We sampled 100 men and 100 women and asked: ʺDo you think the environment is a major concern?ʺ Of those sampled, 67 women and 53 men responded that they believed it is. For the
Confidence interval procedure to work properly, what additional assumptions must be satisfied?
A)The population variances are equal.
B)Both samples were randomly and independently selected from their respective populations.
C)Both populations have approximate normal distributions.
D)All of the above are necessary.

Question

Quizplus · Accepted Answer

For the confidence interval procedure, especially in the context of proportions, the key assumption is that both samples were randomly and independently selected from their respective populations. This ensures that the samples are representative and that the estimates of proportions are unbiased. Assumptions about population variances or normal distributions are more relevant to means and not directly applicable to proportions.

We Sampled 100 Men and 100 Women and Asked: ʺDo