Exam 3: Numerical Descriptive Measures

Which measure of central tendency can be used for both numerical and categorical variables?

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, you will expect a decrease in the amount of energy drink consumed within the week prior to the exam to be associated with

As a general rule, a value is considered an extreme value if its Z score is greater than -3.

In exploratory data analysis, a boxplot can be used to illustrate the median, quartiles, and extreme values.

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 arithmetic mean rate of return per year.

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, you will expect an increase in the DJIA to be associated with

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 interquartile range in the carbohydrate amounts is ________ grams.

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 first quartile of the ages of the senior citizens.

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 median of the customs data is ________.

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 A.

Which of the following is sensitive to extreme values?

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 which of the following is the correct statement.

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, what is the sample covariance between the DJIA and the S&P 500 index?

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 C.

According to the Chebyshev rule, at least what percentage of the observations in any data set are contained within a distance of 3 standard deviations around the mean?

The coefficient of variation is expressed as a percentage.

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

Data on the change in the cost of tuition, a shared dormitory room, and the most popular meal plan from one academic year to the next academic year for a sample of 100 public universities are collected. Below is the boxplot for the change in cost in dollars. The distribution of the change in cost is

In right-skewed distributions, which of the following is the correct statement?

The median of a data set with 20 items would be the average of the 10th and the 11th items in the ordered array.