except @var{y}
+## are optional.
 ##
-## print = 1 requests summary information about the fitted model to be
-## displayed; print = 2 requests information about convergence at each
-## iteration. Other values request no information to be displayed. The
-## input arguments `theta' and `beta' give initial estimates for theta
-## and beta.
+## Stting @var{print} to 1 requests summary information about the fitted
+## model to be displayed.  Setting @var{print} to 2 requests information
+## about convergence at each iteration.  Other values request no
+## information to be displayed.  The input arguments @var{theta} and
+## @var{beta} give initial estimates for @var{theta} and @var{beta}.
+##
+## The returned value @var{dev} holds minus twice the log-likelihood.
 ##
-## `dev' holds minus twice the log-likelihood.
+## The returned values @var{dl} and @var{d2l} are the vector of first
+## and the matrix of second derivatives of the log-likelihood with
+## respect to @var{theta} and @var{beta}.
 ##
-## `dl' and `d2l' are the vector of first and the matrix of second
-## derivatives of the log-likelihood with respect to theta and beta.
-##
-## `p' holds estimates for the conditional distribution of Y given x.
+## @var{p} holds estimates for the conditional distribution of @var{y}
+## given @var{x}.
+## @end deftypefn
 
 ## Original for MATLAB written by Gordon K Smyth <gks@maths.uq.oz.au>,
 ## U of Queensland, Australia, on Nov 19, 1990.  Last revision Aug 3,
@@ -62,7 +81,7 @@
 ## logistic_regression_likelihood.
 
 function [theta, beta, dev, dl, d2l, p] ...
-      = logistic_regression (y, x, print, theta, beta)
+  = logistic_regression (y, x, print, theta, beta)
 
   ## check input
   y = round (vec (y));
--- a/scripts/statistics/models/logistic_regression_derivatives.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/models/logistic_regression_derivatives.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,15 +14,17 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{dl}, @var{d2l}] =} logistic_regression_derivatives (@var{x}, @var{z}, @var{z1}, @var{g}, @var{g1}, @var{p})
 ## Called by logistic_regression.  Calculates derivates of the
 ## log-likelihood for ordinal logistic regression model.
+## @end deftypefn
 
 ## Author:  Gordon K. Smyth <gks@maths.uq.oz.au>
 ## Adapted-By:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Derivates of log-likelihood in logistic regression
 
-function [dl, d2l] ...
-      = logistic_regression_derivatives (x, z, z1, g, g1, p)
+function [dl, d2l] = logistic_regression_derivatives (x, z, z1, g, g1, p)
 
   ## first derivative
   v = g .* (1 - g) ./ p; v1 = g1 .* (1 - g1) ./ p;
--- a/scripts/statistics/models/logistic_regression_likelihood.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/models/logistic_regression_likelihood.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,15 +14,17 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{g}, @var{g1}, @var{p}, @var{dev}] =} logistic_regression_likelihood (@var{y}, @var{x}, @var{beta}, @var{z}, @var{z1})
 ## Calculates likelihood for the ordinal logistic regression model.
 ## Called by logistic_regression.
+## @end deftypefn
 
 ## Author:  Gordon K. Smyth <gks@maths.uq.oz.au>
 ## Adapted-By:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Likelihood in logistic regression
 
-function [g, g1, p, dev] ...
-      = logistic_regression_likelihood (y, x, beta, z, z1)
+function [g, g1, p, dev] = logistic_regression_likelihood (y, x, beta, z, z1)
 
   e = exp ([z, x] * beta); e1 = exp ([z1, x] * beta);
   g = e ./ (1 + e); g1 = e1 ./ (1 + e1);
--- a/scripts/statistics/tests/anova.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/anova.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,26 +14,30 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## Performs a one-way analysis of variance (ANOVA).  The goal is to test
-## whether the population means of data taken from k different groups
-## are all equal.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{f}, @var{df_b}, @var{df_w}] =} anova (@var{y}, @var{g})
+## Perform a one-way analysis of variance (ANOVA).  The goal is to test
+## whether the population means of data taken from @var{k} different
+## groups are all equal.
 ##
-## anova (y, g) provides all data in a single vector y;  g is the vector
-## of corresponding group labels (e.g., numbers from 1 to k). This is
-## the general form which does not impose any restriction on the number
-## of data in each group or the group labels (other than that they must
-## be scalars).
+## Data may be given in a single vector @var{y} with groups specified by
+## a corresponding vector of group labels @var{g} (e.g., numbers from 1
+## to @var{k}). This is the general form which does not impose any
+## restriction on the number of data in each group or the group labels.
 ##
-## anova (y), where y is a matrix, treats each column as a group. This
-## form is only appropriate for balanced ANOVA where the numbers of
-## samples from each group are all equal.
+## If @var{y} is a matrix and @var{g} is omitted, each column of @var{y}
+## is treated as a group.  This form is only appropriate for balanced
+## ANOVA in which the numbers of samples from each group are all equal.
