In a certain year, there were 80 days with measurable snowfall in Denver, and 63 days

Chapter 5, Problem 11

(choose chapter or problem)

In a certain year, there were 80 days with measurable snowfall in Denver, and 63 days with measurable snowfall in Chicago. A meteorologist computes

\((80+1) /(365+2)=0.22,(63+1) /(365+2)=0.17\), and proposes to compute a \(95 \%\) confidence interval for the difference between the proportions of snowy days in the two cities as follows:

\(0.22-0.17 \pm 1.96 \sqrt{\frac{(0.22)(0.78)}{367}+\frac{(0.17)(0.83)}{367}}\)

Is this a valid confidence interval? Explain.

Equation Transcription:

Text Transcription:

(80+1) /(365+2)=0.22,(63+1) /(365+2)=0.17

95 \%

0.22-0.17 \pm 1.96 \sqrt{\frac{(0.22)(0.78)}{367}+\frac{(0.17)(0.83)}{367}