solution

 

. Use the simple linear regression model with corn yield as the response variable and year as the explanatory variable to predict the corn yield for the year 2008, and give the 95% prediction interval. Also, use the multiple regression model where year and year2 are both explanatory variables to find another predicted value with the 95% interval. Explain why these two predicted values are so different. Compare the two prediction intervals. Explain why they differ in width even though the predicted values are similar? The actual yield for 2008 was 1539 bushels per acre. How well did your models predict this value?