#1
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Simple Variance Question
Can somebody calculate the variance for these two situations for me?
I'm a little rusty on my stats, and I think I'm going about it the wrong way Situation 1: Getting 1.5:1 on a coin flip Situation 2: Getting 6:1 on a single number, on a the roll of a die Please show all steps. |
#2
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Re: Simple Variance Question
V(x) = E(x^2) - E(x)^2
For the case of the die, E(x) = 3.5 E(x)^2 = 12.25 E(x^2) = 15.16667 V(x) = 2.91667 Coin flip (where 0 is one side, 1 is the other) E(x) = E(x^2) = 0.5 V(x) = 0.25 |
#3
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Re: Simple Variance Question
tyvm!
EDIT: errr... your values for E(x) are wrong, unless I'm missing something. |
#4
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Re: Simple Variance Question
FWIW: I have the EVs calculated as:
1: (1.5x-1x)/2 = 0.25x = E(x) 2: (6x-5x)/6 = 0.167x = E(x) |
#5
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Re: Simple Variance Question
[ QUOTE ]
Can somebody calculate the variance for these two situations for me? I'm a little rusty on my stats, and I think I'm going about it the wrong way Situation 1: Getting 1.5:1 on a coin flip Situation 2: Getting 6:1 on a single number, on a the roll of a die Please show all steps. [/ QUOTE ] Answered on Probability, where this problem belongs. djames is answering a different question, namely the variance of the number rolled on the die, and the variance of a coin flip where heads=1 and tails=0. The OP wants the variance of money won for a bet of size x. |
#6
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Re: Simple Variance Question
Thanks again, Bruce.
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#7
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Re: Simple Variance Question
Mods can feel free to delete this thread.
Apparently it's in the wrong forum. |
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