# st: why is F statistic still missing even though there is no singleton dummy problem?

 From "Jian Zhang" To statalist@hsphsun2.harvard.edu Subject st: why is F statistic still missing even though there is no singleton dummy problem? Date Thu, 17 Aug 2006 16:50:45 -0700 (PDT)

Dear Statalisters,

I am running a ols regression on a small data set.  The reported F statistic is still mssing
although the data set doesn' have so-called singleton dummies.  Is there anyone knowing what is
going on?  Here are the data set and the regression results.  Many thanks!

. list var1 var3 var5 var6

+---------------------------+
var1   var3   var5   var6
---------------------------
1.     1    789      0      0
2.     3     45      0      0
3.     5   2358     -4      4
4.     4     65      0      0
5.     5     12     14     -7
---------------------------
6.   453     12      0      0
7.     6      4      0      0
8.    45      2      0      0
9.     8      3   -123    123
10.   897      5      0      0
---------------------------
11.    43     87      0      0
12.    43     56      0      0
13.     4     25      0      0
+---------------------------+

reg var1 var3 var5 var6,	robust nocons

Linear regression			Number of obs	=      13
F(  2,    10)	=       .
Prob > F	=       .
R-squared	=  0.0002
Root MSE	=  318.67

Robust
var1       Coef.	Std. Err.      t	P>t	[95% Conf.	Interval]

var3    .0046225	.0031     1.49	0.167	-.0022847	.0115297
var5    .7696625	.0060938   126.30	0.000	.7560848	.7832403
var6    .8329636	.007418   112.29	0.000	.8164353	.8494919

Best regards,
Jian Zhang
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