Exam 3: Numerical Descriptive Measures

The coefficient of variation is a measure of central tendency in the data.

TABLE 3-6 The rates of return of an Internet Service Provider over a 10 year period are: 10.25%, 12.64%, 8.37%, 9.29%, 6.23%, 42.53%, 29.23%, 15.25%, 21.52%, -2.35%. -Referring to Table 3-6, compute the geometric mean rate of return per year for the first three years.

TABLE 3-1 Health care issues are receiving much attention in both academic and political arenas. A sociologist recently conducted a survey of citizens over 60 years of age whose net worth is too high to qualify for Medicaid. The ages of 25 senior citizens were as follows: 60 61 62 63 64 65 66 68 68 69 70 73 73 74 75 76 76 81 81 82 86 87 89 90 92 -Referring to Table 3-1, determine the interquartile range of the ages of the senior citizens.

TABLE 3-3 The ordered array below represents the number of vitamin supplements sold by a health food store in a sample of 16 days. 19, 19, 20, 20, 22, 23, 25, 26, 27, 30, 33, 34, 35, 36, 38, 41 Note: For this sample, the sum of the values is 448, and the sum of the squared differences between each value and the mean is 812. -Referring to Table 3-3, the range of the number of vitamin supplements sold in this sample is ________.

In perfectly symmetrical distributions, which of the following is not a correct statement?

TABLE 3-4 The ordered array below represents the number of cargo manifests approved by customs inspectors of the Port of New York in a sample of 35 days: 16, 17, 18, 18, 19, 20, 20, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 24, 24, 24, 25, 25, 26, 26, 26, 27, 28, 28, 29, 29, 31, 31, 32, 32 Note: For this sample, the sum of the values is 838, and the sum of the squared differences between each value and the mean is 619.89. -Referring to Table 3-4, the standard deviation of the customs data is ________.

The line drawn within the box of the boxplot always represents the median.

TABLE 3-2 The data below represent the amount of grams of carbohydrates in a serving of breakfast cereal in a sample of 11 different servings. 11 15 23 29 19 22 21 20 15 25 17 -Referring to Table 3-2, the range in the carbohydrate amounts is ________ grams.

TABLE 3-4 The ordered array below represents the number of cargo manifests approved by customs inspectors of the Port of New York in a sample of 35 days: 16, 17, 18, 18, 19, 20, 20, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 24, 24, 24, 25, 25, 26, 26, 26, 27, 28, 28, 29, 29, 31, 31, 32, 32 Note: For this sample, the sum of the values is 838, and the sum of the squared differences between each value and the mean is 619.89. -Referring to Table 3-4, the arithmetic mean of the customs data is ________.

TABLE 3-5 The rates of return of a Fortune 500 company over the past 15 years are: 3.17%, 4.43%, 5.93%, 5.43%, 7.29%, 8.21%, 6.23%, 5.23%, 4.34%, 6.68%, 7.14%, -5.56%, -5.23%, -5.73%, -10.34% -Referring to Table 3-5, compute the geometric mean rate of return per year for the first four years.

TABLE 3-7 In a recent academic year, many public universities in the United States raised tuition and fees due to a decrease in state subsidies. The change in the cost of tuition, a shared dormitory room, and the most popular meal plan from the previous academic year for a sample of 10 public universities were as follows: $1,589, $593, $1,223, $869, $423, $1,720, $708, $1425, $922 and $308. -Referring to Table 3-7, what is the mean and median change in the cost?

TABLE 3-12 Given below are the rating and performance scores of 15 laptop computers. Performance Score 115 191 153 194 236 184 184 216 185 183 189 202 192 141 187 Overall Rating 74 78 79 80 84 76 77 92 83 78 77 78 78 73 77 -Referring to Table 3-12, what is the sample covariance between the performance scores and the rating?

Which descriptive summary measures are considered to be resistant statistics?

TABLE 3-5 The rates of return of a Fortune 500 company over the past 15 years are: 3.17%, 4.43%, 5.93%, 5.43%, 7.29%, 8.21%, 6.23%, 5.23%, 4.34%, 6.68%, 7.14%, -5.56%, -5.23%, -5.73%, -10.34% -Referring to Table 3-5, what is the shape of the distribution for the rate of return?

TABLE 3-8 The time period from 2006 to 2009 saw a great deal of volatility in the value of stocks. The data in the following table represent the total rate of return of our companies from 2006 to 2009. Year Company A Company B Company C Company D 2009 25.30 26.40 45.40 29.40 2008 -15.01 -22.10 -21.58 -20.90 2007 -5.44 -11.90 -1.03 -10.97 2006 -6.20 -9.10 -3.02 -10.89 -Referring to Table 3-8, calculate the geometric mean rate of return per year for Company D.

TABLE 3-2 The data below represent the amount of grams of carbohydrates in a serving of breakfast cereal in a sample of 11 different servings. 11 15 23 29 19 22 21 20 15 25 17 -Referring to Table 3-2, the third quartile of the carbohydrate amounts is ________ grams.

TABLE 3-12 Given below are the rating and performance scores of 15 laptop computers. Performance Score 115 191 153 194 236 184 184 216 185 183 189 202 192 141 187 Overall Rating 74 78 79 80 84 76 77 92 83 78 77 78 78 73 77 -Referring to Table 3-12, you will expect a decrease in the performance score of one laptop computer to be associated with

The coefficient of variation is a measure of relative variation.

TABLE 3-13 Energy drink consumption has continued to gain in popularity since the 1997 debut of Red Bull, the current leader in the energy drink market. Given below are the exam scores and the number of 12-ounce energy drinks consumed within a week prior to the exam of 10 college students. Exam Scores 75 92 84 64 64 86 81 61 73 93 Number of Drinks 5 3 2 4 2 7 3 0 1 0 -Referring to Table 3-13, what is the sample covariance between the exam scores and the number of energy drinks consumed?

TABLE 3-1 Health care issues are receiving much attention in both academic and political arenas. A sociologist recently conducted a survey of citizens over 60 years of age whose net worth is too high to qualify for Medicaid. The ages of 25 senior citizens were as follows: 60 61 62 63 64 65 66 68 68 69 70 73 73 74 75 76 76 81 81 82 86 87 89 90 92 -Referring to Table 3-1, calculate the coefficient of variation of the ages of the senior citizens.