This exercise is extremely tedious and hardly ever

works out the way it ought to, mostly because not

many people have the patience to draw an infinite

number of even very small samples. However,

if you want a more concrete and tangible understanding

of sampling distributions and the two

theorems presented in this chapter, then this exercise

may have a significant payoff. At the end of

this problem are listed the ages of a population of

college students (N 50). By a random method

(such as a table of random numbers), draw at least

50 samples of size 2 (that is, 50 pairs of cases), compute

a mean for each sample, and plot the means

on a frequency polygon. (Incidentally, this exercise

will work better if you draw 100 or 200

samples and/or use larger samples than N 2.)

a. The curve youve just produced is a sampling

distribution. Observe its shape; after 50

samples, it should be approaching normality.

What is your estimate of the population mean

(m) based on the shape of the curve?

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