Determine Required Sample Size. If the population is N then the corrected sample size should be 186N N185. Sigma σ is provided and the significance level is specified we can compute the minimum required sample size that will lead to a margin of error less than or equal to the one specified by using the following formula.
N ge left frac z_c sigma Eright2 n E zc. Assume that the result is a sample size beyond what you can obtain. Thus 186 sample size arrived at should be corrected adjusted for finite population.
In 2001 a Gallup poll surveyed 1016 households in the US about their pets.
ANOVA fixed effects omnibus one-way small effect size alpha 05 beta 2 3 groups. This gives a sample size of 367. Determine the minimum sample size needed to construct a 99 confidence interval for the population mean. A confidence level of 90 is judged to be appropriate.
