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Assessing Z-Scores and Outliers

See the attached file.

1. Thousands of students apply for admission to graduate schools in economics each year with the intention of obtaining a PhD. The mean and standard deviation of these 129 productivity scores were used to compute a z score for each economics program. Harvard University had the highest z score (z=5.08) and hence was the top ranked school; Howard University was ranked last with the lowest z score (z+-0.81).
a. Interpret the z score for Harvard
b. Interpret the z score for Howard
c. The authors of the southern economic journal article note that only 44 out of 129 schools have positive z scores indicating that the distribution of overall productivity is skewed to the right. Do you agree? (check your answer by constructing a histogram for the z scores in the file attached.)

2. A sample data set has a mean of 57 and a standard deviation of 11. Determine whether each of the following sample measurements are outliers
a. 65
b. 21
c. 72
d. 98.


Solution Preview

Thanks for letting me work on your post. Here is my explanation:

1. a) It means that the economics program at Harvard is ...

Solution Summary

The solution assesses the z-scores and outliers.