8 If you have been outside on a cold windy day, you have experienced wind chill. Wind chill is the temperature that our bodies feel when the wind blows on our skin on a cold day. When we experience wind chill, the temperature seems, to our bodies, to be colder than it actually is. Wind chill can be very dangerous. Meteorologists predict the temperature and wind chill to prepare people for how it feels outside. For example, people need to know the wind chill as they dress for the day. The table below displays wind chills for various wind speeds when the outside temperature is 15 F. Find the least-squares line y = a +-bx using the statistics in the following table. The formula for the slope and y-intercept of the least-squares line is given below. Statistics Mean Standard Deviation Correlation Wind Speed, x 17.5 9.35 -0.97 Wind Chill, y -11 14.09 slope: b = y-intercept: a = D - bx= B Use the least-squares line to predict the wind chill for the wind speeds listed below. Then calculate the residuals. x =.Wind Speed y = Wind Chill Predicted Value Residual (in mph) (in 'F) yy 5 12 10 -2 15 -11 20 -17 25 -22 30 -26 C Plot the residuals on the graph below. The x-value of each point is the explanatory variable and the y-value of each point is the corresponding residual. Residual IN W LUNHO 8 10 12 14 16 18 20 22 24 26 28 30 32 Wind Speed (mph) D Based on the residual plot, do you think the LSR line is an appropriate model? Explain