st: Bugs in generating variables?

[Fabrice Etile <etile@ivry.inra.fr>]

Dear Stata Users,

Here is a strange output, which shows that Stata 8 has some problems for 
dealing with inequalities:

<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

       log:  c:\data\aninserm\inserm03\countmodels\logforstata.smcl
  log type:  smcl
 opened on:   4 Nov 2004, 10:53:51

[added comment : continuous is a continuous (formatted double) variable in 
the range 0-1.1]
. ta continuous

 continuous |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,156       92.55       92.55
         .1 |        241        3.12       95.67
         .2 |        150        1.94       97.61
         .3 |         99        1.28       98.89
         .4 |         48        0.62       99.51
         .5 |         23        0.30       99.81
         .6 |          6        0.08       99.88
         .7 |          6        0.08       99.96
         .9 |          2        0.03       99.99
        1.1 |          1        0.01      100.00
------------+-----------------------------------
      Total |      7,732      100.00

. g discrete=(continuous>0.1)
[added comment : I generate a discrete variable which takes value 1 if 
continuous is strictly greater than 0.1]
. ta continuous discrete

           |       discrete
continuous |         0          1 |     Total
-----------+----------------------+----------
         0 |     7,156          0 |     7,156
        .1 |         0        241 |       241
        .2 |         0        150 |       150
        .3 |         0         99 |        99
        .4 |         0         48 |        48
        .5 |         0         23 |        23
        .6 |         0          6 |         6
        .7 |         0          6 |         6
        .9 |         0          2 |         2
       1.1 |         0          1 |         1
-----------+----------------------+----------
     Total |     7,156        576 |     7,732


As you can see, observations with continuous==0.1 should have discrete==0 
and this is not what happens!!

Has someone an answer to that?

Cheers

Fabrice Etil�


PS: note that one of my colleague showed me a similar bug, so that it is 
not a hardware-related problem.


Fabrice Etil�
INRA-CORELA
65, Bvd. de Brandebourg
94205, Ivry-sur-Seine cedex
T�l: 01 49 59 69 86
Fax: 01 49 59 69 90
E-mail: etile@ivry.inra.fr
Web: http://www.ivry.inra.fr/corela/membres/etile.php

"L'ennui dans ce monde, c'est que les idiots sont s�rs d'eux et les gens 
sens�s pleins de doutes." - Bertrand Russell




 

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