Biostatistics Questions |

1. A one-tailed, one-mean Z test is conducted with the result that the null hypothesis is rejected. What would be the outcome of a two-tailed test with the same null hypothesis, sample mean, alpha and standard deviation of the population? (a) The null hypothesis will be rejected. (b) The null hypothesis will be accepted. (c) We will fail to reject the null hypothesis. (d)
2. As a increases (e.g., from .01 to .05), the power of a one mean Z test (a) remains unchanged (b) (c) decreases (d) may increase or decrease, but the direction is not knowable. 3. Confidence intervals of the form are designed to estimate the (a) sample mean. (b) sample standard deviation. (d) population standard deviation. 4. What is the upper limit of the two-sided 90% confidence interval for the following sample: X=14, 19, 15, 20, 26, 21? (a) 21.791 (b) 23.090 (c) 22.040 5. To carry out hypothesis tests or to compute confidence intervals for risk and odds ratios, we use the natural log of the sample risk or odds ratio in place of their actual values. We do this because: a. The sampling distributions of risk and odds ratios are approximately normally distributed.
c. It increases the power to find significant risk and odds ratios.
significance. 6. What consequences does adjustment for multiple comparisons using Bonferroniâ€™s procedure or a similar technique have? (a) It has almost no effect. (b) It increases the chance of making a Type I error. (c) It increases the power to find differences between pairs of group means.
(a) whether two continuous variables are correlated with each other. (c) the amount of variation in one variable explained by the other. (d) which categories of one variable are associated which categories of the other variable. |

Membership Management Software Powered by YourMembership.com® :: Legal