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help for ^lrtest2^                                    (STB-49: sg111)
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Likelihood-ratio test after model estimation using a forward strategy 
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	^lrtest2^ [^, s^aving^(^name^)^ ^u^sing^(^name^)^ ^m^odel^(^name^)^ ^d^f^(^#^)^ ]


Description
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^lrtest2^ is a simple modification of the official ^lrtest^ command, to perform
the likelihood-ratio test under a forward strategy, although a backward 
strategy is also permitted. 

^lrtest2^ saves information about and performs likelihood-ratio tests between
pairs of maximum-likelihood models such as those estimated by ^stcox^, ^logit^, 
^logistic^, ^poisson^, etc. using a forward strategy. 

^lrtest2^, typed without arguments, performs a likelihood-ratio test of the 
most recently estimated model -simplest model- against the model previously 
saved -complete model- by "^lrtest2,^ ^saving(0)^". 


Options
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^lrtest2^ has same syntax and options as ^lrtest^.


Examples
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 using ^lrtest2^ we must follow a forward strategy

 . ^logit chd age sex^                         estimate simplest model
 . ^lrtest2, saving(0)^                        save results
 . ^logit chd age age2 sex^                    estimate comlpete model
 . ^lrtest2^                                   obtain test

 while using ^lrtest^, a backward strategy must be follow

 . ^logit chd age age2 sex^                    estimate complete model
 . ^lrtest, saving(0)^                         save results
 . ^logit chd age sex^                         estimate simplest model
 . ^lrtest^                                    obtain test


Authors
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      Santiago Perez-Hoyos
      Institut Valencia d'Estudis en Salut Publica, Valencia (Spain)
      e-mail: sperez@@san.gva.es

      Aurelio Tobias
      Statistical Consultant, Getafe (Spain)
      e-mail: bledatobias@@ctv.es

      after official Stata's ^lrtest^ command


Also see
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    STB:  STB-49 sg111
 Manual:  ^[U] 26 Estimation and post-estimation commands^
	  ^[R] lrtest^
On-line:  help for @lrtest@