Question: Late bloomers? Japanese cherry trees tend to blossom early when spring weather is warm and later when spring weather is cool. Here are some data on the average March temperature (in °C) and the day in April when the first cherry blossom appeared over a 24-year period:
(a) Make a well-labeled scatterplot that's suitable for predicting when the cherry trees will bloom from the temperature. Which variable did you choose as the explanatory variable? Explain.
(b) Use technology to calculate the correlation and the equation of the least-squares regression line. Interpret the correlation, slope, and y intercept of the line in this setting.
(c) Suppose that the average March temperature this year was 8.2°C. Would you be willing to use the equation in part (b) to predict the date of first bloom? Explain.
(d) Calculate and interpret the residual for the year when the average March temperature was 4.5°C. Show your work.
(e) Use technology to help construct a residual plot. Describe what you see.