In the publication “How Often Do Fishes ‘Run on Empty’?” (Ecology, Vol. 83, No 8, pp. 2145–2151), D. Arrington et al. examined almost 37,000 fish of 254 species from the waters of Africa, South and Central America, and North America to determine the percentage of fish with empty stomachs. The fish were classified as piscivores (fisheating), invertivores (invertibrate-eating), omnivores (anythingeating) and algivores/detritivores (eating algae and other organic matter). For those fish in African waters, the data on the WeissStats CD give the proportions of each species of fish with empty stomachs. At the 1% significance level, do the data provide sufficient evidence to conclude that a difference exists in the mean percentages of fish with empty stomachs among the four different types of feeders?
Use the technology of your choice to
a. Conduct a one-way ANOVA test on the data.
b. Interpret your results from part (a).
c. Decide whether presuming that the assumptions of normal populations and equal population standard deviations are met is reasonable.