Date: Feb 15, 2013 10:22 AM
Author: David C. Ullrich
Subject: Re: probability question about the dice game
On Thu, 14 Feb 2013 13:34:21 -0800 (PST), pepstein5@gmail.com wrote:

>On Thursday, February 14, 2013 6:05:23 PM UTC, Jussi Piitulainen wrote:

>> pepstein5@gmail.com writes:

>...

>>

>> >

>>

>> > David Ullrich is wrong. "X to Y" means that the probability of

>>

>> > winning is (X + Y)/Y.

>>

>>

>>

>> Which you later corrected to the reciprocal X/(X + Y); probabilities

>>

>> need to be between 0 and 1. But then it seems to me that Ullrich says

>>

>> the same, and that's also what I meant.

>>

>

>No, the reciprocal of (X + Y)/ Y is Y/(X + Y) which is what I should have said.

>Ullrich wrongly said X/(X + Y).

What??? I didn't say anything about probabilities! I said

something about odds, in particular terminology

used to express statements about odds.

Here's what I actually said, with a little context:

>> >>> from itertools import product

>> >>> die = {1,2,3,4,5,6}

>> >>> dice = set(product(die, die, die, die))

> > >>> sum(int(max(a,b) > max(c,d)) for a,b,c,d in dice)

>> 505

>> >>> sum(int(max(a,b) <= max(c,d)) for a,b,c,d in dice)

>> 791

>Cool.

>>I'd say her odds are 505 for and 791 against. I hope my gambling

>>vocabulary is not too far off.

>The terminology would be "her odds of winning are 505 to 791".

Nothing at all about probability. Look at the code I was referring

to: There are 505 equally likely cases leading to a win and 791

equally likely cases leading to a loss. That makes the odds of

winning precisely 505 to 795.

In particular, I said nothing at all about the math, my only

comment was about terminnology (this has something to do

with the fact that the OP's question was about terminolopgy).

It's beyond me what makes you think I said anything about

any probability being X/(X+Y).

And btw the terminology I gave _is_ perfectly standard.

To know that it's not you'd need to... never mind.

DU.