Question

Your professor has noticed that some students on campus tend to ignore traffic rules when riding on bicycles. Suppose we were to monitor 6 bike-riding students on campus while recording percentage of time spent obeying traffic laws (higher percentage = more obeying the law) and number of near misses (close calls) with traffic/pedestrians. Would we find that there is a correlation between law abiding bike riding and near misses (alpha = .05)? Use a two-tailed test.

Percent Time Obeying Law	Near Misses
100	0
91	3
78	2
78	7
72	6
68	12

What should we conclude based on these data?

		Retain the Null Hypothesis
		Prove the Research Hypothesis
		Prove the Null Hypothesis
		Reject the Null Hypothesis

Answer 1

null hypothesis: Ho:               ρ		=	0
Alternate Hypothesis: Ha: ρ		≠	0
0.05 level,two tail test and n-2= 4 df, critical t=			2.7764
Decision rule: reject Ho if absolute value of test statistic |t|>2.776
correlation coefficient r=		Sxy/(√Sxx*Syy) =	-0.8187
test stat t=	r*(√(n-2)/(1-r2))=	-2.8516

since test statistic falls in rejection region we reject null hypothesis

Reject the Null Hypothesis