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Statistics Test

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Submitted By Dmoney1976
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Name: ______________________

BUAD 820

MID-TERM

EXAM I

There are a total of 5 questions.
Question 1 is mandatory.
Answer any, but only 3 of the remaining 4 questions. Question 1 (has 5 parts)

1 Consider the data shown in the scatter plot below.

Which of the following statements is true about the correlation between X and Y.

a) X and Y are mildly, positively correlated

b) X and Y are perfectly, positively correlated

c) X and Y are mildly, negatively correlated

d) X and Y are perfectly, negatively correlated

e) X and Y are not correlated OR From the information given, we cannot tell whether X and Y are correlated

2 Five students from the 2000 MBA class took jobs in rocket science after graduation. Four of these students reported their starting salaries: $95,000, $106,000, $106,000, $118,000. The fifth student did not report a starting salary. Can we determine the median salary for all five students in this case (Yes/No)? Justify your answer. If you answer yes, indicate the median value.

3 Seven students from 1998 MBA class took jobs in dot-com companies after graduation. Five of the seven students reported starting salaries of $55,000, $90,250, $90,250, $95,500 and $105,000. Based on this information, is it possible to determine the largest possible value for the median salary for all seven students (Yes/No – justify your choice)? If you answer yes, indicate the largest possible median value.

4 One proposal that received little attention from Major League Baseball is to pay pitchers according to the following rule: each pitcher receives a base salary of $4.25 million, minus $0.25 million times his earned run average (ERA). A lower ERA is associated with better performance. If this rule were adopted, what would be the correlation between a pitcher’s earnings and ERA (indicate the

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