Question

You decide to test how accurate a certain TV station's weatherman is with his predictions. Over the course of several months, you note that there were 40 days where the weatherman said that there was a 60% chance of rain. It subsequently rained on 21 of those days. Evaluate the weathermans forecasting ability on the basis of this data The p-value of the hypothesis test is:______

Answer 1

0.483

Explanation:

Given that you decide to test how accurate a certain TV station's weatherman is with his predictions.

No of days = 40

weatherman prediction of proportion= 0.60

Observed proportion =
`(21)/(40) =0.525`

p difference = -0.075

`H_0: p = 0.60\\H_a: p \\eq 0.60`

(Two tailed test)

Assuming H0 to be true, std error =
`\sqrt{(pq)/(n) } \\=0.1069`

Test statistic Z = p difference/std error

= -0.7016

p value = 0.483