[R] hist and truehist

[Peter Dalgaard]

Gregor GORJANC <gregor.gorjanc at bfro.uni-lj.si> writes:

> Hello!
> 
> Up to now I have been using hist() to display the distributions.
> Howevere, I noteiced strange numbers on y (vertical) axis, if I used
> probability = T or freq = F option. I thought it is a bug and launched
> the R-bug system and found some posts on that matter. Brian Ripley
> responded to one, that one should look at truehist() for that. Ok I
> can use truehist() if I want to see the ratios or probabilities, but
> what is then the "density or probability" in hist()?

...

> truehist(mydata) # looks OK

And truehist(mydata, h=.5)?

It is a density estimate. The sum of the bar _areas_ should be 1. 

> sum(x$intensities * .5)
[1] 0.9999998


-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
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