作者tokyo291 (工口工口)
看板Statistics
标题[问题] 检定poisson or negative binomial
时间Sun Dec 29 22:19:55 2013
出处是这一篇论文:
The analysis of zero-inflated count data: Beyond
zero-inflated Poisson regression
里面一段提到
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).
想请问的是他的检定中提到0.5是0而0.5是卡方1
请问这个随机检定的值0.5此处作者所假设的还是有经过其他检定推论出来的呢?
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1F：→ bmka:可以找得到证明的 12/30 10:08
2F：→ tokyo291:请问证明的关键字有那些呢?我搜寻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