Assignment for Friday, March 24 (M 358K 06, Smith)

• Be sure to heed any comments given when your proposal was returned.
• Add any more considerations that you think of on your own or prompted by class reading and discussion.
• Bear in mind the following sentence given before the guidelines for sample sizes: "These are only rough guidelines; there may be more considerations depending on your specific question." For example, you may want or need to revise your sample sizes based on material in Chapters 5, 6 and 7. In particular:
• Look at the Rules of Thumb on pp. 342 and 344 to see if they are relevant.
• Also take into account (if appropriate) the Finite Population Correction discussed in class Monday, March 6.
  
•  Those of you who are estimating a proportion or a mean will need to form a confidence interval when analyzing your data, so need to think about what confidence level and margin of error you would like, and try to choose your sample size accordingly. 
• Those of you who will be comparing quantities need to do a significance test. You may want to think about the concept of "power" in Section 6.4.
• You may need to make further revisions in your sample size based on things we learn as we go along.
  
• Check out any major changes with me beforehand.
• Do not start gathering data until your proposal is approved by me. You might, however, want to do some preliminary data gathering to see if there are difficulties that you did not foresee, or to help you get a rought estimate of standard deviations to help estimate a desireable sample size.
• Remember that unexpected difficulties are common in data gathering and analysis. If they arise, try to think of possible remedies yourselves, but check them out with me before incorporating them in carrying out your project.

• The topic of power is especially relevant if you will be doing a hypothesis test in your project (for example, if you will be comparing means of two quantitative variables.)