Exam 3: Numerical Descriptive Measures

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

When extreme values are present in a set of data,which of the following descriptive summary measures are most appropriate?

The coefficient of variation measures variability in a data set relative to the size of the arithmetic mean.

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 coefficient of variation of the carbohydrate amounts is ________ percent.

The ________ measures the total spread of the data.

Instruction 3-3B 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 1H 99 2L 0023 2H 567 3L 034 3H 568 4L 1 -Referring to Instruction 3-3B,what type of shape does the distribution of the sample appear to have?

In a set of numerical data,the value for Q3 can never be smaller than the value for Q1.

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

The rate of return for the S&P 500 over a seven year period is -0.029,-0.061,-0.493,-0.286,-0.160,-0.186 and -0.224.The geometric mean rate of return is ________.

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 correlation coefficient between the performance scores and the rating?

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 first quartile of the carbohydrate amounts is ________ grams.

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

The Z scores can be used to identify outliers.

If the mean is less than the median,the distribution is likely to be positive or right-skewed.

If the values are all the same (so that there is no variation in the data),the range,interquartile range,variance and standard deviation will all equal zero.

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,for a laptop computer that has a high rating,you will expect its performance score to ________.

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

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

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 variance of the ages of the uninsured senior citizens correct to the nearest hundredth of a year squared.

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