Statistics for Business Decision-Making Spring 2015 Assignment (1)

Instructions:

The assignment is due Monday February 9, 2015 in or before the class. The solutions must be typed and relevant Excel output should be embedded in the solutions.

Handwritten solutions will not be graded. Late submissions will not be accepted. You can work in groups of at most five and submit one solution.

1. The following information regarding the ten richest Americans was reported in a recent issue of Forbes.

Name Ranking Worth ($Billions) Age Marital Status Source Gates, William 1 59.0 51 married Microsoft Buffett, Warren 2 52.0 77 married Berkshire Hathaway Adelson, Sheldon 3 28.0 74 married casinos, hotels Ellison, L. J. 4 26.0 63 married Oracle Brin, Sergey 5 18.5 34 married Google Page, Larry 5 18.5 34 single Google Kerkorian, Kirk 7 18.0 90 divorced investments, casinos Dell, Michael 8 17.2 42 married Dell Koch, Charles 9 17.0 71 married oil, commodities Koch, David 9 17.0 67 married oil, commodities

(a) How many elements are in the above data set?

(b) How many variables are in this data set?

(c) How many observations are in this data set?

(d) Which variables are qualitative and which are quantitative?

(e) What measurement scale is used for each variable?

2. Problem 2.8 page 40.

3. Problem 2.75 page 76.

4. A bank wishes to study the amount of time it takes to complete a withdrawal transaction from one of its ATMs (automated teller machines). On a particular day, 63 withdrawal transactions are observed between 10 A.M. and noon. The time required to complete each transaction is given Data ATMTime.

(a) Find the mean, the median, the range, variance, and standard deviation of the transaction times. How would you describe the distribution of the transaction times? Explain.

(b) Find the five-number summary of the transaction times.

(c) Display the transaction times using a boxplot. Describe the distribution of the transaction times.

(d) Eliminate the largest two values of the transaction times and repeat part (c). Comment on the results.