 ##
-## Under the null of constant means, the statistic f follows an F
-## distribution with df_b and df_w degrees of freedom.  pval is the
-## p-value (1 minus the CDF of this distribution at f) of the test.
+## Under the null of constant means, the statistic @var{f} follows an F
+## distribution with @var{df_b} and @var{df_w} degrees of freedom.
+##
+## The p-value (1 minus the CDF of this distribution at @var{f}) is
+## returned in @var{pval}.
 ##
 ## If no output argument is given, the standard one-way ANOVA table is
 ## printed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  One-way analysis of variance (ANOVA)
--- a/scripts/statistics/tests/bartlett_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/bartlett_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,17 +14,20 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, chisq, df] = bartlett_test (x1, ...)
-##
-## Performs a Bartlett test for the homogeneity of variances in the data
-## vectors x1, x2, ..., xk, where k > 1.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{chisq}, @var{df}] =} bartlett_test (@var{x1}, @dots{}) 
+## Perform a Bartlett test for the homogeneity of variances in the data
+## vectors @var{x1}, @var{x2}, @dots{}, @var{xk}, where @var{k} > 1.
 ##
-## Under the null of equal variances, the test statistic chisq
-## approximately ollows a chi-square distribution with df degrees of
-## freedom; pval is the p-value (1 minus the CDF of this distribution at
-## chisq) of the test.
+## Under the null of equal variances, the test statistic @var{chisq}
+## approximately ollows a chi-square distribution with @var{df} degrees of
+## freedom.
+##
+## The p-value (1 minus the CDF of this distribution at @var{chisq}) is
+## returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Bartlett test for homogeneity of variances
--- a/scripts/statistics/tests/chisquare_test_homogeneity.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/chisquare_test_homogeneity.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,19 +14,22 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, chisq, df] = chisquare_test_homogeneity (x, y, c)
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{chisq}, @var{df}] =} chisquare_test_homogeneity (@var{x}, @var{y}, @var{c})
+## Given two samples @var{x} and @var{y}, perform a chisquare test for
+## homogeneity of the null hypothesis that @var{x} and @var{y} come from
+## the same distribution, based on the partition induced by the
+## (strictly increasing) entries of @var{c}.
 ##
-## Given two samples x and y, perform a chisquare test for homogeneity
-## of the null hypothesis that x and y come from the same distribution,
-## based on the partition induced by the (strictly increasing) entries
-## of c.
+## For large samples, the test statistic @var{chisq} approximately follows a
+## chisquare distribution with @var{df} = @code{length (@var{c})}
+## degrees of freedom.
 ##
-## For large samples, the test statistic chisq approximately follows a
-## chisquare distribution with df = length(c) degrees pf freedom. pval
-## is the p-value (1 minus the CDF of this distribution at chisq) of the
-## test.
+## The p-value (1 minus the CDF of this distribution at @var{chisq}) is
+## returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Chi-square test for homogeneity
--- a/scripts/statistics/tests/chisquare_test_independence.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/chisquare_test_independence.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,16 +14,18 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, chisq, df] = chisquare_test_independence (X)
-##
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{chisq}, @var{df}] =} chisquare_test_independence (@var{x})
 ## Perform a chi-square test for indepence based on the contingency
-## table X.
+## table @var{x}.  Under the null hypothesis of independence,
+## @var{chisq} approximately has a chi-square distribution with
+## @var{df} degrees of freedom.
 ##
-## Under the null hypothesis of independence, chisq approximately has a
-## chi-square distribution with df degrees of freedom. pval is the
-## p-value (1 minus the CDF of this distribution at chisq) of the test.
+## The p-value (1 minus the CDF of this distribution at chisq) of the
+## test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Chi-square test for independence
--- a/scripts/statistics/tests/cor_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/cor_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,34 +14,45 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  cor_test (X, Y [, ALTERNATIVE [, METHOD]])
-##
-## Test whether two samples X and Y come from uncorrelated populations.
+## -*- texinfo -*-
+## @deftypefn {Function File} {} cor_test (@var{x}, @var{y}, @var{alt}, @var{method})
+## Test whether two samples @var{x} and @var{y} come from uncorrelated
+## populations.
 ##
-## The optional argument string ALTERNATIVE describes the alternative
-## hypothesis, and can be "!=" or "<>" (non-zero), ">" (greater than 0),
-## or "<" (less than 0).  The default is the two-sided case.
+## The optional argument string @var{alt} describes the alternative
+## hypothesis, and can be @code{"!="} or @code{"<>"} (non-zero),
+## @code{">"} (greater than 0), or @code{"<"} (less than 0).  The
+## default is the two-sided case.
 ##
-## The optional argument string METHOD specifies on which correlation
-## coefficient the test should be based.
-## If METHOD is "pearson" (default), the (usual) Pearson's product
-## moment correlation coefficient is used.  In this case, the data
-## should come from a bivariate normal distribution.  Otherwise, the
-## other two methods offer nonparametric alternatives.
-## If METHOD is "kendall", then Kendall's rank correlation tau is used.
