Question

Can people tell the difference between a female nose and a male nose? Eight Caucasian males and eight Caucasian females posed for nose photos. The article states that none of the volunteers wore nose studs or had prominent nasal hair. Each person placed a black Lycra tube over his or her head in such a way that only the nose protruded through a hole in the material. Photos were then taken from three different angles: front view, three-quarter view, and profile. These photos were shown to a sample of undergraduate students. Each student in the sample was shown one of the nose photos and asked whether it was a photo of a male or a female; and the response was classified as either correct or incorrect. The accompanying table was constructed using summary values reported in the article. Is there evidence that the proportion of correct sex identifications differs for the three different nose views? Test the appropriate hypotheses using a .05 significance level. (Round your answer to two decimal places.) Sex ID View Front Profile Three-Quarter Correct 27 26 25 Incorrect 13 14 15

χ2 =

Answer 1

use Ti 84 calculator

Press 2nd button --> MATRIX --> EDIT

Enter the data in matrix A

Again

STAT --> TESTS -->

Observed : [A]

Expected : [B]

Press ENTER

we get

chi square test statistic = 0.22 (2 decimals)