Question

In: Statistics and Probability

We are interested in comparing the percentage of females versus males who feel they are overweight....

  1. We are interested in comparing the percentage of females versus males who feel they are overweight. The following data was collected:
    1. What is the 95% confidence interval for the difference in proportion between women and men?
    2. What is the test statistic?

Male or Female

Total Surveyed

Number who feel they are overweight

Female

146

32

Male

84

15

Solutions

Expert Solution

For female, we have the sample size is n1= 146 , the number of favorable cases (number who feel they are overweight) is x1​=32, so then the sample proportion is

For male, we have the sample size is n2 = 84 , the number of favorable cases (number who feel they are overweight) is x2​=15, so then the sample proportion is

The value of the pooled proportion is computed as

a) We need to construct the 95% confidence interval for the difference between population proportions p1​−p2

The critical value for α=0.05 is zc​=1.96. The corresponding confidence interval is computed as shown below:

b)

Test Statistics

The z-statistic is computed as follows:


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