Question

Q2. Paul has conducted several polls to ask a class of business analytics students about their use of on-line learning material at different points in the delivery schedule of a virtual class. On the first poll, conducted in week 2, 45 students responded and of these 28 stated that they had viewed the video lectures and tried the examples prior to Paul’s tutorial. On a poll in week 6, 40 students responded of which half stated that they had used the on-line material in advance of the tutorial. Has the proportion of students changed significantly between these two polls? Construct appropriate confidence intervals and explain your reasoning.

Answer 1

The 95% confidence interval for the proportion of students between these two polls is between -0.088 and 0.332.

Since the confidence interval contains 0, we cannot conclude that the proportion of students between these two polls is not different.

p1	p2	pc
0.6222	0.5	0.5647	p (as decimal)
28/45	20/40	48/85	p (as fraction)
28.	20.	48.	X
45	40	85	n
	0.1222	difference
	0.	hypothesized difference
	0.1077	std. error
	1.13	z
	.2566	p-value (two-tailed)
	-0.088	confidence interval 95.% lower
	0.332	confidence interval 95.% upper
	0.21	margin of error