[R] sum(hist$density) == 2 ?!

[Jeff Newmiller]

Your clue is... density!

Probability density is not the same as probability... you have to multiply it by something before you can sum it.

Try typing

h

by itself and review your options.
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Sent from my phone. Please excuse my brevity.

Sam Steingold <sds at gnu.org> wrote:

>> x <- rnorm(1000)
>> h <- hist(x,plot=FALSE)
>> sum(h$density)
>[1] 2 ----------------------------- shouldn't it be 1?!
>
>> h <- hist(x,plot=FALSE, breaks=(-4:4))
>> sum(h$density)
>[1] 1  ----------------------------- now it's 1. why?!
>
>
>
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