Question

6. The Computer Security Institute (CSI) conducts an annual survey of computer crime at U.S. businesses. CSI sends survey questionnaires to computer security personnel at all U.S. corporations and government agencies. The 2010 CSI survey was sent and 351 organizations responded. One of the survey questions asked respondents to indicate the percentage of monetary losses attributable to malicious actions by individuals within the organization (i.e., malicious insider actions). The following table summarizes the data for the 144 firms who experienced some monetary loss due to malicious insider actions Upper Bound 10 20 30 40 50 60 70 80 90 100 Lower Bound Midpoint Frequenc 43 10 20 30 40 50 60 70 80 90 15 25 35 45 16 65 75 85 95 4 144 a. Find the mean percentage loss for the sample of firms who reported some loss. b. Find the median, upper and lower quartiles. c. Draw the box plot. d. Would you describe this distribution as symmetric or skewed? Justify e. Compute the variance and the standard deviation of the monetary percentage losses.

Answer 1

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