st: xtlogit

[Traci A Schlesinger <tracias@Princeton.EDU>]

Hi Statalisters:

when running a number of conditional fixed effect logits using the xtlogit
command, i ran into the following problem:
several of my regressions return blanks (actually "."s) for the results. when
i run the same regressions by year this does not happen (the data contains 5
years:  the problem occurs only when i am aggregating years).  The problem
remains when i use only one independent variable (e.g. xtlogit incar black, fe
i (county)).  I have pasted one such result below.  if anyone can tell me what
is wrong or what i can do to fix it, that would be wonderful.

Thanks!!
traci

xtlogit incar black latino age agesq murder rape robbery assault oviolent
burglary theft oproperty drugt odrug weapons driving  chg1att totchgs1
released rearr1 cjstatus priorfta prifconv privconv pridconv pripris prijail,
fe i(county);

note: multiple positive outcomes within groups encountered.
Iteration 0:   log likelihood = -8.988e+307

Conditional fixed-effects logit                 Number of obs      =     38382

Group variable (i) : county                     Number of groups   =        54

                                                            Obs per group: min
=       102
                                                               avg =     710.8

                                                               max =      4673

                                                            LR chi2(27)
=         .
Log likelihood  =          .                        Prob > chi2
=         .


incar       Coef.   Std. Err.      z    P>|z|     [95% Conf. Interval]

black                      .        .       .            .           .
latino                      .        .       .            .           .
age                      .        .       .            .           .
agesq                      .        .       .            .           .
murder                      .        .       .            .           .
rape                      .        .       .            .           .
robbery                      .        .       .            .           .
assault                      .        .       .            .           .
oviolent                      .        .       .            .           .
burglary                      .        .       .            .           .
theft                      .        .       .            .           .
oproperty                      .        .       .            .           .
drugt                      .        .       .            .           .
odrug                      .        .       .            .           .
weapons                      .        .       .            .           .
driving                      .        .       .            .           .
chg1att                      .        .       .            .           .
totchgs1                      .        .       .            .           .
released                      .        .       .            .           .
 rearr1                      .        .       .            .           .
cjstatus                      .        .       .            .           .
priorfta                      .        .       .            .           .
prifconv                      .        .       .            .           .
privconv                      .        .       .            .           .
pridconv                      .        .       .            .           .
pripris                      .        .       .            .           .
prijail                      .        .       .            .           .





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