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What is the range of the covariance between 2 variables?

Describe what the central limit theorem is and why it is important in statistical hypothesis testing.

Extra Credit – No Penalty for Trying Suppose a researcher compares 4 groups (Freshmen, Sophomores, Juniors, Seniors) on the average number of steps taken per day, and finds an overall significant F-ratio. What is the logic of using post hoc methods like the Tukey method or Bonferroni method in making pairwise comparisons (why are these special methods needed)?

Extra Credit – No Penalty for Trying What numerical values for skewness and kurtosis would indicate a normal distribution for a set of scores?

A researcher was interested in comparing 3 group conditions: Meditation, Progressive Relaxation, and a Control condition on heart rate. 28 freshmen undergraduates from USF were randomly selected.  From these 28 students, 13 were randomized to the Control Condition, 8 were randomly assigned to Meditation, and 7 were randomly assigned to Progressive Relaxation. What statistical technique would be used in this study?

For an independent samples t-test, list the 3 assumptions underlying the statistical test.

In an exercise group, a person’s z-score for BMI was z=0. Is this person’s BMI score an outlier?

A researcher was interested in evaluating an intervention that would impact body mass. The researcher was also interested in evaluating if there were sex differences in body mass. The researcher recruited 10 males and 10 females for the study. For the 10 males, 5 males were randomly assigned to the intervention and 5 males were randomly assigned to a control condition. Similarly, for the 10 females, 5 females were randomly assigned to the intervention and 5 females were randomly assigned to a control condition. How many degrees of freedom would there be for Sex?

What effect will increasing the sample size have on the width of the confidence band around the estimated parameter?

Extra Credit – No Penalty for Trying If a researcher has a nominal/categorical variable like Sport Participated In (Swimming, Basketball, Track, Soccer), what is meant when a researcher creates “dummy variables” to represent this variable?  What is a dummy variable?