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location Bellevue, WA
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seen Sep 18 '13 at 7:51

Oct
31
awarded  Popular Question
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14
awarded  Good Question
Jul
13
comment Will a point moving on a sphere always at an angle x (0 deg. < x < 90 deg.) to the “equator” reach a “pole”?
Yes, I see. Thanks.
Jul
13
accepted Will a point moving on a sphere always at an angle x (0 deg. < x < 90 deg.) to the “equator” reach a “pole”?
Jul
13
comment Will a point moving on a sphere always at an angle x (0 deg. < x < 90 deg.) to the “equator” reach a “pole”?
The point moving at a constant speed was not built into my question. The answer to my question remains "yes" even if the speed isn't constant. It could even stop repeatedly for finite lengths of time, no? Just wanting to touch all the bases....
Jul
13
revised Will a point moving on a sphere always at an angle x (0 deg. < x < 90 deg.) to the “equator” reach a “pole”?
Modifying question in response to Martin Argerami's comment.
Jul
13
asked Will a point moving on a sphere always at an angle x (0 deg. < x < 90 deg.) to the “equator” reach a “pole”?
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awarded  Famous Question
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31
awarded  Yearling
Sep
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awarded  Notable Question
May
23
awarded  Nice Question
Mar
22
awarded  Popular Question
Dec
27
accepted In a family with two children, what are the chances, if one of the children is a girl, that both children are girls?
Dec
27
comment In a family with two children, what are the chances, if one of the children is a girl, that both children are girls?
(continued) I assumed this because to interpret "one of my children is a girl" as meaning "exactly one of my children is a girl" would destroy the problem/puzzle in that the answer would be too obviously zero. Also, because I had first seen the question in a book about randomness and probability, I was already in math English mode.
Dec
27
comment In a family with two children, what are the chances, if one of the children is a girl, that both children are girls?
(continued) I'd award you the 100 bounty points for the clarity of your explanation of the mathematics, if you hadn't added your idea that "Probability puzzles like the one you're asking about rely on these differences of English meaning, rather than on any logical or mathematical problem. In that sense, they aren't really puzzles, they're just tricks." In my case I wasn't tricked -- I immediately assumed that "one of my children is a girl" meant that "at least one of my children is a girl".
Dec
27
comment In a family with two children, what are the chances, if one of the children is a girl, that both children are girls?
I now, at last, agree that the correct answer is 1/3. (See my question "2 slightly different situations in which 2 coins are tossed. Does the knowledge of an observer effect the probabilities of the outcomes?" at goo.gl/yyOlK and my comment beginning with "@all: It suddenly hit me that I didn't need that truthful observer.", about half way down the page, under Willie Wong's answer.)
Dec
27
comment 2 slightly different situations in which 2 coins are tossed. Does the knowledge of an observer effect the probabilities of the outcomes?
for or against anyone's answer, but I may have accidentally pressed the left button of my mouse when the cursor was over an arrow. But if you make even a tiny edit to your answer I'll be able to give you an up vote.
Dec
27
comment 2 slightly different situations in which 2 coins are tossed. Does the knowledge of an observer effect the probabilities of the outcomes?
@Rahul: Please read my long comment (posted some 3 hours before your last, beginning with "@all: It suddenly hit me that I didn't need that truthful observer." and tell me what you think. I put it under Willie Wong's answer because I wanted to credit him belatedly with the first (and good) answer. I also want to give you an "up" vote for yours (really for sticking with me), but apparently I screwed up at some time before. When I click the up-arrow by your answer I'm told I've already voted and can do nothing unless the answer is edited. I'm sure that I didn't intentionally do any voting at all
Dec
26
accepted 2 slightly different situations in which 2 coins are tossed. Does the knowledge of an observer effect the probabilities of the outcomes?
Dec
26
comment 2 slightly different situations in which 2 coins are tossed. Does the knowledge of an observer effect the probabilities of the outcomes?
at-least-one-heads outcomes. I would continue until I had tallied 100 at-least-one-heads outcomes. The result, if anyone's curious, was 70 1-heads, 30 2-heads. As for situation A, its equivalence could be tossing the coins together but only tallying the number of heads (1 or 2) of those outcomes where the nearest coin was heads. An outcome where the nearest coin was tails would be ignored. But of course this is equivalent to just tossing one coin and considering the probability of heads (1/2).