Exam 3: Numerical Descriptive Measures

Instruction 3-3 The stem-and-leaf display below represents the number of vitamin supplements sold by a health food store in a sample of 16 days. Stem Leaves 1 99 2 0023 2 567 3 034 3 568 4 1 Note (1): 1H means the "high teens" = 15,16,17,18,or 19;2L means the "low twenties" = 20,21,22,23,or 24;2H means the "high twenties" = 25,26,27,28,or 29,etc. Note (2): For this sample,the sum of the observations is 448,the sum of the squares of the observations is 13,356,and the sum of the squared differences between each observation and the mean is 812. -Referring to Instruction 3-3,the range of the number of vitamin supplements sold in this sample is ________.

If a set of data is perfectly symmetrical,the arithmetic mean must be identical to the median.

Instruction 3-9 Given below are the rating and performance scores of 15 laptop computers. Performance 115 191 153 194 236 184 184 216 185 183 189 202 192 141 Overall 74 78 79 80 84 76 77 92 83 78 77 78 78 73 Rating -Referring to Instruction 3-9,what is the sample covariance between the performance scores and the rating?

Which of the following is NOT sensitive to extreme values?

Instruction 3-3 The stem-and-leaf display below represents the number of vitamin supplements sold by a health food store in a sample of 16 days. Stem Leaves 1 99 2 0023 2 567 3 034 3 568 4 1 Note (1): 1H means the "high teens" = 15,16,17,18,or 19;2L means the "low twenties" = 20,21,22,23,or 24;2H means the "high twenties" = 25,26,27,28,or 29,etc. Note (2): For this sample,the sum of the observations is 448,the sum of the squares of the observations is 13,356,and the sum of the squared differences between each observation and the mean is 812. -Referring to Instruction 3-3,the standard deviation of the number of vitamin supplements sold in this sample is ________.

The larger the Z score,the further is the distance from the observation to the median.

Instruction 3-2 The data below represents the amount of grams of carbohydrates in a serving of breakfast cereal in a sample of 11 different servings. $\text{11 15 23 29 19 22 21 20 15 25 17}$ -Referring to Instruction 3-2,the standard deviation of the carbohydrate amounts is ________ grams.

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 were 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

In a perfectly symmetrical bell-shaped "normal" distribution

Instruction 3-8 Given below is the frequency distribution of the number of defective tomatoes in 50 different shipments. Defective Items Frequency 0 but less than 5 35 5 but less than 10 7 10 but less than 15 5 15 but less than 20 2 20 but less than 25 1 25 but less than 30 0 -Referring to Instruction 3-8,what is the approximate variance?

Instruction 3-7 Given below is the frequency distribution of the 12-month rate of return achieved by 30 stocks. 12-month Rate of Return Number of Funds -0.10 but less than 0.0 3 0.0 but less than 0.1 5 0.1 but less than 0.2 6 0.2 but less than 0.3 10 0.3 but less than 0.4 6 -Referring to Instruction 3-7,what is the approximate variance?

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

Instruction 3-2 The data below represents the amount of grams of carbohydrates in a serving of breakfast cereal in a sample of 11 different servings. $\text{11 15 23 29 19 22 21 20 15 25 17}$ -Referring to Instruction 3-2,the median carbohydrate amount in the cereal is ________ grams.

Instruction 3-5 The rate of return of a listed Australian 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 Instruction 3-5,compute the geometric mean rate of return.

Instruction 3-4 The ordered array below represents the number of cargo manifests approved by customs inspectors at the Port of Brisbane 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 observations is 838,the sum of the squares of the observations is 20,684, and the sum of the squared differences between each observation and the mean is 619.89. -Referring to Instruction 3-4,the first quartile of the customs data is ________.

Instruction 3-4 The ordered array below represents the number of cargo manifests approved by customs inspectors at the Port of Brisbane 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 observations is 838,the sum of the squares of the observations is 20,684, and the sum of the squared differences between each observation and the mean is 619.89. -Referring to Instruction 3-4,the standard deviation of the customs data is ________.

Instruction 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 who have no private health insurance.The ages of 25 uninsured 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 Instruction 3-1,identify the median age of the uninsured senior citizens.

The 12-month rate of returns over a nine year period of a particular stock is 0.099,-0.289,0.089,0.226,0.041,0.161,0.064,-0.029 and 0.022.The geometric mean rate of return for this stock is ________.

As long as your analysis is objective,the interpretation of the data will also be objective.

Instruction 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 who have no private health insurance.The ages of 25 uninsured 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 Instruction 3-1,calculate the coefficient of variation of the ages of the uninsured senior citizens.