nerfhammer comments on binomial variance problem - Less Wrong

5 Post author: nerfhammer 06 April 2012 10:59PM

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Comment author: nerfhammer 08 April 2012 03:11:59AM 1 point [-]

What's the name of the principle that variance increases further from 50%?

Comment author: torekp 08 April 2012 02:07:51PM *  2 points [-]

Not having memorized the formula for variance in binomial distributions, but intuiting that said principle was true, was my weaker reason for concluding B.

More saliently, the problem statement contains the gratuitous information that boys are a majority in program A. It's Kahneman and Tversky, for FSM's sake; therefore this information is used to mislead. Therefore, B.

Comment author: othercriteria 08 April 2012 02:22:09PM 1 point [-]

Decreases! Note that there's zero variance when p = 0 versus non-zero variance when p = 0.5.

Comment author: RichardKennaway 08 April 2012 09:41:29AM 0 points [-]

No principle, just the fact that the variance of the binomial distribution is p(1-p), which peaks at p=0.5.