In some parts of the world, collisions with motor vehicles are a major source of mortality for some wildlife species. For example, a major cause of the decline of the koala population in Queensland, Australia, is koala death from their collisions with vehicles. Ellis et al. (2016) investigated whether animal-vehicle collisions were more common in months with less daylight (darkness lasted 3.3 h longer in the winter than in the summer).

For each month of a single year, they tracked both the average number of hours of darkness and the number of wildlife-vehicle incidents. Their data are below.

a. Plot the relationship between hours of darkness and number of wildlifevehicle incidents. Do these data fit the assumptions of correlation?

b. What is the correlation between these two variables in the sample?

c. What is the 95% confidence interval for the population correlation?

Transcribed Image Text:

Average daily darkness (h) 10.210.2 10.410.4 10.610.6 11 11 11.211.2 11.811.8. 12.312.3 12.512.5 12.812.8 13.213.2 13.313.3 13.513.5 Wildlife-vehicle incidents 76 76 81 81 96 96 66 66 114114 93 93 132132 120120 135135 141141 152152 145145