Question

Listed below are annual data for various years. The data are weights ( metric tons) of imported lemons and car crash fatality rates per 100,000 population. Construct a scatterplot, find the value of the linear correlation coefficient 'r' and find the P- value using significance level 0.05. Is there sufficient evidence to conclude that there is a linear correlation between lemon imports and crash fatality rates? Do the results suggest that imported lemons cause car fatalities?

Lemon imports 232 266 359 480 530

Crash fatality rate 15.8 15.7 15.5 15.3 14.8

Answer 1

By using excel we can solve this question easily.

We have to find a scatter plot

-First, enter all data into excel

Select all data ----------> Click on Insert --------> Scatter ------->Click on first graph

We get

The linear correlation = r = - 0.9455

( Using excel =CORREL(Lemon imports, Crash fatality rate))

Claim: There is a linear correlation between lemon imports and crash fatality rates.

The null and alternative hypothesis

Level of significance = 0.05

Test statistic is

Sample size = n = 5

Degrees of freedom = n - 2 = 5 - 2 = 3

P-value = 2*P(T < - 5.028) = 2*0.0076 = 0.0152

P-value < 0.05 we reject null hypothesis.

Conclusion: There is a linear relationship between lemon imports and crash fatality rates.

Yes, the results suggest that imported lemons cause car fatalities.