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From |
Roger Harbord <rmharbord@googlemail.com> |

To |
statalist@hsphsun2.harvard.edu, "Tiago V. Pereira" <tiago.pereira@incor.usp.br> |

Subject |
Re: st: Problem with -metareg- |

Date |
Tue, 10 Feb 2009 22:03:04 +0000 |

Dear Tiago, Hard to tell what the cause of the convergence problem is as clearly i can't replicate it without the original dataset. The different behaviour when you re-input the data may be more likely to be due to the tiny differences between the original stored values and the result of re-inputting them to 6 or 7 significant figures than the presence or abscence of additional variables. If you want to email me the original dataset (to roger.harbord@bristol.ac.uk) i'll investigate further. Switching to the -mm- option (method-of-moments estimate of between study variance) instead of the -reml- option (residual maximum likelihood) should avoid the numerical problems and give the same answer in this instance where the estimated between-study variance is zero. -- Roger Harbord http://www.epi.bris.ac.uk/staff/rharbord.htm On Tue, Feb 10, 2009 at 6:41 PM, Tiago V. Pereira <tiago.pereira@incor.usp.br> wrote: > Dear Statalisters, > > Using my whole dataset (with several others variables) I type: > > . metareg logor, wsse(selogor) reml > > and obtain: > > numerical derivatives are approximate > nearby values are missing > numerical derivatives are approximate > nearby values are missing > numerical derivatives are approximate > nearby values are missing > could not calculate numerical derivatives > missing values encountered > r(430); > > Then, I do the following: clear, inpute the same data but only the two > variables and obtain sucessfully the result I am looking for: > > clear > > > */---------START------------- > input logor selogor > .0800427 .8641729 > .2786815 .1604731 > -1.400893 1.19818 > .537752 .5122404 > end > metareg logor, wsse(selogor) reml > */--------END-------------------- > > Meta-regression Number of obs = > 4 > REML estimate of between-study variance tau2 = > 0 > % residual variation due to heterogeneity I-squared_res = > 0.00% > With Knapp-Hartung modification > ------------------------------------------------------------------------------ > logor | Coef. Std. Err. t P>|t| [95% Conf. > Interval] > -------------+---------------------------------------------------------------- > _cons | .268642 .1496053 1.80 0.170 -.207469 > .7447529 > ------------------------------------------------------------------------------ > > Does anyone have a guess about what is going on with -metareg- (the most > recent version)? > > > Cheers! > > Tiago * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/

**References**:**st: Problem with -metareg-***From:*"Tiago V. Pereira" <tiago.pereira@incor.usp.br>

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