review-on-testing

This compares to 50 for the 35 44 group 53 for the 45

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: ccidents within the state could be the same as the age distribution of all U.S. drivers. Age Group U.S. Drivers Sample of 200 < 25 13.5% 42 25-44 41.4% 80 > 45 45.1% 78 Problem 2 - continued H0: p1 = 0.135, p2 = 0.414, p3 = 0.451 Ha: H0 fails to hold pi fi Ei < 25 13.5% 42 27.0 25-44 41.4% 80 82.8 > 45 45.1% 78 90.2 3 ( fi − Ei )2 χ =∑ Ei i=1 2 ( 42 − 27)2 (80 − 82.8)2 ( 78 − 90.2 )2 = + + 27 82.8 90.2 = 8.333 + 0.095 + 1.650 = 10.078 df = (3 − 1) = 2 Critical − value =5.991 Strong evidence against the null (signiRicant at the 5% level: reject H0 at 5%) Problem 3 In “good news – bad news” settings, researchers report that 83% of women in the 21- 34 age group say they prefer to hear the bad news _irst. This compares to 50% for the 35- 44 group, 53% for the 45- 54 group, and 70% for the 55- or- over group. Test at 1 % level whether news preference is independent of age group, assuming that the researchers worked with independent samples, each consisting of 100 women. Age \ Preference Bad News First Good News First 21-34 83 17 35-44 50 50 45-54 53 47 >55 70 30 Problem 3 - continued Observed counts: Age \ Preference Bad News First Good News First Total 21-34 83 17 100 35-44 50 50 100 45-54 53 47 100 >55 70 30 100 Total 256 144 400 Expected counts: Age \ Preference Bad News First Good News First Total 21-34 64 36 100 35-44 64 36 100 45-54 64 36 100 >55 64 36 100 Total...
View Full Document

This note was uploaded on 01/15/2014 for the course BUAD 310 taught by Professor Lv during the Fall '07 term at USC.

Ask a homework question - tutors are online