作者tokyo291 (工口工口)
看板Statistics
標題[問題] 檢定poisson or negative binomial
時間Sun Dec 29 22:19:55 2013
出處是這一篇論文:
The analysis of zero-inflated count data: Beyond
zero-inflated Poisson regression
裡面一段提到
The choice between nested models (e.g., P versus NB) can be made using a
likelihood ratio test (LRT). However, the usual asymptotics do not apply;
since the null hypothesis of a Poisson model corresponds to a parameter value
for the shape parameter on the boundary of the parameter space, the appropriate
asymptotic distribution for this LRT statistic under the null hypothesis should
use a probability mass of 0.5 at 0 and 0.5 chi-square(1) distribution above 0.
Alternatively, the LRT statistic as chi-square(1) gives a conservative test.
Either way, we have overwhelming evidence (p < .001) for overdispersion from
the LRT in our example (see Table 1, column P versus column NB).
想請問的是他的檢定中提到0.5是0而0.5是卡方1
請問這個隨機檢定的值0.5此處作者所假設的還是有經過其他檢定推論出來的呢?
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1F：→ bmka:可以找得到證明的 12/30 10:08
2F：→ tokyo291:請問證明的關鍵字有那些呢?我搜尋randomized test 和卡方 12/30 10:23
3F：→ tokyo291:都找不太到... 12/30 10:23
4F：→ bmka:Likelihood Ratio Test in a Constrained Parameter Space 12/30 10:25
5F：推 BugEater:Great. 01/02 04:22