-## If METHOD is "spearman", then Spearman's rank correlation rho is used.
-## Only the first character is necessary.
+## The optional argument string @var{method} specifies on which
+## correlation coefficient the test should be based.  If @var{method} is
+## @code{"pearson"} (default), the (usual) Pearson's product moment
+## correlation coefficient is used.  In this case, the data should come
+## from a bivariate normal distribution.  Otherwise, the other two
+## methods offer nonparametric alternatives. If @var{method} is
+## @code{"kendall"}, then Kendall's rank correlation tau is used.  If
+## @var{method} is @code{"spearman"}, then Spearman's rank correlation
+## rho is used.  Only the first character is necessary.
 ##
 ## The output is a structure with the following elements:
-##      pval            The p-value of the test.
-##      stat            The value of the test statistic.
-##      dist            The distribution of the test statistic.
-##      params          The parameters of the null distribution of the
-##                      test statistic.
-##      alternative     The alternative hypothesis.
-##      method          The method used for testing.
 ##
-## If no output argument is given, the pval is displayed.
+## @table @var
+## @item pval
+## The p-value of the test.
+## @item stat
+## The value of the test statistic.
+## @item dist
+## The distribution of the test statistic.
+## @item params
+## The parameters of the null distribution of the test statistic.
+## @item alternative
+## The alternative hypothesis.
+## @item method
+## The method used for testing.
+## @end table
+##
+## If no output argument is given, the p-value is displayed.
+## @end deftypefn
 
 ## Author:  FL <Friedrich.Leisch@ci.tuwien.ac.at>
 ## Adapted-by:  KH <Kurt.Hornik@ci.tuwien.ac.at>
--- a/scripts/statistics/tests/f_test_regression.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/f_test_regression.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,18 +14,21 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, f, df_num, df_den] = f_test_regression (y, X, R [, r])
-##
-## Performs an F test for the null hypothesis R * b = r in a classical
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{f}, @var{df_num}, @var{df_den}] =} f_test_regression (@var{y}, @var{X}, @var{R}, @var{r})
+## Perform an F test for the null hypothesis R * b = r in a classical
 ## normal regression model y = X * b + e.
 ##
-## Under the null, the test statistic f follows an F distribution with
-## df_num and df_den degrees of freedom;  pval is the p-value (1 minus
-## the CDF of this distribution at f) of the test.
+## Under the null, the test statistic @var{f} follows an F distribution
+## with @var{df_num} and @var{df_den} degrees of freedom.
 ##
-## If not given explicitly, r = 0.
+## The p-value (1 minus the CDF of this distribution at @var{f}) is
+## returned in @var{pval}.
+##
+## If not given explicitly, @var{r} = 0.
 ##
 ## If no output argument is given, the p-value is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Test linear hypotheses in linear regression model
--- a/scripts/statistics/tests/hotelling_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/hotelling_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,19 +14,21 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, Tsq] = hotelling_test (x, m)
-##
-## For a sample x from a multivariate normal distribution with unknown
-## mean and covariance matrix, test the null hypothesis that mean (x) ==
-## m.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{Tsq}] =} hotelling_test (@var{x}, @var{m})
+## For a sample @var{x} from a multivariate normal distribution with unknown
+## mean and covariance matrix, test the null hypothesis that @code{mean
+## (@var{x}) == @var{m}}.
 ##
-## Tsq is Hotelling's T^2.  Under the null, (n-p) T^2 / (p(n-1)) has an
-## F distribution with p and n-p degrees of freedom, where n and p are
-## the numbers of samples and variables, respectively.
+## Hotelling's T^2 is returned in @var{Tsq}.  Under the null,
+## @math{(n-p) T^2 / (p(n-1))} has an F distribution with @math{p} and
+## @math{n-p} degrees of freedom, where @math{n} and @math{p} are the
+## numbers of samples and variables, respectively.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Test for mean of a multivariate normal
--- a/scripts/statistics/tests/hotelling_test_2.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/hotelling_test_2.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,21 +14,28 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, Tsq] = hotelling_test_2 (x, y)
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{Tsq}] =} hotelling_test_2 (@var{x}, @var{y})
+## For two samples @var{x} from multivariate normal distributions with
+## the same number of variables (columns), unknown means and unknown
+## equal covariance matrices, test the null hypothesis @code{mean
+## (@var{x}) == mean (@var{y})}.
 ##
-## For two samples x from multivariate normal distributions with the
-## same number of variables (columns), unknown means and unknown equal
-## covariance matrices, test the null hypothesis mean (x) == mean (y).
+## Hotelling's two-sample T^2 is returned in @var{Tsq}.  Under the null,
 ##
-## Tsq is Hotelling's two-sample T^2.  Under the null,
-##    (n_x+n_y-p-1) T^2 / (p(n_x+n_y-2))
-## has an F distribution with p and n_x+n_y-p-1 degrees of freedom,
-## where n_x and n_y are the sample sizes and p is the number of
-## variables.
