Biology and Environmental Science
A study was conducted to investigate the relationship between asthma prevalence and annual rainfall in countries around the world. A random sample of 11 countries was obtained. The total annual rainfall (x, in mm) was recorded for each country, as well as the percentage of adults, 22-44 years old, treated for asthma (y). The following summary statistics were reported.
Sxx = 178,661
Syy = 49.2655
Sxy = 380.955
x‾ = 792.636
y‾ = 5.26
a. Find the estimated regression line.
b. Complete the ANOVA summary table, and conduct an F test for a significant regression. Does annual rainfall help to explain the variation in asthma prevalence? Justify your answer.
c. Find a 95% prediction interval for an observed asthma prevalence if the total annual rainfall is 1000 mm. Comment on anything odd about this interval.