STAT question

Simulation Challenge 2 comes in two flavors: Sign Test (maximum of 50 points) or Wilcoxon Signed Rank test (maximum of 60 points).  You can do one or the other (NOT both). If you submit both, I will grade the WSR paper only.

Sign Test:

  • Generate a data set that satisfies the assumptions of the sign test.
  • Randomly select k% of observations to be 0
    • k = 5, 10, 25
    • n = 20, 100
  • What happens to the Type I error of the sign test under the zero fudge or jittering for all 6 combinations of k and n?
  • Compare the results to a paired t-test
  • Run the simulations, report results, and make a recommendation.

Wilcoxon Signed Rank Test:

  • Randomly select k% of differences to be 0.
    • k = 5, 10, 25
    • n = 20, 100
  • What happens to the Type I error of the WSR test under jittering, Pratt and Wilcoxon zero methods for all 6 combinations of k and n?
  • Compare the results to a paired t-test
  • Run the simulations, report results, and make a recommendation.

Some Notes:

On Monday, March 29, I will return papers with the following:

  • No iterations OR iterations much less than sample size
  • Screen shots of code or output (graphics OK)

Submission Guidelines

  • The results should be typed like a paper, with clearly defined sections for Introduction, Methods, Results, and Conclusions.
  • Your name must be at the top of the first page and on each successive page.
  • There should be an informative title (“Simulation Challenge 1” is not informative).
  • If you use MS Word to type homework, use an easy to read variable-width font (I like Ariel, Helvetica, and Geneva fonts) with a minimum of 12 point font.
  • Tables and graphs should be included in the body of the paper, as close as possible to the text that describes them.
  • Any graphics from R must be electronically cut-and-pasted in-line at the appropriate point of the write-up. Resize the graphics window to optimize the readability. I will show you how to do this in class.
  • Any mathematical notation must be provided with appropriate use of subscripts, superscripts and symbols. Use MS Equation or another equation editor if you submit your work in Word.
  • Captions for tables and graphs should be contain a description of the variable on the x-axis, a description of the variable on the y-axis, a description of any plotting symbols, and a brief summary of the point that the graph or table is meant to convey.
  • Code for the simulation challenge should be uploaded IN A SEPARATE FILE in plain text format. The code should be working code (no mistakes). Part of your grade is determined by how easily I can copy and paste your code from the text file and reproduce your results.
  • Maximum of 7 pages, including tables and graphs. There is no minimum. The code file is not included in the page count.

Everything does with R, and all codes needed. 

Data is required.