Exam 3: Numerical Descriptive Measures

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,compute the geometric mean rate of return per year for the first four years.

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 range of the number of vitamin supplements sold in this sample is ________.

In a set of numerical data,the value for Q₂ is always halfway between Q₁ and Q₃.

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

A manufacturer of flashlight batteries took a sample of 130 batteries from a day's production and used them continuously until they were drained.The number of hours until failure are recorded.Given below is the boxplot of the number of hours it took to drain each of the 130 batteries.The distribution of the number of hours is

If the distribution of a data set were perfectly symmetrical,the distance from Q₁ to the median would always equal the distance from Q₃ to the median in a boxplot.

Which of the following is not sensitive to 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%. -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 between 95 and 138 lbs?

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

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

In a perfectly symmetrical distribution

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,what is the shape of the distribution for the rate of return?

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,are the data skewed? If so,how?

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 3-6 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%. -The rate of return for the S&P 500 over a four year period is -0.029,-0.061,-0.493,and -0.286.The geometric mean rate of return per year is ________.

In a sample of size 40,the sample mean is 15.In this case,the sum of all observations in the sample is Xᵢ = 600.

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

Which of the following is sensitive to 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%. -The larger the Z score,the farther is the distance from the value to the median.

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%. -The Z score of a value can never be negative.