A dean of a business school wants to know if the proportion

A dean of a business school wants to know if the proportion of graduates who use statistical inference within the first year of graduation is greater than 0.6. A survey of 474 graduates resulted in 166 saying that they used statistical inference within the first year of graduation. Calculate the test statistic for the hypothesis specified above, to two decimal places.

Solution

Hypothesis Test:

n =474

Population proportion P =0.6

Sample Proportion p = 166 / 474 = 0.35

Test static :

z = (p - P) / sqrt[ P * ( 1 - P ) / n ]

= (0.35 - 0.6) / sqrt( 0.6 * ( 1 - 0.6 ) / 474)

= -11.11

P(X>0.6) = 1 - (~0) = ~1

Since P-value > 0.05

Insufficient evidence to come to a conclusion.