EU (European Union) countries report that 46% of their labor force is female. The United Nations wants to determine if the percentage of females in the U.S. labor force is
The same. Based on a sample of 500 employment records, representatives from the
United States Department of Labor find that the 95% confidence interval for the
Proportion of females in the U.S. labor force is .357 to .443. If the Department of Labor
Wishes to tighten its interval, they should
A) increase the confidence level.
B) decrease the sample size.
C) increase the sample size.
D) Both A and B
E) Both A and C

Question

Quizplus · Accepted Answer

To tighten a confidence interval, meaning to make it narrower, increasing the sample size is effective. A larger sample size reduces the standard error, leading to a narrower confidence interval. Increasing the confidence level would actually widen the interval, and decreasing the sample size would increase the margin of error, also widening the interval.

EU (European Union) Countries Report That 46% of Their Labor