Question

A traffic safety company publishes reports about motorcycle fatalities and helmet use. The distribution shows the proportions of fatalities by location of injury for motorcycle accidents. The data in the tables shows the location of injury and fatalities for 2102 riders not wearing a helmet. Proportion of fatalities by location of injury for motorcycle accidents Location of Injury Multiple locations Head Neck Thorax Abdomen/Spine Proportion 0.57 0.31 0.03 0.06 0.03 Location of injury and fatalities for 2102 riders not wearing a helmet Location of Injury Multiple locations Head Neck Thorax Abdomen/Spine Number 1036 920 38 83 25 Expected Write out the hypothesis. Calculate the expected counts and fill in the table above, do we meet the requirements to do the test? Find the test statistic. ?_0^2= Find the p-value p= What is the result of the hypothesis test (in the context of the question) if ?=.05?  

Answer 1

Ans:

Ho:Data fit the the speciifed distribution.

Ha:Data does not fit the the speciifed distribution.

	Observed(fo)	pi	Expected(fe)	(fo-fe)^2/fe
Multiple	1036	0.57	1198.14	21.94
Head	920	0.31	651.62	110.54
Neck	38	0.03	63.06	9.96
Thorax	83	0.06	126.12	14.74
spine	25	0.03	63.06	22.97
Total=	2102	1	2102	180.15

Test statistic:

chi square=180.15

df=5-1=40

p-value=CHIDIST(180.15,4)=0.0000

As,p-value<0.05,we reject the null hypothesis and we can conclude that above data does not fit the the speciifed distribution.