Stat 250, Section 003, Homework Assignment 7 (Due 3/24/99 in class)

• 1) Look at Assignment 6, Question 1 (the weather data) again. (7 points)
  
  
  • Calculate the residuals.
  • Draw at least two different residual plots (make clear what you plot on the x-axis each time) and state your conclusion.
  • List at least two lurking variables that could have an influence on the weather data but do not show up in this data set.
    
    
• 2) Look at Assignment 6, Question 4 (the photocopying paper) again. (7 points)
  
  
  • Calculate the residuals.
  • Draw at least two different residual plots (make clear what you plot on the x-axis each time) and state your conclusion. Does it make a difference if you know that Student 1 (Michelle) did the first 5 measurements and Student 2 (John) did the last 5 measurements?
  • List at least two lurking variables that could have an influence on the outcome of the measurements of the photocopying paper but do not show up in this data set.
    
    
• 3) Redesign this graphic from the Washington Post (once again this graphic has been reprinted in Wainer's Visual Revelations book) using a better statistical representation of the same data - and have a nice Spring Break :-) (6 points)