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Re: st: unexpected -rbinomial- behaviour
From
Tirthankar Chakravarty <[email protected]>
To
[email protected]
Subject
Re: st: unexpected -rbinomial- behaviour
Date
Tue, 14 Sep 2010 13:34:15 -0700
Jeph,
The Stata function -rbinomial- is not defined for p=0. From
h rbinomial
rbinomial(n, p)
Domain n: 1 to 1e+11
Domain p: 1e-8 to 1-1e-8
Range: 0 to n
Your probabilistic statement about the degenerate Binomial
distribution is correct - the domain of the Binomial distribution is p
\in [0,1]. My guess would be that the p=/=0 condition is a limitation
of the simulation algorithm.
T
On Tue, Sep 14, 2010 at 12:54 PM, Jeph Herrin <[email protected]> wrote:
>
> Am I wrong to expect rbinomial(n,0) = 0?
>
> . di rbinomial(10,0)
> .
>
> I would think that if P(success)= 0, then E(successes)=0.
>
>
> Jeph
>
>
> *
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>
--
To every ω-consistent recursive class κ of formulae there correspond
recursive class signs r, such that neither v Gen r nor Neg(v Gen r)
belongs to Flg(κ) (where v is the free variable of r).
*
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