Error in ppois function (PR#161)

[mh.smith@auckland.ac.nz]

Full_Name: Murray H Smith
Version: 0.63.3
OS: Windows NT
Submission from: (NULL) (130.216.5.57)


The ppois function is displaced by -0.5.
Try:

> ppois(-0.5,1)
[1] 0.3678794
> ppois(-0.51,1)
[1] 0
> ppois(0,1)
[1] 0.3678794

and

> par(mfrow=c(2,1))
> x<-seq(-1,5,0.01)
> plot(x,ppois(x,1),type="s",ylab="F(x)",main="Poisson CDF?")
> plot(x,pbinom(x,100,0.01),type="s",ylab="F(x)",main="Binomial CDF")


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