Exam 3: Numerical Descriptive Measures

According to the Chebyshev rule, at least what percentage of the observations in any data set are contained within a distance of 2 standard deviations around the mean?

TABLE 3-10 The population of eight analysts at a software firm were asked to estimate the reuse rate when developing a new software system. The following data are given as a percentage of the total code written for a software system that is part of the reuse database. 50, 62.5, 37.5, 75.0, 45.0, 47.5, 15.0, 25.0 -Referring to Table 3-10, what is the mean percentage of the total code that is part of the reuse database?

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, construct a boxplot for the carbohydrate amounts.

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 coefficient of variation of the customs data is ________ percent.

In right-skewed distributions, the distance from Q₃ to the largest value is greater than the distance from the smallest observation to Q₁.

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 range of the rate of return?

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 five-number summary for the data in the customs sample consists of ________, ________, ________, ________, ________.

When extreme values are present in a set of data, which of the following descriptive summary measures are most appropriate?

TABLE 3-11 Given below are the closing prices for the Dow Jones Industrial Average (DJIA) and the Standard & Poor's (S&P) 500 Index over 10 weeks. Dow Jones 10,421 10,110 9,863 10,475 9,92 10,593 11,213 10,933 11,134 10,316 S\&P 500 1,379 1,356 1,343 1,410 1,389 1,463 1,529 1,499 1,516 1,355 -Referring to Table 3-11, for the week when the DJIA is high, you will expect the S&P index in that week to

The geometric mean is useful in measuring the rate of change of a variable over time.

In left-skewed distributions, which of the following is the 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, construct a boxplot of this sample.

The interquartile range is a measure of central tendency in a set of data.

TABLE 3-11 Given below are the closing prices for the Dow Jones Industrial Average (DJIA) and the Standard & Poor's (S&P) 500 Index over 10 weeks. Dow Jones 10,421 10,110 9,863 10,475 9,92 10,593 11,213 10,933 11,134 10,316 S\&P 500 1,379 1,356 1,343 1,410 1,389 1,463 1,529 1,499 1,516 1,355 -Referring to Table 3-11, how will you classify the linear relationship between the DJIA and the S&P 500 index?

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%. -You were told that the 1ˢᵗ, 2ⁿᵈ and 3ʳᵈ quartiles of female students' weight at a major university are 95 lbs, 125 lbs, and 138 lbs. What percentage of the students weigh less than 95 lbs?

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, what type of shape does the distribution of the sample appear to have?

Which of the following statements about the median is not true?

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 arithmetic mean age of the senior citizens to the nearest hundredth of a year.

The geometric mean is a measure of variation or dispersion in a set of data.

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 standard deviation of the ages of the senior citizens correct to the nearest hundredth of a year.