NAME

welch_t_statistic - Computes the statistic for Welch's t-test

SYNOPSIS

#include "stat/stat_test.h"

Example compile flags (system dependent):
  -DLINUX_X86_64 -DLINUX_X86_64_OPTERON  -DGNU_COMPILER 
   -I/home/kobus/include
   -L/home/kobus/misc/load/linux_x86_64_opteron -L/usr/lib/x86_64-linux-gnu
  -lKJB                               -lfftw3  -lgsl -lgslcblas -ljpeg  -lSVM -lstdc++                    -lpthread -lSLATEC -lg2c    -lacml -lacml_mv -lblas -lg2c      -lncursesw 


int welch_t_statistic
(
	double m1,
	double m2,
	double v1,
	double v2,
	int n1,
	int n2,
	double *t_prime_ptr,
	int *df_ptr,
	double *effect_size_ptr
);

DESCRIPTION

This routine computes the statistic for Welch's t-test. It is safe to use this when a regular t-statistic is wanted. The Welch's version is slightly better when the statistics of sizes of the two groups are quite different. This routine provides the t-statistic degrees of freedom, and effect size. The pointer to either of this can be NULL. This is interpreted as the calling program not being interested in the corresponding result. If the p_value is wanted, then the routine welch_t_test_one_sided() can be used.

DISCLAIMER

This software is not adequatedly tested. It is recomended that results are checked independantly where appropriate.

AUTHOR

Kobus Barnard

DOCUMENTER

Kobus Barnard

SEE ALSO

welch_t_test_one_sided