Exam 3: Numerical Descriptive Measures

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

SCENARIO 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 sometime in the past. -Referring to Scenario 3-11, how will you classify the linear relationship between the DJIA and the S&P 500 index?

The Z score of a value measures how many standard deviations the value is from the mean.

SCENARIO 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: 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 Scenario 3-4, the five-number summary for the data in the customs sample consists of ________, ________, ________, ________, ________.

SCENARIO 3-2 The data below represent the number of grams of carbohydrates in a serving of breakfast cereal in a sample of 11 different servings. -Referring to Scenario 3-2, the median carbohydrate amount in the cereal is ________ grams.

SCENARIO 3-3 The ordered array below represents the number of vitamin supplements sold by a health food store in a sample of 16 days. 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 Scenario 3-3, the standard deviation of the number of vitamin supplements sold in this sample is ________.

According to the empirical rule, if the data form a "bell-shaped" normal distribution, _______ percent of the observations will be contained within 1 standard deviation around the arithmetic mean.

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

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

According to the Chebyshev rule, at least 75% of all observations in any data set are contained within how many standard deviations around the mean?

SCENARIO 3-12 Given below are the rating and performance scores of 15 laptop computers. -Referring to Scenario 3-12, for a laptop computer that has a high rating, you will expect its performance score to

SCENARIO 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 Scenario 3-10, what are the variance and standard deviation of the total code that is part of the reuse database?

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

SCENARIO 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: -Referring to Scenario 3-1, identify which of the following is the correct statement.

The coefficient of variation is expressed as a percentage.

SCENARIO 3-3 The ordered array below represents the number of vitamin supplements sold by a health food store in a sample of 16 days. 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 Scenario 3-3, the third quartile of the number of vitamin supplements sold in this sample is ________.

In general, which of the following descriptive summary measures cannot be easily approximated from a boxplot?

SCENARIO 3-3 The ordered array below represents the number of vitamin supplements sold by a health food store in a sample of 16 days. 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 Scenario 3-3, the median number of vitamin supplements sold in this sample is ________.

According to the empirical rule, if the data form a "bell-shaped" normal distribution, _______ percent of the observations will be contained within 2 standard deviations around the arithmetic mean.

According to the empirical rule, if the data form a "bell-shaped" normal distribution, _______ percent of the observations will be contained within 3 standard deviations around the arithmetic mean.