Talk:Bernoulli distribution

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f(0.5), for example, is not zero

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[edit] tacticity question

does anyone have an idea if Bernoullian probability on the tacticity page is covered in wikipedia and if so where? possibly redirect? thanks in advance V8rik 23:07, 2 August 2005 (UTC)

[edit] mode error

i think the mode of the Bernoulli distribution should be zero if p<0.5, should be 1 if p>0.5, and should be equal to "0 and 1" when p=0.5.

Thanks.

[edit] Bernoulli kurtosis excess is actually kurtosis?

The equation given for 'kurtosis excess' is correct.

http://mathworld.wolfram.com/BernoulliDistribution.html gives this formula for the excess but describes it as the kurtosis rather than kurtosis excess as elsewhere.

Although the custom in Wikipedia is to use the term kurtosis for the kurtosis_excess, it is important to avoid confusion.

IMO it would be better to give BOTH in ALL distribution tables to reduce the risk of any more similar muddles.

And to say true kurtosis for kurtosis and excess kurtosis in the text.

BUT I also note that http://mathworld.wolfram.com/Kurtosis.html gives a MUCH simpler formula

 1/(1-p) + 1/p - 6

and this would seem preferable because it is simpler and makes obvious the effect of changing p.

A formula for the 'true' kurtosis is

  1/(1-p) + 1/p - 3

(The kurtosis excess formula given currently is just the binomial with n = 1, and can be simplified).

Paul A Bristow 14:45, 13 December 2006 (UTC) Paul A Bristow

The article says that the Bernoulli distribution with p = 1 / 2 has a lower kurtosis than any other probability distribution. But in fact its kurtosis of − 2 is the same as that of any distribution that takes two distinct values, each with probability 1 / 2. Fathead99 (talk) 18:23, 5 March 2008 (UTC)

[edit] derivations

I hope somebody could help me in finding derivations or how to derive the skewness and kurtosis, even link to other sites will be much appreciated. —Preceding unsigned comment added by Student29 (talk • contribs) 19:31, 16 January 2008 (UTC)


[edit] Why no median?

Is there any particular reason why the Bernoulli distribution lacks a defined median? I would think that the median is 1 if p > 0.5, 0 if p < 0.5, 0.5 if p = 0.5. 169.232.78.24 (talk) —Preceding comment was added at 21:24, 7 February 2008 (UTC)

I think the median is 1 if p > 0.5 and 0 if p < 0.5, but it does not exist of p = 0.5. -- NaBUru38 (talk) 16:23, 11 February 2008 (UTC)