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diff --git a/octave_packages/m/statistics/tests/anova.m b/octave_packages/m/statistics/tests/anova.m
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+## Copyright (C) 1995-2012 Kurt Hornik
+##
+## This file is part of Octave.
+##
+## Octave is free software; you can redistribute it and/or modify it
+## under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or (at
+## your option) any later version.
+##
+## Octave is distributed in the hope that it will be useful, but
+## WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+## General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with Octave; see the file COPYING.  If not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- 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.
+##
+## 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.
+##
+## 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 @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@wu-wien.ac.at>
+## Description: One-way analysis of variance (ANOVA)
+
+function [pval, f, df_b, df_w] = anova (y, g)
+
+  if ((nargin < 1) || (nargin > 2))
+    print_usage ();
+  elseif (nargin == 1)
+    if (isvector (y))
+      error ("anova: for `anova (Y)', Y must not be a vector");
+    endif
+    [group_count, k] = size (y);
+    n = group_count * k;
+    group_mean = mean (y);
+  else
+    if (! isvector (y))
+      error ("anova: for `anova (Y, G)', Y must be a vector");
+    endif
+    n = length (y);
+    if (! isvector (g) || (length (g) != n))
+      error ("anova: G must be a vector of the same length as Y");
+    endif
+    s = sort (g);
+    i = find (s (2 : n) > s(1 : (n-1)));
+    k = length (i) + 1;
+    if (k == 1)
+      error ("anova: there should be at least 2 groups");
+    else
+      group_label = s ([1, (reshape (i, 1, k-1) + 1)]);
+    endif
+    for i = 1 : k;
+      v = y (find (g == group_label (i)));
+      group_count (i) = length (v);
+      group_mean (i) = mean (v);
+    endfor
+
+  endif
+
+  total_mean = mean (y(:));
+  SSB = sum (group_count .* (group_mean - total_mean) .^ 2);
+  SST = sumsq (reshape (y, n, 1) - total_mean);
+  SSW = SST - SSB;
+  df_b = k - 1;
+  df_w = n - k;
+  v_b = SSB / df_b;
+  v_w = SSW / df_w;
+  f = v_b / v_w;
+  pval = 1 - fcdf (f, df_b, df_w);
+
+  if (nargout == 0)
+    ## This eventually needs to be done more cleanly ...
+    printf ("\n");
+    printf ("One-way ANOVA Table:\n");
+    printf ("\n");
+    printf ("Source of Variation   Sum of Squares    df  Empirical Var\n");
+    printf ("*********************************************************\n");
+    printf ("Between Groups       %15.4f  %4d  %13.4f\n", SSB, df_b, v_b);
+    printf ("Within Groups        %15.4f  %4d  %13.4f\n", SSW, df_w, v_w);
+    printf ("---------------------------------------------------------\n");
+    printf ("Total                %15.4f  %4d\n", SST, n - 1);
+    printf ("\n");
+    printf ("Test Statistic f     %15.4f\n", f);
+    printf ("p-value              %15.4f\n", pval);
+    printf ("\n");
+  endif
+
+endfunction