Question

Question 5


Which of the following statements is incorrect?


(1) When only the sample size increases the CI estimate becomes narrower.

(2) When only the sample size decreases the CI estimate becomes wider.

(3) When only the confidence level increases the CI estimate becomes wider.

(4) When only the confidence level decreases the CI estimate becomes narrower.

(5) None of the above.


Question 6


The following intervals are the 90%, 95% and the 99% CI estimates for the population mean (in no

particular order):


(A) (196.06; 203.94)

(B) (194.82; 205.18)

(C) (196.70; 203.30)


Match the CI estimates to the appropriate CI level.


(1) A (90%), B (95%) and C (99%).

(2) A (95%), B (90%) and C (99%).

(3) A (99%), B (95%) and C (90%).

(4) A (90%), B (95%) and C (99%).

(5) A (95%), B (99%) and C (90%).

Answer 1

$Question\; 5\\ \text{The answer is (5) None of the above}\\ Question\; 6\\ \text{The answer is} (5) A(95\%), B(99\%), C(90\%)\\ \text{because the wider interval corresponds to}\\ \text{ the higher confidence level}$