Mercurial > octave-nkf
annotate scripts/statistics/tests/z_test.m @ 17295:2946888dfa56
z_test.m: Fix typo in string concatenation.
* scripts/statistics/tests/z_test.m: Replace ')' with ']' to end matrix string
concatenation.
| author | Rik <rik@octave.org> |
|---|---|
| date | Tue, 20 Aug 2013 11:42:23 -0700 |
| parents | bc924baa2c4e |
| children | 1c89599167a6 |
| rev | line source |
|---|---|
|
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72c96de7a403
maint: update copyright notices for 2012
John W. Eaton <jwe@octave.org>
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changeset
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1 ## Copyright (C) 1995-2012 Kurt Hornik |
| 3426 | 2 ## |
| 3922 | 3 ## This file is part of Octave. |
| 4 ## | |
| 5 ## Octave is free software; you can redistribute it and/or modify it | |
| 6 ## under the terms of the GNU General Public License as published by | |
| 7016 | 7 ## the Free Software Foundation; either version 3 of the License, or (at |
| 8 ## your option) any later version. | |
| 3426 | 9 ## |
| 3922 | 10 ## Octave is distributed in the hope that it will be useful, but |
| 3200 | 11 ## WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 3426 | 13 ## General Public License for more details. |
| 14 ## | |
| 3200 | 15 ## You should have received a copy of the GNU General Public License |
| 7016 | 16 ## along with Octave; see the file COPYING. If not, see |
| 17 ## <http://www.gnu.org/licenses/>. | |
| 3200 | 18 |
| 3454 | 19 ## -*- texinfo -*- |
| 20 ## @deftypefn {Function File} {[@var{pval}, @var{z}] =} z_test (@var{x}, @var{m}, @var{v}, @var{alt}) | |
| 21 ## Perform a Z-test of the null hypothesis @code{mean (@var{x}) == | |
| 22 ## @var{m}} for a sample @var{x} from a normal distribution with unknown | |
| 23 ## mean and known variance @var{v}. Under the null, the test statistic | |
| 24 ## @var{z} follows a standard normal distribution. | |
| 3200 | 25 ## |
| 3454 | 26 ## With the optional argument string @var{alt}, the alternative of |
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doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
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27 ## interest can be selected. If @var{alt} is @qcode{"!="} or |
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bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
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28 ## @qcode{"<>"}, the null is tested against the two-sided alternative |
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doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
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29 ## @code{mean (@var{x}) != @var{m}}. If @var{alt} is @qcode{">"}, the |
| 3457 | 30 ## one-sided alternative @code{mean (@var{x}) > @var{m}} is considered. |
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31 ## Similarly for @qcode{"<"}, the one-sided alternative @code{mean |
| 3457 | 32 ## (@var{x}) < @var{m}} is considered. The default is the two-sided |
| 33 ## case. | |
| 3200 | 34 ## |
| 3454 | 35 ## The p-value of the test is returned in @var{pval}. |
| 3426 | 36 ## |
| 3200 | 37 ## If no output argument is given, the p-value of the test is displayed |
| 3426 | 38 ## along with some information. |
| 3454 | 39 ## @end deftypefn |
| 3200 | 40 |
| 5428 | 41 ## Author: KH <Kurt.Hornik@wu-wien.ac.at> |
| 3456 | 42 ## Description: Test for mean of a normal sample with known variance |
| 3200 | 43 |
| 44 function [pval, z] = z_test (x, m, v, alt) | |
| 3426 | 45 |
| 3200 | 46 if ((nargin < 3) || (nargin > 4)) |
| 6046 | 47 print_usage (); |
| 3200 | 48 endif |
| 3426 | 49 |
| 4030 | 50 if (! isvector (x)) |
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Use uppercase for variable names in error() strings to match Info documentation. Only m-files done.
Rik <octave@nomad.inbox5.com>
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51 error ("z_test: X must be a vector"); |
| 3200 | 52 endif |
| 4030 | 53 if (! isscalar (m)) |
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Use uppercase for variable names in error() strings to match Info documentation. Only m-files done.
Rik <octave@nomad.inbox5.com>
parents:
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54 error ("z_test: M must be a scalar"); |
| 3200 | 55 endif |
| 4030 | 56 if (! (isscalar (v) && (v > 0))) |
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11472
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Use uppercase for variable names in error() strings to match Info documentation. Only m-files done.
Rik <octave@nomad.inbox5.com>
parents:
8920
diff
changeset
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57 error ("z_test: V must be a positive scalar"); |
| 3200 | 58 endif |
| 3426 | 59 |
| 3200 | 60 n = length (x); |
| 61 z = sqrt (n/v) * (sum (x) / n - m); | |
| 62 cdf = stdnormal_cdf (z); | |
| 3426 | 63 |
| 3200 | 64 if (nargin == 3) |
| 65 alt = "!="; | |
| 66 endif | |
| 67 | |
| 5443 | 68 if (! ischar (alt)) |
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11472
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Use uppercase for variable names in error() strings to match Info documentation. Only m-files done.
Rik <octave@nomad.inbox5.com>
parents:
8920
diff
changeset
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69 error ("z_test: ALT must be a string"); |
| 3200 | 70 elseif (strcmp (alt, "!=") || strcmp (alt, "<>")) |
| 71 pval = 2 * min (cdf, 1 - cdf); | |
| 72 elseif (strcmp (alt, ">")) | |
| 73 pval = 1 - cdf; | |
| 74 elseif (strcmp (alt, "<")) | |
| 75 pval = cdf; | |
| 76 else | |
| 3456 | 77 error ("z_test: option %s not recognized", alt); |
| 3200 | 78 endif |
| 3426 | 79 |
| 3200 | 80 if (nargout == 0) |
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Use ... instead of \ for line continuation marker.
Stefan Mahr <dac922@gmx.de>
parents:
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81 s = ["Z-test of mean(x) == %g against mean(x) %s %g,\n", ... |
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7babcdb9bc13
Use ... instead of \ for line continuation marker.
Stefan Mahr <dac922@gmx.de>
parents:
16994
diff
changeset
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82 "with known var(x) == %g:\n", ... |
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17295
2946888dfa56
z_test.m: Fix typo in string concatenation.
Rik <rik@octave.org>
parents:
17281
diff
changeset
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83 " pval = %g\n"]; |
| 3200 | 84 printf (s, m, alt, m, v, pval); |
| 85 endif | |
| 86 | |
| 87 endfunction |