+## @example
+## (n_x+n_y-p-1) T^2 / (p(n_x+n_y-2))
+## @end example
 ##
-## pval is the p-value of the test.
+## @noindent
+## has an F distribution with @math{p} and @math{n_x+n_y-p-1} degrees of
+## freedom, where @math{n_x} and @math{n_y} are the sample sizes and
+## @math{p} is the number of variables.
+##
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Compare means of two multivariate normals
--- a/scripts/statistics/tests/kolmogorov_smirnov_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/kolmogorov_smirnov_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,31 +14,34 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:
-##   [pval, ks] = kolmogorov_smirnov_test (x, dist [, params] [, alt])
-##
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{ks}] =} kolmogorov_smirnov_test (@var{x}, @var{dist}, @var{params}, @var{alt})
+## Perform a Kolmogorov-Smirnov test of the null hypothesis that the
+## sample @var{x} comes from the (continuous) distribution dist. I.e.,
+## if F and G are the CDFs corresponding to the sample and dist,
+## respectively, then the null is that F == G.
 ##
-## Performs a Kolmogorov-Smirnov test of the null hypothesis that the
-## sample x comes from the (continuous) distribution dist. I.e., if F
-## and G are the CDFs corresponding to the sample and dist, respectively,
-## then the null is that F == G.
+## The optional argument @var{params} contains a list of parameters of
+## @var{dist}.  For example, to test whether a sample @var{x} comes from
+## a uniform distribution on [2,4], use
 ##
-## The optional argument params contains a list of parameters of dist.
-## E.g., to test whether a sample x comes from a uniform distribution on
-## [2,4], use `kolmogorov_smirnov_test(x, "uniform", 2, 4)'.
+## @example
+## kolmogorov_smirnov_test(x, "uniform", 2, 4)
+## @end example
 ##
-## With the optional argument string alt, the alternative of interest
-## can be selected. If alt is "!=" or "<>", the null is tested against
-## the two-sided alternative F != G.  In this case, the test statistic
-## ks follows a two-sided Kolmogorov-Smirnov distribution.
-## If alt is ">", the one-sided alternative F > G is considered,
-## similarly for "<".  In this case, the test statistic ks has a
-## one-sided Kolmogorov-Smirnov distribution.
-## The default is the two-sided case.
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative F
+## != G.  In this case, the test statistic @var{ks} follows a two-sided
+## Kolmogorov-Smirnov distribution.  If @var{alt} is @code{">"}, the
+## one-sided alternative F > G is considered, similarly for @code{"<"}.
+## In this case, the test statistic @var{ks} has a one-sided
+## Kolmogorov-Smirnov distribution.  The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  One-sample Kolmogorov-Smirnov test
--- a/scripts/statistics/tests/kolmogorov_smirnov_test_2.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/kolmogorov_smirnov_test_2.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,26 +14,27 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, ks] = kolmogorov_smirnov_test_2 (x, y [, alt])
-##
-## Performs a 2-sample Kolmogorov-Smirnov test of the null hypothesis
-## that the samples x and y come from the same (continuous) distribution.
-## I.e., if F and G are the CDFs corresponding to the x and y samples,
-## respectively, then the null is that F == G.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{ks}] =} kolmogorov_smirnov_test_2 (@var{x}, @var{y}, @var{alt})
+## Perform a 2-sample Kolmogorov-Smirnov test of the null hypothesis
+## that the samples @var{x} and @var{y} come from the same (continuous)
+## distribution.  I.e., if F and G are the CDFs corresponding to the
+## @var{x} and @var{y} samples, respectively, then the null is that F ==
+## G.
 ##
-## With the optional argument string alt, the alternative of interest
-## can be selected.
-## If alt is "!=" or "<>", the null is tested against the two-sided
-## alternative F != G.  In this case, the test statistic ks follows a
-## two-sided Kolmogorov-Smirnov distribution.
-## If alt is ">", the one-sided alternative F > G is considered,
-## similarly for "<".  In this case, the test statistic ks has a
-## one-sided Kolmogorov-Smirnov distribution.
-## The default is the two-sided case.
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative F
+## != G.  In this case, the test statistic @var{ks} follows a two-sided
+## Kolmogorov-Smirnov distribution.  If @var{alt} is @code{">"}, the
+## one-sided alternative F > G is considered, similarly for @code{"<"}.
+## In this case, the test statistic @var{ks} has a one-sided
+## Kolmogorov-Smirnov distribution.  The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Two-sample Kolmogorov-Smirnov test
--- a/scripts/statistics/tests/kruskal_wallis_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/kruskal_wallis_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,19 +14,23 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, k, df] = kruskal_wallis_test (x1, ...)
-##
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{k}, @var{df}] =} kruskal_wallis_test (@var{x1}, @dots{})
 ## Perform a Kruskal-Wallis one-factor "analysis of variance".
 ##
-## Suppose a variable is observed for k > 1 different groups, and let
-## x1, ..., xk be the corresponding data vectors.
+## Suppose a variable is observed for @var{k} > 1 different groups, and
+## let @var{x1}, @dots{}, @var{xk} be the corresponding data vectors.
