[Scipy-tickets] [SciPy] #1676: Errors in t statistic , scipy.stats.test() fails due to assertion error

SciPy Trac scipy-tickets@scipy....
Wed Jun 13 08:36:08 CDT 2012


#1676: Errors in t statistic ,scipy.stats.test() fails due to assertion error
-------------------------------------+--------------------------------------
 Reporter:  blowthesax               |       Owner:  somebody   
     Type:  defect                   |      Status:  new        
 Priority:  high                     |   Milestone:  Unscheduled
Component:  scipy.stats              |     Version:  0.10.0     
 Keywords:  t test, assertion error  |  
-------------------------------------+--------------------------------------
 Using this software configuration:

 numpy version 1.6.2[[BR]]

 scipy version 0.10.1[[BR]]

 python version 2.7.3 (default, Apr 30 2012, 21:18:11) [GCC 4.7.0 20120416
 (Red Hat 4.7.0-2)][[BR]]

 nose version 1.1.2[[BR]]


 The functions in scipy.stats.t return incorrect values, especially for
 higher degrees of freedom

 example:
 In: scipy.stats.t.cdf(5,1000)
 Out: 0.92261785146237119

 Same calculation in matlab:
 In: tcdf(5, 1000)
 Out: 0.999999661637182

 scipy.stats.test() fails at test_stats.test_ttest_ind

 Report is attached to this ticket.

 Thanks for your help.

-- 
Ticket URL: <http://projects.scipy.org/scipy/ticket/1676>
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