During a period of 11 years 805 of the people selected for g

During a period of 11 years 805 of the people selected for grand jury duty were sampled, and 63% of them were immigrants. Use the sample data to construct a 99% confidence interval estimate of the proportion of grand jury members who were immigrants. Given that among the people eligible for jury duty, 65.6% of them were immigrants, does it appear that the jury selection process was somehow biased against immigrants?

Solution

Test of p = 0.656 vs p not = 0.656

Sample X N Sample p 99% CI Z-Value P-Value
1 507 805 0.629814 (0.585977, 0.673650) -1.56 0.118

Using the normal approximation.

Since p value > 0.01 so we assume that there is no bias in our assumption