In a manufacturing process the assembly line speed (feet per minute) was thought to affect the number of defective parts found during the inspection process. to test this theory, managers devised a situation in which the same batch of parts was inspected visually at a variety of line speeds.
a. develop a scatter chart with line speed as the independent variable. what does the chart indicate about the relationship between line speed and the number of defective parts found?
b. use the data to develop an estimated regression equation that could be used to predict the number of defective parts found, given the line speed. what is the estimated regression model?
c. test whether each of the regression parameters beta subscript 0, beta subscript 0 , and beta subscript 1, beta subscript 1 , is equal to zero at 0.01 level of significance. what are the correct interpretations of the estimated regression parameters?
d. how much of the variation in the number of defective parts found for the sample data does the model you estimated in part (b) explain?