 ##
 ## Under the null hypothesis that the ranks in the pooled sample are not
-## affected by the group memberships, the test statistic k is
-## approximately chi-square with df = k - 1 degrees of freedom. pval is
-## the p-value (1 minus the CDF of this distribution at k) of this test.
+## affected by the group memberships, the test statistic @var{k} is
+## approximately chi-square with @var{df} = @var{k} - 1 degrees of
+## freedom.
 ##
-## If no output argument is given, the pval is displayed.
+## The p-value (1 minus the CDF of this distribution at @var{k}) is
+## returned in @var{pval}.
+##
+## If no output argument is given, the p-value is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Kruskal-Wallis test
--- a/scripts/statistics/tests/manova.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/manova.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,21 +14,21 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  manova (Y, g)
-##
-## Performs a one-way multivariate analysis of variance (MANOVA). The
+## -*- texinfo -*-
+## @deftypefn {Function File} {} manova (@var{y}, @var{g})
+## Perform a one-way multivariate analysis of variance (MANOVA). The
 ## goal is to test whether the p-dimensional population means of data
-## taken from k different groups are all equal.  All data are assumed
-## drawn independently from p-dimensional normal distributions with the
-## same covariance matrix.
+## taken from @var{k} different groups are all equal.  All data are
+## assumed drawn independently from p-dimensional normal distributions
+## with the same covariance matrix.
 ##
-## Y is the data matrix.  As usual, rows are observations and columns
-## are variables.  g is the vector of corresponding group labels (e.g.,
-## numbers from 1 to k), so that necessarily, length (g) must be the
-## same as rows (Y).
+## The data matrix is given by @var{y}.  As usual, rows are observations
+## and columns are variables.  The vector @var{g} specifies the
+## corresponding group labels (e.g., numbers from 1 to @var{k}).
 ##
 ## The LR test statistic (Wilks' Lambda) and approximate p-values are
 ## computed and displayed.
+## @end deftypefn
 
 ## Three test statistics (Wilks, Hotelling-Lawley, and Pillai-Bartlett)
 ## and corresponding approximate p-values are calculated and displayed.
--- a/scripts/statistics/tests/mcnemar_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/mcnemar_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,17 +14,20 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, chisq, df] = mcnemar_test (x)
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{chisq}, @var{df}] =} mcnemar_test (@var{x})
+## For a square contingency table @var{x} of data cross-classified on
+## the row and column variables, McNemar's test can be used for testing
+## the null hypothesis of symmetry of the classification probabilities.
 ##
-## For a square contingency table x of data cross-classified on the row
-## and column variables, McNemar's test can be used for testing the null
-## hypothesis of symmetry of the classification probabilities.
+## Under the null, @var{chisq} is approximately distributed as chisquare
+## with @var{df} degrees of freedom.
 ##
-## Under the null, chisq is approximately distributed as chisquare with
-## df degrees of freedom, and pval is the p-value (1 minus the CDF of
-## this distribution at chisq) of the test.
+## The p-value (1 minus the CDF of this distribution at @var{chisq}) is
+## returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  McNemar's test for symmetry
--- a/scripts/statistics/tests/prop_test_2.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/prop_test_2.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,25 +14,25 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, z] = prop_test_2 (x1, n1, x2, n2 [, alt])
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{z}] =} prop_test_2 (@var{x1}, @var{n1}, @var{x2}, @var{n2}, @var{alt})
+## If @var{x1} and @var{n1} are the counts of successes and trials in
+## one sample, and @var{x2} and @var{n2} those in a second one, test the
+## null hypothesis that the success probabilities @var{p1} and @var{p2}
+## are the same.  Under the null, the test statistic @var{z}
+## approximately follows a standard normal distribution.
 ##
-## If x1 and n1 are the counts of successes and trials in one sample,
-## and x2 and n2 those in a second one, test the null hypothesis that
-## the success probabilities p1 and p2 are the same.
-## Under the null, the test statistic z approximately follows a
-## standard normal distribution.
-##
-## With the optional argument string alt, the alternative of interest
-## can be selected.
-## If alt is "!=" or "<>", the null is tested against the two-sided
-## alternative p1 != p2.
-## If alt is ">", the one-sided alternative p1 > p2 is used, similarly
-## for "<".
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative
+## @var{p1} != @var{p2}.  If @var{alt} is @code{">"}, the one-sided
+## alternative @var{p1} > @var{p2} is used, similarly for @code{"<"}.
 ## The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Compare two proportions
--- a/scripts/statistics/tests/run_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/run_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,13 +14,16 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, chisq] = run_test (x)
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{chisq}] =} run_test (@var{x})
+## Perform a chi-square test with 6 degrees of freedom based on the
+## upward runs in the columns of @var{x}.  Can be used to test whether
+## @var{x} contains independent data.
 ##
-## Performs a chi-square test with 6 degrees of freedom based on the
-## upward runs in the columns of x.  Can be used to test whether x
-## contains independent data.
