Use the dataset AllCountries to examine the correlation between birth rate and life expectancy across countries of the world.
(a) Plot the data. Do birth rate and life expectancy appear to be linearly associated?
(b) From this dataset, can we conclude that the population correlation between birth rate and life expectancy is different from zero?
(c) Explain why inference is not necessary to answer part (b).
(d) For every percent increase in birth rate, how much does the predicted life expectancy of a country change?
(e) From this dataset, can we conclude that lowering the birth rate of a country will increase its life expectancy? Why or why not?