1. In a sample of 56 students, 32 said they plan to go to college
In a sample of 56 students, 32 said they plan to go to college. Find the 92% confidence interval of the proportion of students who plan to go to college.

2. Confidence Interval
Sample Size

3. Standard Error
It’s the estimated standard deviation of the statistic

4. An article by the right to die organization gave a proportion of physician’s who agree with their cause. I want to test their claim. I want to be within 0.05 with 95% confidence, how many must I sample? (Assume p = 0.5)

5. Why did I let p = 0. 5. If proportion is not given, use p = 0
Why did I let p = 0.5? If proportion is not given, use p = 0.5 because it’s including the most error. (Let n = 100) p q
0.1
0.9
0.2
0.8
0.3
0.7
0.4
0.6
0.5

6. A pollster wishes to estimate the proportion of U. S
A pollster wishes to estimate the proportion of U.S. voters who favor capital punishment. How large a sample is needed in order to be 95% confident that the sample proportion will not differ from the true proportion by more than 2%?

7. Homework
Worksheet