## Fall 2014: HS 550

#### Homework 1

• Problem 1: Use the World Country Ranking dataset and SOCR Charts to generate a scatter plot, a line plot, a dot plot, a boxplot, a histogram plot and a pie chart for some of the variables (ED, Edu, HI, QOL, PE, OA, Relig).
• Problem 2: Using R and SOCR, generate 100 random observations from uniform(-1,1), normal(0,1) and exponential(1) distributions. Then Use the SOCR QQ Data-Data Plot to compare the paired samples, i.e., for each distribution, plot the quantiles of the R-generated sample against the SOCR generated sample. What do you expect and what do you see? Explain.
• Problem 3: Below is the data of 400 Melanoma (skin cancer) Patients by Type and Site.
 Type Site Totals Head and Neck Trunk Extremities Hutchinson's melanomic freckle 22 2 10 34 Superficial 16 54 115 185 Nodular 19 33 73 125 Indeterminant 11 17 28 56 Column Totals 68 106 226 400
• If we select one out of the 400 patients in the study, what is the probability that the cancer is on the extremities given that it is a type of nodular: P = P(Extremities | Nodular)?
• What is the probability that for a randomly chosen patient the cancer type is Superficial given that it appears on the Trunk?
• Problem 4: Using the smoking and heart attack contingency table below, compute the odds ratio (OR) of heart attack relative to smoking, and compute the CI of the OR.

 Heart Attack (HA) Total Yes No Smoking (S) Yes 33 18 51 No 167 182 349 Total 200 200 400

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