[R] Boxplot philosophy {was "Boxplot in R"}

[(Ted Harding)]

On 12-Jul-05 Spencer Graves wrote:
>         I'll bite:  How does one detect bimodalidty from a boxplot?
> 
>         spencer graves
> 
> Berton Gunter wrote:
> [...]
>> Finally, a tidbit for boxplot afficianados: how does one detect
>> bimodality from a boxplot?
>> 
>> -- Bert Gunter

Not definitively detectable of course, but certainly suspectable.

Hint: What is the relationship between the distances from the "median"
line to the extremes of the "box", and from the extremes of the "box"
to the ends of the "whiskers", in the case of a uniform distribution?



If that doesn't trigger it, then:

Hint:

  unimod<-rnorm(1000,0,sqrt(26))
  nomod<-sqrt(12*26)*runif(1000)
  boxplot(data.frame(cbind(unimod,nomod,bimod)))

Best wishes,
Ted.


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Date: 12-Jul-05                                       Time: 09:42:48
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