Question

A survey of 45 people was conducted to compare their self-reported height to their actual height. The difference between reported height and actual height was calculated. You're testing the claim that the mean difference is greater than 0.8. From the sample, the mean difference was 1.05, with a standard deviation of 0.76. Calculate the test statistic, rounded to two decimal places

Answer 1

Solution :

Given that :

= 0.8

= 1.05

= 0.76

n = 45

The null and alternative hypothesis is ,

H₀ :   = 0.8

H_a : > 0.8

This is the right tailed test .

Test statistic = z

= ( - ) / / n

= (1.05 - 0.8 ) / 0.76 / 45

= 2.21

The Test Statistic is = 2.21