Exam 3: Numerical Descriptive Measures

3-22 Numerical Descriptive Measures 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 Scenario 3-4, the third quartile of the customs data is .

SCENARIO 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 Scenario 3-7, what is the five-number summary of the change in the cost?

According to the Chebyshev rule, at least 93.75% of all observations in any data set are contained within how many standard deviations around the mean?

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: 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 Scenario 3-1, does the distribution of the sample appear to be leptokurtic or platykurtic?

The five-number summary consists of the smallest value, the first quartile, the median, the third quartile, and the largest value.

Which of the following is NOT a measure of central tendency?

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. $19,19,20,20,22,23,25,26,27,30,33,34,35,36,38,41$ 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 Scenario 3-3, the five-number summary of the data in this 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. $11,15,23,29,19,22,21,20,15,25,17$ -Referring to Scenario 3-2, the arithmetic mean carbohydrates in this sample is grams.

Which of the following statistics is not a measure of central tendency?

SCENARIO 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 Scenario 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 rule, a value is considered an extreme value if its Z score is greater than 3.

A positive kurtosis measure means a sample distribution is peaked than adistribution.

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. $19,19,20,20,22,23,25,26,27,30,33,34,35,36,38,41$ 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 Scenario 3-3, is the number of vitamin supplements sold in this sample right- or left- skewed?

The Z score of a value can never be negative.

SCENARIO 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 Scenario 3-7, what is the interquartile range of the change in the cost?

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?

SCENARIO 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 Scenario 3-7, is the change in the cost leptokurtic or platykurtic?

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

SCENARIO 3-6 The rate 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 Scenario 3-6, compute the arithmetic mean rate of return per year.

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.