Determining the Sample Size

(sample size is based on margin of error, E, in confidence intervals) N = 1 / E2, for P near 0.5. or. N = (2 / E)2 P(1-P), for P near 0 or 1. N = (2S / E)2. where S is the standard deviation of the variable A confidence interval is a range of likely or plausible values of the population characteristic of interest. ................
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