st: Re: Testing Equality of Gini Coefficients

[Mike Lacy <Michael.Lacy@colostate.edu>]

In general, bootstrap approaches simulate the distribution of a 
statistic under the assumption that the alternative hypothesis is 
true, *not* under the assumption that the null is true, as an 
hypothesis test would require. In some cases,the null and alternative 
distributions have the same standard errors and the same shape, but 
not in general.  If you truly want a *test* for the difference of two 
Gini coefficients, as opposed to checking whether a CI for the 
difference contains (which is not truly an hypothesis test), I would 
recommend you use -permute- rather than bootstrap, since -permute- 
simulates the sampling distribution under the null assumption of 
random assignment to groups.

Regards,

=-=-=-=-=-=-=-=-=-=-=-=-=
Mike Lacy, Assoc. Prof.
Soc. Dept., Colo. State. Univ.
Fort Collins CO 80523 USA
(970)-491-6721   

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