Re: Binomial distribution

Why not upload the image here?

Re: Binomial distribution

Hey KarlssonKK.

The asymptotic distribution results are such that (X - E[X])/SQRT(Var(X)) ~ N(0,1).

So to start off, can you calculate the mean and the variance of your distribution? Using this result, can you then construct a corrected interval (remember that for a binomial, you should find a probability corresponding to 64.5 and not 64 because of the disjoint nature of the binomial)?

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Re: Binomial distribution

Re: Binomial distribution

Quote:

Originally Posted by

**chiro** Hey KarlssonKK.

The asymptotic distribution results are such that (X - E[X])/SQRT(Var(X)) ~ N(0,1).

So to start off, can you calculate the mean and the variance of your distribution? Using this result, can you then construct a corrected interval (remember that for a binomial, you should find a probability corresponding to 64.5 and not 64 because of the disjoint nature of the binomial)?

Yes I can calculate the variance but I'm note sure thats the way to go, but if I do, what do I do then?

and what do you mean by finding a propability corresponding to 64,5? I understand that I should not include 65 since it is

<60 and not =<60.

Re: Binomial distribution

Quote:

Originally Posted by

**MaxJasper**

How did you calculate this?

Re: Binomial distribution

Re: Binomial distribution

The **reason** you should calculate the standard deviation (and mean) is that a binomial distribution with large number of 'trials' can be approximated by the normal distribution with the same mean and standard deviation.

Re: Binomial distribution

Quote:

Originally Posted by

**chiro** you should find a probability corresponding to 64.5 and not 64 because of the disjoint nature of the binomial)?

I think that should be 65.5.

Using the binomial calculation above we get about 0.1629.

Using the normal approximation we get about 0.1631.

Re: Binomial distribution

If the problem is to find the probability that the number of "successes" is 64, then you should use the normal approximation to find the probability that x is between 64.5 and 65.5.

Re: Binomial distribution

Yes it should have been 65.5.