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From Phil Steitz <phil.ste...@gmail.com>
Subject Re: [math] Distributions over sample spaces other than R
Date Sat, 29 Oct 2011 22:38:56 GMT
On 10/29/11 10:20 AM, cwinter wrote:
> Phil Steitz wrote:
>> I would say pull DiscreteDistribution out.  That is where the
>> difference really lies.  I have thought about suggesting that we
>> eliminate it altogether; but I still think there may be value in
>> supporting discrete distributions over sample spaces that are not
>> embedded in the integers.
>>
>> Phil
>>
> Empirical distributions are discrete by nature. Depending on the underlying
> data, the domain is usually (a subset of) the reals or the integers.
> However, after moving probability(double) to Distribution,
> DiscreteDistribution will be an empty interface. Thus there is in fact the
> question whether it should be eliminated. Otherwise it would be just a
> "flag" for discrete distributions and that's indeed independent of the
> sample space.

Maybe it would be best to eliminate IntegerDistribution then and
merge Distribution and ContinuousDistribution, so we have two roots
- DiscreteDistribution and ContinuousDistribution.   The only reason
really to have DiscreteDistribution is if we want to support
distributions of RVs over sample spaces that are not subsets of Z. 
There does not seem to be much enthusiasm for that (i.e.
parameterizing the type of the domain of the distribution and pmf),
so we might as well just collapse Discrete and Integer.   Once you
pull out Discrete/Integer, there is not much value any more in
Distribution as a parent, so why not just drop both
IntegerDistribution and Distribution and move to two roots with
doubles / ints as domains and contracts cleaned up to deal with
discrete vs continuous cases consistently.

Phil
>
> Christian
>
> --
> View this message in context: http://apache-commons.680414.n4.nabble.com/math-Distributions-over-sample-spaces-other-than-R-tp3931349p3951273.html
> Sent from the Commons - Dev mailing list archive at Nabble.com.
>
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