Example: Manatees & Motorboats

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This example examines the residuals between data points and a linear fit. You will have the opportunity to vary the parameters (intercept, slope) for a line passing through the data set and see the resulting sum of the squares of the residuals. The notions of correlation and causality in a data set are compared.

It has been conjectured that there is a relationship between the number of manatees dying in Florida waters and the use of motorboats in those waters. The following table shows number of manatee deaths by motorboats and number of motorboats registered in Florida during the period from 1977 to 1990.

For more information on manatees, visit the pages of Jacksonville University's Manatee Research Center. Current data on manatee deaths is available from the Florida Marine Research Institute.