# Re: st: "no observations"

 From Scott Cunningham To statalist@hsphsun2.harvard.edu Subject Re: st: "no observations" Date Tue, 2 May 2006 08:17:36 -0400

Richard,

Okay, that wasn't it. You were right to point out that I had included age in the varlist, which was not in the regression, but notice the following output. It doesn't seem to matter at all. What's going on here?

xi:xtpoisson rp srfm age2 hgc hhd1 i.year i.census i.year*i.census, fe i(id)
> vce(boot)
i.year _Iyear_1998-2002 (naturally coded; _Iyear_1998 omitted)
i.census _Icensus_1-4 (naturally coded; _Icensus_1 omitted)
i.year*i.census _IyeaXcen_#_# (coded as above)
(running xtpoisson on estimation sample)

Bootstrap replications (50)
----+--- 1 ---+--- 2 ---+--- 3 ---+--- 4 ---+--- 5
.................................................. 50

Conditional fixed-effects Poisson regression Number of obs = 1905
Group variable (i): id Number of groups = 636

Obs per group: min = 2
avg = 3.0
max = 3

Wald chi2(15) = 53.50
Log likelihood = -3527.8153 Prob > chi2 = 0.0000

------------------------------------------------------------------------ ------
| Observed Bootstrap Normal- based
rp | Coef. Std. Err. z P>|z| [95% Conf. Interval]
------------- +----------------------------------------------------------------
srfm | .0139139 .0078909 1.76 0.078 -. 001552 .0293799
age2 | -.0259416 .0117042 -2.22 0.027 -.0488814 -.0030018
hgc | .1280376 .064077 2.00 0.046 . 002449 .2536261
hhd1 | -.4210113 .2767025 -1.52 0.128 -. 9633383 .1213156
_Iyear_2000 | 1.316794 .9342833 1.41 0.159 -.5143679 3.147955
_Iyear_2002 | 3.629465 1.789771 2.03 0.043 .1215795 7.137351
_Icensus_2 | -.5786532 .5795236 -1.00 0.318 -1.714499 .5571921
_Icensus_3 | -.7181931 .7184449 -1.00 0.317 -2.126319 .6899329
_Icensus_4 | -1.209667 .6757717 -1.79 0.073 -2.534155 .1148217
_IyeaXce~0_2 | .6065933 .4341424 1.40 0.162 -.2443102 1.457497
_IyeaXce~0_3 | .6894538 .3806239 1.81 0.070 -.0565554 1.435463
_IyeaXce~0_4 | .8719567 .4199848 2.08 0.038 .0488016 1.695112
_IyeaXce~2_2 | -.1306399 .3759929 -0.35 0.728 -. 8675724 .6062925
_IyeaXce~2_3 | -.0121621 .3575348 -0.03 0.973 -. 7129175 .6885933
_IyeaXce~2_4 | .7304281 .594425 1.23 0.219 -. 4346235 1.89548
------------------------------------------------------------------------ ------

. mfx, dydx varlist(srfm age2 hgc hhd1)
no observations
r(2000);

. mfx, dydx varlist (srfm age2 hhd1)
no observations
r(2000);

. mfx, dydx varlist (srfm)
no observations
r(2000);

. mfx, dydx varlist (age2)
no observations
r(2000);

. mfx, dydx varlist(hhd1)
no observations
r(2000);

. mfx, dydx varlist (hgc)
no observations
r(2000);

. mfx, dydx
no observations
r(2000);

. mfx
no observations
r(2000);

. de

Contains data from nlsy.dta
obs: 2,283
vars: 122 2 May 2006 08:09
size: 682,617 (99.9% of memory free)
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/