Question

1. Regression analysis was used to analyze the data from a study investigating the relationship between roadway surface temperature and pavement deflection. Using the data provided in table1, the goal

is to develop a simple linear regression model to estimate pavement deflection at any given surface temperature. Part a) Calculate the least squares estimates of the slope and intercept. Part b) Use the equation of the fitted line to predict what pavement deflection would be observed when the surface temperature is 85°F. Part c) Use the equation of the fitted line to find what change in mean pavement deflection would be expected for a 5°F change in surface temperature? Part d) Suppose that the surface temperature is 55°F, calculate the fitted value of pavement deflection and the corresponding residual. Part e) What percentage of variation in the data can be explained by this model?

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