alahonua

• alahonua 6 Feb 2013 19:05 UTC

  0 points

  on: How to avoid dy­ing in a car crash

  I know no one is likely to do this, but consider the safeguards taken by auto racing drivers. They are required to wear a helmet. For high speed driving helmets on all in the car would cut the death rate. That said, I doubt anyone will do this, as the inconvenience is great for a small payoff.

• alahonua 10 Jul 2020 17:21 UTC

  3 points

  on: Born as the sev­enth month dies …

  I don’t think you have the dependencies quite right, because you can actually use more of the information than you do above to restrict the population from which you draw.

  The real underlying population you should draw on seems to to be the population of fathers with exactly two children, of which one might be a boy born on Tuesday.

  p(a two boy family given one brother was born on Tuesday) = (p(one brother born on Tuesday in a in two-boy family)) (p(two boys in 2 person families)) /​ p(out of all two person families, having one be a boy born on Tuesday)

  which is if we say Tuesday birth is ¹⁄₇ and boy is ¹⁄₂,

  (2/​7) (1/​4) /​ (2/​14) = ¹⁄₂ so the Tuesday datum drops out.

• alahonua 11 Jul 2020 7:34 UTC

  1 point

  in reply to: Rudi C’s comment on: Born as the sev­enth month dies …

  This is correct, if you are excluding the case where both are boys both born on Tuesday. Otherwise you would not subtract p(A and B). But, you did not say only one, you said _at least_ one.

• alahonua 4 Nov 2020 6:47 UTC

  0 points

  on: Sleep­ing Ju­lia: Em­piri­cal sup­port for thirder ar­gu­ment in the Sleep­ing Beauty Problem

  I think that OP is confusing expected value with probability.

  The expected value formula is the probability of an event multiplied by the amount of times the event happens: (P(x) * n).

  This explains the P(B) = 1.5 the OP put above—he means the expectation is 1.5, because P(waking with any one coin flip result) = ¹⁄₂ and the times it occurs is 3.

  So the halfers believe the expectation is ¹⁄₂ for waking with heads and ¹⁄₂ for waking with tails.

  The thirders have the expected values right: 1 for waking with heads, 2 for waking with tails.

• alahonua 15 Nov 2020 19:20 UTC

  2 points

  on: Ex­am­ples of Measures

  Read this online classic paper about geometric measure theory, because it’s really entertaining:

  https://​​www.maths.ed.ac.uk/​​~tl/​​docs/​​Schanuel_Length_of_potato.pdf

• alahonua 31 Dec 2020 22:14 UTC

  1 point

  on: A Sim­plified Ver­sion of Per­spec­tive Solu­tion to the Sleep­ing Beauty Problem

  From a completely subjective view, there can be no single answer as to what day of the week it is. It is whatever weekday I decide it is. Who could gainsay it?

  As soon as we allow an objective view of what day of the week it is, we implicitly allow an over-ride of the subjective viewpoint by the objective one, and the ¹⁄₃ probability becomes the better choice.

• alahonua 3 Apr 2021 20:12 UTC

  1 point

  on: The Holy Algorithm

  Actually, the Easter 2021 date is in May for some Eastern communities: see

  https://​​www.thebostonpilot.com/​​article.asp?ID=189602