Stat 250, Section 003, Extra Credit (Due 5/5/99 in class)

• 1) We have seen several plots (e.g., the Weider empire) so far that provide only very little of the information one would like to have about the underlying topic. Can you find similar plots in newspapers, magazines, on the Web, or even your textbooks? If so, then state questions you would like to have answered about the provided data but no such answers have been given in the plot, the accompanying caption or the main text where the plot is coming from. Indicate where the plot has been found and turn in a photocopy (or printout) of this plot and the accompanying text.
  
  
• 2) You have to use a Web browser to answer this question. Use a search engine such as http://www.excite.com/, http://www.lycos.com/, or http://www.yahoo.com/ and search for Webpages that relate to statistics and your major subject.
  
  On top of these pages you usually have a box where you can type in the keywords you are looking for. You can type in a single keyword, multiple keywords separated by a blanc, e.g., kw1 kw2 kw3 (in this case, the search engine will look for kw1 or kw2 or kw3), and multiple keywords with a leading +, e.g., +kw1 +kw2 +kw3 (in this case, the search engine will look for kw1 and kw2 and kw3). If you try "text" where text appears in double quotes and may be a longer sentence, you should find pages that contain these words in exactly the same order (but eventually with a few other words inbetween).
  
  As an example, I used http://www.excite.com/ on 4/9/99 and tried
  • +Statistics +Nursing (14647 hits)
  • +Statistics +Nursing +Software (3116 hits)
  • +Statistics +Poetry (6262 hits)
  • "Government Statistics" (2135 hits)
  
  As an answer to this question
  • i) indicate which search engine you used and which keywords you have searched,
  • ii) indicate 3 to 5 interesting Web addresses that are related to statistics and your major subject (please list this subject again on your answer sheet), and
  • iii) visit the pages from ii) above and provide a 2 or 3 sentence summary on what this page is about, e.g., providing particular data, data about this subject (income distribution, number of people with this profession), information on (downloadable) software particularly helpful in this subject, information on new statistical methodology for this subject, etc.
  
  
• 3) We have seen many small examples where JAVA applets have been used, e.g., to demonstrate the effect of different bin widths for histograms. The page http://www.stat.sc.edu/~west/javahtml/Histogram.html contains instructions how to modify this example and how to include your own data. Can you create a Webpage that makes use of this particular JAVA applet and gives an introduction to some of our class data set(s) and allows to look at the effect of a varying histogram for this data. It would be ideal if you could create a page that contains two histograms (displaying payroll and wins) as well as the regression applet from http://www.stat.sc.edu/~west/javahtml/Regression.html.
  
  As an answer to this question, just provide the URL where your created Web page can be found.
  
  
• 4) We did not introduce any statistical package in this class however many of you used statistical software for your homeworks. The aim of this question is to explore an unknown package, http://statlets.com, and get it to work. You have to select 'Internet Access' first, then the appropriate 'Menu Version' with respect to the capabilities of your Web browser. Also, read carefully through the on-line documentation and use a small data set to get familiar with the program first.
  
  Move on one step and use the full "Cost of Victory: Payroll/Win" data set. This data is available in electronic form at http://www.galaxy.gmu.edu/~symanzik/teaching/1999_stat250/victories.dat. Incorporate this data into http://statlets.com (using the 'Clipboard' option might be the easiest way to do so) and do a full statistical analysis (graphical and numerical).
  
  As an answer to this question, you can turn in printouts or write down main results from the screen (make sure to maintain rounding and classes used for drawings in exactly the way http://statlets.com does so I can see you really used this package). Alternatively, you can indicate which steps (what is the exact labeling of each button you selected at a given time) you conducted to achieve a particular result. If printing does not work for you, you should at least copy and paste numerical results (what does the 'Statistical Interpreter' indicate) from a http://statlets.com window into your text processor window and print this text later from a different computer. You can restrict yourself to those statistical features known from class - you do not have to explore every feature of this software package.
  
  You cannot use any other package to answer this question! Also note that http://statlets.com does not run on older machines and typically does work better under Internet Explorer than under Netscape. Plan on enough time to work on this question. If you cannot find an appropriate computer, come to my office during my office hours - there are several computers you can use for this purpose.
  
  
• 5) The following Web page from the Colorado Department of Regulatory Agencies (DORA) describes, among others, the number of registered nurses (RN) from 1/91 to 1/97:
  http://www.dora.state.co.us/Nursing/Nur0017.htm
  
  Do a complete statistical analysis (numerical and graphical) of the RN data set and answer the following questions:
  
  
  • Based on the statistical model you have fitted, how many registered nurses does your model predict for 7/95 and for 1/99, respectively? Do these numbers make any sense?
  • Assess the quality of the statistical model you have fitted.
  • Is there anything strange in the RN data?
  • Is there any (strong) relationship between registered nurses (RN) and nurse aides (NSE Aides)?
  • Provide a written summary (about one half page) that includes all your previous findings.
  
  You can calculate your results by hand, use any statistical package you like, or obviously use http://statlets.com that has been introduced in question 4) above. This question will be graded with respect to correctness and completeness (did you do all the steps that make up a full analysis).