Stat 2000, Section 001, Homework Assignment 3 (Due 2/7/2000 in class)

• 0) Reading: Section 1.3
  
  
• 1) Please work on the following textbook exercises in Moore/McCabe:
  
  
  • Exercise 1.69, 1.70, 1.74, 1.76, 1.77 (1 Point each)
    
    
• 2) Answer questions 1.82, 1.84, and 1.87 in Moore/McCabe using the Table A in the textbook. Then check your results using the Web at http://davidmlane.com/hyperstat/z_table.html
  
  Given that you have access to the Web at all times, which method (use of the table or the Web application) do you prefer, e.g., which is easier to use. Explain. (10 points)
  
  By the way, the interactive Normal table at http://davidmlane.com/hyperstat/z_table.html is only one small part of an entire on-line introductory statistics book. If you ever need to look up some facts from an introductory statistics class but have no book at hand, you may find the answer in HyperStat at http://davidmlane.com/hyperstat/index.html.
  
  
• 3) In class, we have seen many types of static statistical graphics such as histograms, pie charts, or even micromaps. Since these graphics are printed on paper, there is obviously no possible interaction with these graphics. However, a medium such as the World Wide Web allows to interactively manipulate statistical graphics. It is to be expected that in the near future more and more statistical data, e.g., from Government agencies, can be interactively accessed and manipulated on the Web. One tool that allows such an interaction with statistical graphics on the Web is the Graphics Production Library (GPL) at http://www.monumental.com/dan_rope/gpl.
  
  (a) Describe in two or three sentences what the 4 `Sample Applets' (Barley, CPI, Unemployment, and TRI Release) are about. To make use of the full potential of these interactive graphics, you should also look at the Overview page at http://www.monumental.com/dan_rope/gpl/overview.html and apply these features to some of the interactive graphics. (6 points)
  
  Depending on the time of the day, type of computer, and connection to the Internet (modem or directly at USU), it can take a few minutes before something happens on your computer screen. If you cannot bring anything to show up on your screen, see me during my office hours and we can jointly look at these applets.
  
  (b) Now look at the Barley data at http://www.monumental.com/dan_rope/gpl/barley.html again. Compare the two years 1931 and 1932 (this can be done most easily if you grab one of the data columns with the mouse and move it into the other data column - if this does not work with your Web browser, look at the data very carefully...). Isn't there something strange in the data? Explain! (4 points)
  
  If you are interested in more details regarding the GPL, there is an article by Carr, Valliant and Rope about the GPL published in Vol. 7, No. 2, pages 19-26, in the Statistical Computing and Statistical Graphics Newsletter which is accessible at http://cm.bell-labs.com/cm/ms/who/cocteau/newsletter/index.html.