[SciPy-User] Any planned work on scipy.stats.distributions?
Neal Becker
ndbecker2 at gmail.com
Wed Oct 6 09:35:42 EDT 2010
josef.pktd at gmail.com wrote:
> On Tue, Oct 5, 2010 at 7:52 AM, Neal Becker <ndbecker2 at gmail.com> wrote:
>> I'm needing doubly noncentric F distribution.
>>
>> I found this:
>> http://www.ifpress.com/pdfs/comm22-897.pdf
>>
>> It might not be the best, but it's all I found.
>
> Looks interesting, I never heard of the doubly noncentric something
> distributions.
>
> Both your code and the paper are a bit stingy on explanations.
>
>>From a few examples that I tried, the precision looks pretty good. I
> found some papers that use saddle point approximation to get both pdf
> and cdf of doubly non-central f and t distributions, which might be
> faster for some use cases (e.g. evaluating the cdf or pdf at many
> points.)
>
> But for the statistics applications that I saw mentioned (needing only
> one or a few points of the cdf), your version looks good and could be
> dressed up into a scipy.stats.distributions case.
>
> Thanks,
>
> Josef
>
>
I also found
Mudholkar, Govind S., Chaubey, Yogendra P. and Ching-Chuong, Lin(1976)
Communications in Statistics - Theory and Methods, 5: 1, 49-63
Approximations for the doubly noncentral-F distribution
I haven't tried coding it (and probably won't)
More information about the SciPy-User
mailing list