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The PHREG Procedure

Testing the Global Null Hypothesis

The following three likelihood statistics can be used to test the global null hypothesis H_{0}\colon{{\beta}}=0. Under mild assumptions, each statistic has an asymptotic chi-squared distribution with p degrees of freedom given the null hypothesis. The value p is the dimension of {\beta}.

Likelihood ratio test:

\chi^2_{LR}=2 [ l (\hat{{\beta}}) - l(0) ]
Wald's test:
\chi^2_{W}=\hat{{\beta}}'[
 \hat{V}(\hat{{\beta}})]^{-1}\hat{{\beta}}
Score test:
\chi^2_{S}= [ \frac { \partial l(0) }{ \partial {{\beta}} } ]'
[ - \frac { \part...
 ...\partial {{\beta}}^2 } ]^{-1}
[ \frac { \partial l (0) }{ \partial {{\beta}} } ]

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