+## The p-value of the test is returned in @var{pval}.
 ##
-## If no output argument is given, the pval is displayed.
+## If no output argument is given, the p-value is displayed.
+## @end deftypefn
 
 ## Author:  FL <Friedrich.Leisch@ci.tuwien.ac.at>
 ## Description:  Run test for independence
--- a/scripts/statistics/tests/sign_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/sign_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,24 +14,26 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, b, n] = sign_test (x, y [, alt])
-##
-## For two matched-pair samples x and y, perform a sign test of the
-## null hypothesis PROB(x > y) == PROB(x < y) == 1/2.
-## Under the null, the test statistic b roughly follows a binomial
-## distribution with parameters n = sum (x != y) and p = 1/2.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{b}, @var{n}] =} sign_test (@var{x}, @var{y}, @var{alt})
+## For two matched-pair samples @var{x} and @var{y}, perform a sign test
+## of the null hypothesis PROB (@var{x} > @var{y}) == PROB (@var{x} <
+## @var{y}) == 1/2.  Under the null, the test statistic @var{b} roughly
+## follows a binomial distribution with parameters @code{@var{n} = sum
+## (@var{x} != @var{y})} and @var{p} = 1/2.
 ##
-## With the optional argument alt, the alternative of interest can be
-## selected.
-## If alt is "!=" or "<>", the null hypothesis is tested against the
-## two-sided alternative PROB(x < y) != 1/2.
-## If alt is ">", the one-sided alternative PROB(x > y) > 1/2 ("x is
-## stochastically greater than y") is considered, similarly for "<".
+## With the optional argument @code{alt}, the alternative of interest
+## can be selected.  If @var{alt} is @code{"!="} or @code{"<>"}, the
+## null hypothesis is tested against the two-sided alternative PROB
+## (@var{x} < @var{y}) != 1/2.  If @var{alt} is @code{">"}, the
+## one-sided alternative PROB (@var{x} > @var{y}) > 1/2 ("x is
+## stochastically greater than y") is considered, similarly for @code{"<"}.
 ## The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Sign test
--- a/scripts/statistics/tests/t_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/t_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,24 +14,25 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, t, df] = t_test (x, m [, alt])
-##
-## For a sample x from a normal distribution with unknown mean and
-## variance, perform a t-test of the null hypothesis mean(x) == m.
-## Under the null, the test statistic t follows a Student distribution
-## with df = length (x) - 1 degrees of freedom.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{t}, @var{df}] =} t_test (@var{x}, @var{m}, @var{alt})
+## For a sample @var{x} from a normal distribution with unknown mean and
+## variance, perform a t-test of the null hypothesis @code{mean
+## (@var{x}) == @var{m}}.  Under the null, the test statistic @var{t}
+## follows a Student distribution with @code{@var{df} = length (@var{x})
+## - 1} degrees of freedom.
 ##
-## With the optional argument string alt, the alternative of interest
-## can be selected.
-## If alt is "!=" or "<>", the null is tested against the two-sided
-## alternative mean(x) != m.
-## If alt is ">", the one-sided alternative mean(x) > m is considered,
-## similarly for "<".
-## The default is the two-sided case.
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative
+## @code{mean (@var{x}) != @var{m}}.  If @var{alt} is @code{">"}, the
+## one-sided alternative @code{mean (@var{x}) > @var{m}} is considered,
+## similarly for @var{"<"}.  The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Student's one-sample t test
--- a/scripts/statistics/tests/t_test_2.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/t_test_2.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,25 +14,25 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, t, df] = t_test_2 (x, y [, alt])
-##
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{t}, @var{df}] =} t_test_2 (@var{x}, @var{y}, @var{alt})
 ## For two samples x and y from normal distributions with unknown means
 ## and unknown equal variances, perform a two-sample t-test of the null
-## hypothesis of equal means.
-## Under the null, the test statistic t follows a Student distribution
-## with df degrees of freedom.
+## hypothesis of equal means.  Under the null, the test statistic
+## @var{t} follows a Student distribution with @var{df} degrees of
+## freedom.
 ##
-## With the optional argument string alt, the alternative of interest
-## can be selected.
-## If alt is "!=" or "<>", the null is tested against the two-sided
-## alternative mean(x) != mean(y).
-## If alt is ">", the one-sided alternative mean(x) > mean(y) is used,
-## similarly for "<".
-## The default is the two-sided case.
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative
+## @code{mean (@var{x}) != mean (@var{y})}.  If @var{alt} is @code{">"},
+## the one-sided alternative @code{mean (@var{x}) > mean (@var{y})} is
+## used.  Similarly for @code{"<"}.  The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Student's two-sample t test
--- a/scripts/statistics/tests/t_test_regression.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/t_test_regression.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,26 +14,26 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, t, df] = t_test_regression (y, X, R [, r] [, alt])
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{t}, @var{df}] =} t_test_regression (@var{y}, @var{x}, @var{R}, @var{r}, @var{alt})
+## Perform an t test for the null hypothesis @code{@var{R} * @var{b} =
+## @var{r}} in a classical normal regression model @code{@var{y} =
+## @var{X} * @var{b} + @var{e}}.  Under the null, the test statistic @var{t}
+## follows a @var{t} distribution with @var{df} degrees of freedom.
