Physical Sciences Researchers at a marine institute investigated the relationship between the…
Physical Sciences Researchers at a marine institute investigated the relationship between the dissolved barium concentration and the silicate/nitrate ratio in the North Pacific Ocean. The silicate/nitrate ratio (x) and the dissolved barium concentration (y, in nmol/kg) were measured at randomly selected locations.
a. Find the estimated regression line, and compute the residuals.
b. Conduct an F test for a significant regression. Use a significance level of 0.01.
c. Carefully sketch a normal probability plot of the residuals and a plot of the residuals versus the predictor variable.
d. Do these graphs provide any evidence that the simple linear regression assumptions are invalid? Justify your answer.