Exam 3: Numerical Descriptive Measures

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: -Referring to Table 3-1, calculate the variance of the ages of the senior citizens correct to the nearest hundredth of a year squared.

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 standard deviation of the change in the cost?

In a boxplot, the box portion represents the data between the first and third quartile values.

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.

TABLE 3-4 The ordered array below represents the number of cargo manifests approved by customs inspectors at 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 variance of the customs data is ________.

TABLE 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 Table 3-6, compute the arithmetic mean rate of return per year.

The median of the values 3.4, 4.7, 1.9, 7.6, and 6.5 is 1.9.

If the arithmetic mean of a numerical data set is greater than the median, the data are considered to be ________-skewed.

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 more than 125 lbs?

The smaller the spread of scores around the arithmetic mean,

The Z score of a value can never be negative.

TABLE 3-5 The rate 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 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.

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 median carbohydrate amount in the cereal is ________ grams.

TABLE 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 Table 3-6, construct a boxplot for the rate of return

TABLE 3-10 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. -Referring to Table 3-10, for the week when the DJIA is high, you will expect the S&P index in that week to

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 coefficient of variation of the number of vitamin supplements sold in this sample is ________ percent.

TABLE 3-10 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. -Referring to Table 3-10, what is the sample correlation coefficient between the DJIA and the S&P 500 Index?

Which descriptive summary measures are considered to be resistant statistics?

TABLE 3-9 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 3-9, what are the variance and standard deviation of the total code that is part of the reuse database?