[R] Round error?

[Peter Dalgaard]

Aurora Torrente <aurora at ebi.ac.uk> writes:

> Hi all,
> 
> I have tried to compute a p-value for a hypergeometric distribution as:
> 
> dhyper(x,k,l,n) + phyper(x,k,l,n,lower.tail=FALSE)
> 
> and sometimes obtained negative values.  Do you know if it is because
> a round error or am I doing something wrong?

Could you give us specific x,k,l,n where this happens, please. It
sounds like it shouldn't happen.

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark      Ph: (+45) 35327918
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