 ##
-## Performs an t test for the null hypothesis R * b = r in a classical
-## normal regression model y = X * b + e.
-## Under the null, the test statistic t follows a t distribution with
-## df degrees of freedom.
-##
-## r is taken as 0 if not given explicitly.
+## If @var{r} is omitted, a value of 0 is assumed.
 ##
-## With the optional argument string alt, the alternative of interest
-## can be selected.
-## If alt is "!=" or "<>", the null is tested against the two-sided
-## alternative R * b != r.
-## If alt is ">", the one-sided alternative R * b > r is used,
-## similarly for "<".
-## The default is the two-sided case.
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative
+## @code{@var{R} * @var{b} != @var{r}}.  If @var{alt} is @code{">"}, the
+## one-sided alternative @code{@var{R} * @var{b} > @var{r}} is used.
+## Similarly for @var{"<"}.  The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Test one linear hypothesis in linear regression model
--- a/scripts/statistics/tests/u_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/u_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,25 +14,25 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, z] = u_test (x, y [, alt])
-##
-## For two samples x and y, perform a Mann-Whitney U-test of the null
-## hypothesis PROB(x > y) == 1/2 == PROB(x < y).  Under the null, the
-## test statistic z approximately follows a standard normal
-## distribution.  Note that this test is equivalent to the Wilcoxon
-## rank-sum test.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{z}] =} u_test (@var{x}, @var{y}, @var{alt})
+## For two samples @var{x} and @var{y}, perform a Mann-Whitney U-test of
+## the null hypothesis PROB (@var{x} > @var{y}) == 1/2 == PROB (@var{x}
+## < @var{y}).  Under the null, the test statistic @var{z} approximately
+## follows a standard normal distribution.  Note that this test is
+## equivalent to the Wilcoxon rank-sum test.
 ##
-## With the optional argument string alt, the alternative of interest
-## can be selected.
-## If alt is "!=" or "<>", the null is tested against the two-sided
-## alternative PROB(x > y) != 1/2.
-## If alt is ">", the one-sided alternative PROB(x > y) > 1/2 is
-## considered, similarly for "<".
-## The default is the two-sided case.
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative
+## PROB (@var{x} > @var{y}) != 1/2.  If @var{alt} is @code{">"}, the
+## one-sided alternative PROB (@var{x} > @var{y}) > 1/2 is considered,
+## similarly for @code{"<"}.  The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## This implementation is still incomplete---for small sample sizes,
 ## the normal approximation is rather bad ...
--- a/scripts/statistics/tests/var_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/var_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,25 +14,24 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, f, df_num, df_den] = var_test (x, y [, alt])
-##
-## For two samples x and y from normal distributions with unknown
-## means and unknown variances, perform an F-test of the null
-## hypothesis of equal variances.
-## Under the null, the test statistic f follows an F-distribution
-## with df_num and df_den degrees of freedom.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{f}, @var{df_num}, @var{df_den}] =} var_test (@var{x}, @var{y}, @var{alt})
+## For two samples @var{x} and @var{y} from normal distributions with
+## unknown means and unknown variances, perform an F-test of the null
+## hypothesis of equal variances.  Under the null, the test statistic f
+## follows an F-distribution with df_num and df_den degrees of freedom.
 ##
-## With the optional argument string alt, the alternative of interest
-## can be selected.
-## If alt is "!=" or "<>", the null is tested against the two-sided
-## alternative var(x) != var(y).
-## If alt is ">", the one-sided alternative var(x) > var(y) is used,
-## similarly for "<".
-## The default is the two-sided case.
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative
+## @code{var (@var{x}) != var (@var{y})}.  If @var{alt} is @code{">"},
+## the one-sided alternative @code{var (@var{x}) > var (@var{y})} is
+## used, similarly for "<".  The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  F test to compare two variances
--- a/scripts/statistics/tests/welch_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/welch_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,25 +14,25 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, t, df] = welch_test (x, y [, alt])
-##
-## For two samples x and y from normal distributions with unknown means
-## and unknown and not necessarily equal variances, perform a Welch test
-## of the null hypothesis of equal means.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{t}, @var{df}] =} welch_test (@var{x}, @var{y}, @var{alt})
+## For two samples @var{x} and @var{y} from normal distributions with
+## unknown means and unknown and not necessarily equal variances,
+## perform a Welch test of the null hypothesis of equal means.
 ## Under the null, the test statistic t approximately follows a Student
 ## distribution with df degrees of freedom.
 ##
-## With the optional argument string alt, the alternative of interest
-## can be selected.
-## If alt is "!=" or "<>", the null is tested against the two-sided
-## alternative mean(x) != m.
-## If alt is ">", the one-sided alternative mean(x) > m is considered,
-## similarly for "<".
