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If you use t-test to compare 4 group means, Type 1 error rate decreases when you conduct multiple t-tests. 

Which of the following statistical tests would you use? You would like to see change in fasting LDL cholesterol levels in 200 men before and after they take a new kind of lipid lowering medication.

If we find that an ANOVA between 4 groups provides an F=7.2, P=0.075, how many post hoc tests do we need to perform?

If the population is skewed, the sampling distribution of all the sample means (x-bars) will be skewed. 

A two-sided test of H0: μ=0, α=0.05 (two sided), yields a p-value of 0.019.   Will the 95% confidence interval for μ include 0?

Which of the following statistical tests would you use? You would like to compare the blood pressure of 6-year old children in three groups healthy weight, overweight and obese (total n=300).

Survival analysis is used to determine the time to some event.

Cox Proportional Hazard Regression Models are like logistic regression combined with survival analysis and they often require large sample sizes when dealing with many variables.

In the following 2 by 2 contingency table of Survival at 5 years (yes or no) by Age at Diagnosis (=age 50), the data cell counts are presented as follows: under survival “yes” and age =50 cell count= 55, under survival “no” age =50 cell count=75.  What is the expected value for the cell under survival “yes” and age >=50 cell where the cell count= 55?

In our example 2 by 2 contingency table of Survival at 5 years (yes or no) by Age at Diagnosis (=age 50), the data cell counts are presented as follows: under survival “yes” and age =50 cell count= 55, under survival “no” age =50 cell count=75.  What is the overall calculated Chi-sq value?