# quiz 2.docx - Question 1 3.125 out of 3.125 points Correct...

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Question 1 3.125 out of 3.125 points Correct For a linear regression b1 is the estimated y-intercept, and b0 is the estimated slope of the regression line.
Question 2 3.125 out of 3.125 points Correct The decision rule for a Wilcoxon signed-rank test is always to reject H0 if W is greater than or equal to the critical value.
Question 3 3.125 out of 3.125 points Correct Hypothesis testing on samples with fewer than 30 participants can be carried out by using the t-value for the corresponding level of significance in place of the z value when setting up the decision rule.
Question 4
3.125 out of 3.125 points Correct The Cochran–Mantel–Haenszel method is a technique that generates an estimate of an association between a risk factor or exposure and an outcome accounting for confounding.
Question 5 3.125 out of 3.125 points Correct Type I error occurs when H0 is correct but H0 is rejected.
Question 6 0 out of 3.125 points Incorrect The degrees of freedom in a chi-squared test equal to the number of participants in the test minus 1.
Question 7 0 out of 3.125 points Incorrect
The test statistic for a Wilcoxon signed-rank test is always the smaller of the number of the total number of positive or negative signs.
Question 8 3.125 out of 3.125 points Correct The sample correlation coefficient is equal to the covariance of x and y divided by the square root of the product of sx2 times sy2.
Question 9 3.125 out of 3.125 points Correct A clinical trial was conducted comparing a new compound designed to improve wound healing in trauma patients to a placebo. After treatment for 5 days, 58% of the patients taking the new compound had a substantial reduction in the size of their wound as compared to 44% in the placebo group. The number of subjects would be required to detect the difference in proportions observed in the trial with 80% power at α = 0.05 in a two sided test is 200 in each group.
Question 10 3.125 out of 3.125 points Correct
A Kruskal-Wallis test is used to compare a continuous outcome in matched samples where there are greater than two matches.