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- Problems will be added until the last class before the due date.
- No electronic submission unless explicitly allowed.
- Use your own words when answering questions. Copying from other sources (including textbooks, handouts, my blog) is strongly discouraged, because it often indicates you don't understand your answer.

- List 8 or more major problems associated with the spreadsheet from hell.
- Describe the difference between a continuous variable and a categorical variable, the advantages and/or disadvantages of categorizing a continuous variable.
- Describe what sensitivity analysis is and what scenarios a sensitivity analysis can lead to.
- Describe Simpson's paradox. A helpful reading is here.
- Nashville's December 2005 daily mean temperatures had mean 37.7 degrees (Fahrenheit) and standard deviation 7.0 degrees. The formula between Fahrenheit and Celcius is F = C * 9/5 + 32. Now, do you have enough information to get the mean and SD in Celcius? If yes, what are these? If no, what else do you need?
- A binary outcome can only take two possible values. Examples include coin flipping, sex of newborn babies, having a type of cancer or not, etc. We always can denote one outcome as "1" and the other as "0". Let the probability of having "1" be
*p*. Then 0 <*p*< 1 and*q*= 1 -*p*is the probability of having "0". Suppose there are*n*outcomes. The number*x*of outcome "1" can vary from 0 to*n*, with varying probabilities. These possible outcomes together with their associated probabilities are called a binomial distribution. The parameter*p*can be estimated by*x/n*. The coefficient of variation of this estimator is √[(1 -*p*)/(*np*)] x 100%.- Calculate the CV for
*n*= 10, 100, 1000 and*p*= .01, .05, .1, .3, .5. - Comment on how CV changes as
*n*increases with*p*fixed and as*p*changes with*n*fixed. - Suppose you want to estimate a cancer rate with accuracy measured as CV < 10%. What sample size do you need if the real rate is about 10%? What sample size do you need if the real rate is about 1%?

- Calculate the CV for

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