Mercury is a persistent and dispersive environmental contaminant found in many ecosystems around the world. When released as an industrial by-product, it often finds its way into aquatic systems where it can have deleterious effects on various avian and aquatic species. The accompanying data on blood mercury concentration (gg/g) for adult females near contaminated rivers in Virginia was read from a graph in the article ?"Mercury Exposure Effects the Reproductive Success of a Free-Living Terrestrial Songbird, the Carolina Wren" (The Auk, 2011: 759-769;? this is a publication of the American Ornithologists' Union). a. Determine the values of the sample mean and sample median and explain why they are different. b. Determine the value of the 10% trimmed mean and compare to the mean and median. c. By how much could the observation .20 be increased without impacting the value of the sample median?
Solution: Step 1: Here an experiment is conducted to find the effect of mercury in reproductive system of adult females. The have given data blood mercury concentration (gg/g) for adult females near contaminated rivers in Virginia. .20 .22 .25 .30 .34 .41 .55 .56 1.42 1.70 1.83 2.20 2.25 3.07 3.25