>>>>> David Winsemius <dwinsemius at comcast.net>
>>>>> on Thu, 7 May 2015 12:10:25 -0700 writes:
> On May 6, 2015, at 7:00 PM, Benjamin Tyner wrote:
>> Hi
>>
>> I'm wondering if anyone is aware of an R package implementing
(i.e.,
>> providing a pdf, cdf, and/or quantile function) for the continuous
>> binomial distribution? Specifically the one characterized here:
>>
>>
http://www2.math.uni-paderborn.de/fileadmin/Mathematik/AG-Indlekofer/Workshop/Satellite_meeting/ilenko.pdf
>>
>> Figured I would check here first, before attempting to code it up
myself.
> I found that reading the ArXiv version of that material was easier to
understand:
> http://arxiv.org/abs/1303.5990
> zipfR package has an implementation of the incomplete beta function
that might make some of the coding of the pdf and cdf more simple.
Well.
To: David Winsemius <dwinsemius at comcast.net>
Subject: Re: [R] package implementing continuous binomial?
In-Reply-To: <5425134B-6AA1-4246-BCD4-D4BE4BE2391B at comcast.net>
References: <554AC75A.8070708 at gmail.com>
<5425134B-6AA1-4246-BCD4-D4BE4BE2391B at comcast.net>
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Reply-To: Martin Maechler <maechler at stat.math.ethz.ch>
CC: maechler
--text follows this line--
Dear David,
>>>>> David Winsemius <dwinsemius at comcast.net>
>>>>> on Thu, 7 May 2015 12:10:25 -0700 writes:
> On May 6, 2015, at 7:00 PM, Benjamin Tyner wrote:
>> Hi
>>
>> I'm wondering if anyone is aware of an R package implementing
(i.e.,
>> providing a pdf, cdf, and/or quantile function) for the continuous
>> binomial distribution? Specifically the one characterized here:
>>
>>
http://www2.math.uni-paderborn.de/fileadmin/Mathematik/AG-Indlekofer/Workshop/Satellite_meeting/ilenko.pdf
>>
>> Figured I would check here first, before attempting to code it up
myself.
> I found that reading the ArXiv version of that material was easier to
understand:
> http://arxiv.org/abs/1303.5990
> zipfR package has an implementation of the incomplete beta function
that might make some of the coding of the pdf and cdf more simple.
> Searching done with Graves' very useful utility package:
> library('sos')
> findFn("incomplete beta function")
Hmm... R's pbeta() function is a pretty good implementation
of the incomplete beta function ... as is tries to say on its
help page.
If you look closely, these functions (for incomplete gamma,
incomplete beta, and their inverses) are simple wrappers to
pgamma() and qgamma() --- sometimes "regularizing" and sometimes
not -- where regularization is simply a multiplication/division
with gamma() or beta().
I wonder why you did not find R's help page about the beta distribution
{ -> functions dgamma, pgamma, qgamma, rgamma }
which does mention the "incomplete beta function" prominently.
I don't think Benjamin should use the zipfR package just for
these functions [and even the zipfR package help page on these
can be read as saying so .. ]
In the end I wonder if the "continuous Binomial" is not just a
version of the good old Beta distribution... as indeed the
Binomial and the Beta are related in the same way
that the Gamma and the Poisson are.
Martin Maechler
ETH Zurich
> (I did't think that doing a search on "continuous
Binomial" was likely to be helpful, but I tried it anyway and did not find
any functions named "continuous binomial" in their help page titles.)
> --
> David Winsemius
> Alameda, CA, USA