-## The default is the two-sided case.
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative
+## @code{mean (@var{x}) != @var{m}}.  If @var{alt} is @code{">"}, the
+## one-sided alternative mean(x) > m is considered, similarly for
+## @code{"<"}.  The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Welch two-sample t test
--- a/scripts/statistics/tests/wilcoxon_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/wilcoxon_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,24 +14,24 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, z] = wilcoxon_test (x, y [, alt])
-##
-## For two matched-pair sample vectors x and y, perform a Wilcoxon
-## signed-rank test of the null hypothesis PROB(x > y) == 1/2.
-## Under the null, the test statistic z approximately follows a
-## standard normal distribution.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{z}] =} wilcoxon_test (@var{x}, @var{y}, @var{alt})
+## For two matched-pair sample vectors @var{x} and @var{y}, perform a
+## Wilcoxon signed-rank test of the null hypothesis PROB (@var{x} >
+## @var{y}) == 1/2.  Under the null, the test statistic @var{z}
+## approximately follows a standard normal distribution.
 ##
-## With the optional argument string alt, the alternative of interest
-## can be selected.
-## If alt is "!=" or "<>", the null is tested against the two-sided
-## alternative PROB(x > y) != 1/2.
-## If alt is ">", the one-sided alternative PROB(x > y) > 1/2 is
-## considered, similarly for "<".
-## The default is the two-sided case.
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative
+## PROB (@var{x} > @var{y}) != 1/2.  If alt is @code{">"}, the one-sided
+## alternative PROB (@var{x} > @var{y}) > 1/2 is considered, similarly
+## for @code{"<"}.  The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Wilcoxon signed-rank test
--- a/scripts/statistics/tests/z_test.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/z_test.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,25 +14,25 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, z] = z_test (x, m, v [, alt])
-##
-## Perform a Z-test of the null hypothesis mean(x) == m for a sample x
-## from a normal distribution with unknown mean and known variance v.
-## Under the null, the test statistic z follows a standard normal
-## distribution.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{z}] =} z_test (@var{x}, @var{m}, @var{v}, @var{alt})
+## Perform a Z-test of the null hypothesis @code{mean (@var{x}) ==
+## @var{m}} for a sample @var{x} from a normal distribution with unknown
+## mean and known variance @var{v}.  Under the null, the test statistic
+## @var{z} follows a standard normal distribution.
 ##
-## With the optional argument string alt, the alternative of interest
-## can be selected.
-## If alt is "!=" or "<>", the null is tested against the two-sided
-## alternative mean(x) != m.
-## If alt is ">", the one-sided alternative mean(x) > m is considered,
-## similarly for "<".
-## The default is the two-sided case.
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative
+## @code{mean (@var{x}) != @var{m}}.  If @var{alt} is @code{">"}, the
+## one-sided alternative @code{mean (@var{x}) > @var{m}} is considered,
+## similarly for @code{"<"}.  The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed
 ## along with some information.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Test for mean of a normal sample with known variance
--- a/scripts/statistics/tests/z_test_2.m	Tue Jan 18 08:32:15 2000 +0000
+++ b/scripts/statistics/tests/z_test_2.m	Tue Jan 18 10:13:39 2000 +0000
@@ -14,26 +14,25 @@
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-## usage:  [pval, z] = z_test_2 (x, y, v_x, v_y [, alt])
-##
-## For two samples x and y from normal distributions with unknown
-## means and known variances v_x and v_y, perform a Z-test of the
-## hypothesis of equal means.
-## Under the null, the test statistic z follows a standard normal
-## distribution.
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{pval}, @var{z}] =} z_test_2 (@var{x}, @var{y}, @var{v_x}, @var{v_y}, @var{alt})
+## For two samples @var{x} and @var{y} from normal distributions with
+## unknown means and known variances @var{v_x} and @var{v_y}, perform a
+## Z-test of the hypothesis of equal means.  Under the null, the test
+## statistic @var{z} follows a standard normal distribution.
 ##
-## With the optional argument string alt, the alternative of interest
-## can be selected.
-## If alt is "!=" or "<>", the null is tested against the two-sided
-## alternative mean(x) != mean(y).
-## If alt is ">", the one-sided alternative mean(x) > mean(y) is
-## used, similarly for "<".
-## The default is the two-sided case.
+## With the optional argument string @var{alt}, the alternative of
+## interest can be selected.  If @var{alt} is @code{"!="} or
+## @code{"<>"}, the null is tested against the two-sided alternative
+## @code{mean (@var{x}) != mean (@var{y})}.  If alt is @code{">"}, the
+## one-sided alternative @code{mean (@var{x}) > mean (@var{y})} is used,
+## similarly for @code{"<"}.  The default is the two-sided case.
 ##
-## pval is the p-value of the test.
+## The p-value of the test is returned in @var{pval}.
 ##
 ## If no output argument is given, the p-value of the test is displayed
 ## along with some information.
+## @end deftypefn
 
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Compare means of two normal samples with known variances