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globtest

PURPOSE ^

GLOBTEST performs different global tests. A global test provides one

SYNOPSIS ^

function [p] = globtest(Input,n1,samp,varargin)

DESCRIPTION ^

 GLOBTEST performs different global tests. A global test provides one
 joint statement on all endpoints, i.e. the global hypotheses is testing. 
 This function returns the corresponding p-value.
 
 
 
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INPUT

These input arguments are required:
 Input: data matrix with the size [n,k]               
 n1:    number of patients in group one (0 < n1 <= n ), 
    restricted by the kind of samp
 samp: kind of sample         
                             
           single sample       'single' (n1 = n)
           paired sample       'paired' (n1 = n/2; n must be even)
           independent sample  'indept' (n1 < n)
-----

   [...] = globtest(...,'PARAM1',VAL1,'PARAM2',VAL2,...) specifies additional
   parameters and their values.  Valid parameters are the following:
   
    Parameter        Value  

      'tail'       The alternative hypothesis against which to compute
                   p-values for testing the hypothesis of no differences.
                   Choices are:

               tail         Alternative Hypothesis            
        '~=' (the default) "there is a significant difference" (two-sided test)
               '>'                "the values of group 1 are higher than the values of group 2" (one-sided test)
               '<'                "the values of group 1 are smaller than the values of group 2" (one-sided test)    


       'B'            number of permutations
                        default: 500 
                       B must be in the intervall
                       500 <= B <= 2^n1   for single and paired sample
                       (for 2^n1 < 500 : B = min(B,2^n1)) 

                       500 <= B <= n! / n1!*(n-1)  for independent sample
                       (for n! / n1!*(n-n1)! < 500 : B = min(B,n!/n1!*(n-n1)!))

---

    'tstat'              teststatistic
                         'tmax' => is sensitive to departures in only a few endpoints 
                         'tsum' => is sensitive to departures of all endpoints in the same direction
                         'tsumabs' (the default) => is sensitive to departures of all endpoints (independent of the
                                        direction); only two-sided!!!
                         'ta' => choose this test statistic if the relative number of false hypotheses is
                                        small; only independent!
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 OUTPUT

 [p] = globtest(Input,n1,samp) returns the p-value of the global test.

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 REFERENCES:

  [1] Hemmelmann C, Horn M, Reiterer S, Schack B, Suesse T, Weiss S.
    Multivariate tests for the evaluation of high-dimensional EEG data.
    J Neurosci Methods. 2004 Oct 15;139(1):111-20. 


 Copyright (C) 2006,2007 Claudia Hemmelmann <claudia.hemmelmann@mti.uni-jena.de>
 Adapted by A Schloegl <a.schloegl@ieee.org> 2006,2007 

***
 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Library General Public
 License as published by the Free Software Foundation; either
 Version 2 of the License, or (at your option) any later version.

 This library 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
 Library General Public License for more details.

 You should have received a copy of the GNU Library General Public
 License along with this library; if not, write to the
 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 Boston, MA  02111-1307, USA.

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CROSS-REFERENCE INFORMATION ^

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