Let the p.m.f. of M be defined by f(x)=x/8,x=1,3,4.

Thread starter morr485
Start date Aug 28, 2009

AI Thread Summary

The probability mass function (p.m.f.) of M is defined as f(x) = x/8 for x = 1, 3, 4, with probabilities P(M=1) = 1/8, P(M=3) = 3/8, and P(M=4) = 4/8, which sum to 1. The mean of M, or E(M), can be computed using the definition of expected value. To find the mean, multiply each value by its probability and sum the results. This p.m.f. is not binomial, although E(M) is a similar concept. The discussion clarifies the relationship between the mean and the p.m.f. without equating it to a binomial distribution.

Aug 28, 2009

morr485

Let the p.m.f. of M be defined by f(x)=x/8,x=1,3,4. What is the mean of M?
Is this the same an E(M) of a binomial?

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Aug 28, 2009

g_edgar

I guess we have P(M=1)=1/8, P(M=3)=3/8 and P(M=4) = 4/8. These add to 1.
So the mean is ... what? Do the computation from the definition.
Yes, this is another name for E(M), but it is not binomial.

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