Regression methods were used to analyze the data from a study investigating the relationship between roadway surface temperature (x) and pavement deflection (y). summary quantities were n = 20.
∑yi=12.75,∑y2i=8.86,∑xi=1478,∑x2i=1 43,215.8,and∑xiyi=1083.67
. a. calculate the least squares estimates of the slope and intercept. graph the regression line. estimate σ^2. b. use the equation of the fitted line to predict what pavement deflection would be observed when the surface temperature is 85°f. c. what is the mean pavement deflection when the surface temperature is 90°f? d. what change in mean pavement deflection would be expected for a 1°f change in surface temperature?