Refer to Original Source 20 on the companion website, “Organophosphorus pesticide exposure of urban and suburban preschool children with organic and conventional diets.” In Table 4 on page 381, information is presented for estimated dose levels of various pesticides for children who eat organic versus conventional produce. Find the data for malathion. Assume the minimum exposure for both groups is zero. Otherwise, all of the information you need for a five- number summary is provided. (The percentiles are the values with that percent of the data at or below the value. For instance, the median is the 50th percentile.)
a. Create a five-number summary for the malathion exposure values for each group (organic and conventional).
b. Construct side-by-side skeletal boxplots for the malathion exposure values for the two groups. Write a few sentences comparing them.
c. Notice that in each case the mean is higher than the median. Explain why this is the case.