What is the difference between N and n, P and p

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What is the difference between N and n, P and p
Message posted by Mike Webber on November 23, 2000 at 12:00 AM (ET)

In reading a number of the scientific journals, I notice that some of them write P<0.001 and others use p=0.001. The same applies to n and N. What is the difference (if any) between them? My son thinks (if he remembers rightly from school) that it may be to do with whether the analysis was taken from a compete population (N or P) or just from a sample of the data (n or p). Is this correct?

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Re: What is the difference between N and n, P and p
Message posted by Phil on November 23, 2000 at 12:00 AM (ET)

I would consider p and P the same thing (p-value).

N usually refers to the population size.

n usually refers to the sample size.

Re: What is the difference between N and n, P and p
Message posted by Holly on November 24, 2000 at 12:00 AM (ET)

Hi... N usually refers to a population size, while n refers to a sample size. Can also consider n to be the within-cell size, while N is the entire-sample size. P seems to be the same as p.

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