Question 1

The interquartile range is the difference between the

Accepted Answer

A) first and second quartiles 
B) first and third quartiles 
C) second and third quartiles 
D) second and fourth quartiles 
A) first and second quartiles 
B) first and third quartiles 
C) second and third quartiles 
D) second and fourth quartiles

Question 2

The following data represent the daily demand (y in thousands of units) and the unit price (x in dollars) for a product.   
a.Compute and interpret the sample covariance for the above data.
b.Compute and interpret the sample correlation coefficient.

Accepted Answer

a.-160.14 (rounded). Since the

Question 3

Excel's __________ function can be used to compute the sample standard deviation.

Accepted Answer

A) MAX 
B) MODE 
C) VAR 
D) STDEV 
A) MAX 
B) MODE 
C) VAR 
D) STDEV

Question 4

A numerical measure of linear association between two variables is the

Accepted Answer

A) variance 
B) z-score 
C) correlation coefficient 
D) None of the other answers are correct. 
A) variance 
B) z-score 
C) correlation coefficient 
D) None of the other answers are correct.

Question 5

The starting salaries of a sample of community college graduates are given below.   
a.Compute the mean.
b.Compute the variance.
c.Compute the standard deviation.
d.Compute the coefficient of variation.

Accepted Answer

a.23.7
b.4

Question 6

For data skewed to the left, the skewness is

Accepted Answer

A) between 0 and .5 
B) less than 1 
C) positive 
D) negative 
A) between 0 and .5 
B) less than 1 
C) positive 
D) negative

Question 7

Chebyshev's theorem requires that z be

Accepted Answer

A) an integer 
B) greater than 1 
C) less than or equal to 3 
D) between 0 and 4 
A) an integer 
B) greater than 1 
C) less than or equal to 3 
D) between 0 and 4

Question 8

The number of hours worked per week for a sample of ten students is shown below.   
a.Determine the median and explain its meaning.
b.Compute the 70th percentile and explain its meaning.
c.What is the mode of the above data? What does it signify?

Accepted Answer

a.19; approximately 50% of the

Question 9

The measure of variability easiest to compute, but seldom used as the only measure, is the

Accepted Answer

A) range 
B) interquartile range 
C) standard deviation 
D) variance 
A) range 
B) interquartile range 
C) standard deviation 
D) variance

Question 10

The manager of Hudson Auto Repair has recorded the following frequency distribution for the cost of new parts used in doing an engine tune-up in a sample of 50 tune-ups.   Compute the sample mean, variance, and standard deviation.

Accepted Answer

Sample mean = 77.9;

Question 11

Exhibit 3-2
A researcher has collected the following sample data. The mean of the sample is 5.  
-A(n) __________ is an unusually small or unusually large data value.

Accepted Answer

A) sample statistic 
B) median 
C) z-score 
D) outlier 
A) sample statistic 
B) median 
C) z-score 
D) outlier

Question 12

Excel's __________ function can be used to compute the sample variance.

Accepted Answer

A) MAX 
B) MODE 
C) VAR 
D) STDEV 
A) MAX 
B) MODE 
C) VAR 
D) STDEV

Question 13

An important numerical measure of the shape of a distribution is the

Accepted Answer

A) correlation coefficient 
B) variance 
C) skewness 
D) relative location 
A) correlation coefficient 
B) variance 
C) skewness 
D) relative location

Question 14

$\mu$ is an example of a

Accepted Answer

A) population parameter 
B) sample statistic 
C) population variance 
D) mode 
A) population parameter 
B) sample statistic 
C) population variance 
D) mode

Question 15

The numerical value of the standard deviation can never be

Accepted Answer

A) larger than the variance 
B) zero 
C) negative 
D) all of these statements are correct 
A) larger than the variance 
B) zero 
C) negative 
D) all of these statements are correct

Question 16

The following observations are given for two variables.   
a.Compute and interpret the sample covariance for the above data.
b.Compute and interpret the sample correlation coefficient.

Accepted Answer

a.19.286 (rounded). Since the covariance

Question 17

The measure of location that is the most likely to be influenced by extreme values in the data set is the

Accepted Answer

A) range 
B) median 
C) mode 
D) mean 
A) range 
B) median 
C) mode 
D) mean

Question 18

The descriptive measure of dispersion that is based on the concept of a deviation about the mean is

Accepted Answer

A) the range 
B) the interquartile range 
C) both the range and the interquartile range 
D) the standard deviation 
A) the range 
B) the interquartile range 
C) both the range and the interquartile range 
D) the standard deviation

Question 19

In computing the pth percentile, if the index i is an integer the pth percentile is the

Accepted Answer

A) data value in position i 
B) data value in position i + 1 
C) average of data values in position i and i + 1 
D) average of data values in position i - 1 and i + 1 
A) data value in position i 
B) data value in position i + 1 
C) average of data values in position i and i + 1 
D) average of data values in position i - 1 and i + 1

Question 20

During a cold winter, the temperature stayed below zero for ten days (ranging from -20 to -5). The variance of the temperatures of the ten day period

Accepted Answer

A) is negative since all the numbers are negative 
B) must be at least zero 
C) cannot be computed since all the numbers are negative 
D) can be either negative or positive 
A) is negative since all the numbers are negative 
B) must be at least zero 
C) cannot be computed since all the numbers are negative 
D) can be either negative or positive

Exam 3: Descriptive Statistics: Numerical Measures

The interquartile range is the difference between the

The following data represent the daily demand (y in thousands of units) and the unit price (x in dollars) for a product. a.Compute and interpret the sample covariance for the above data. b.Compute and interpret the sample correlation coefficient.

Excel's __________ function can be used to compute the sample standard deviation.

A numerical measure of linear association between two variables is the

The starting salaries of a sample of community college graduates are given below. a.Compute the mean. b.Compute the variance. c.Compute the standard deviation. d.Compute the coefficient of variation.

For data skewed to the left, the skewness is

Chebyshev's theorem requires that z be

The number of hours worked per week for a sample of ten students is shown below. a.Determine the median and explain its meaning. b.Compute the 70th percentile and explain its meaning. c.What is the mode of the above data? What does it signify?

The measure of variability easiest to compute, but seldom used as the only measure, is the

The manager of Hudson Auto Repair has recorded the following frequency distribution for the cost of new parts used in doing an engine tune-up in a sample of 50 tune-ups. Compute the sample mean, variance, and standard deviation.

Exhibit 3-2 A researcher has collected the following sample data. The mean of the sample is 5. -A(n) __________ is an unusually small or unusually large data value.

Excel's __________ function can be used to compute the sample variance.

An important numerical measure of the shape of a distribution is the

μ\muμ is an example of a

The numerical value of the standard deviation can never be

The following observations are given for two variables. a.Compute and interpret the sample covariance for the above data. b.Compute and interpret the sample correlation coefficient.

The measure of location that is the most likely to be influenced by extreme values in the data set is the

The descriptive measure of dispersion that is based on the concept of a deviation about the mean is

In computing the pth percentile, if the index i is an integer the pth percentile is the

During a cold winter, the temperature stayed below zero for ten days (ranging from -20 to -5). The variance of the temperatures of the ten day period

Data and Statistics

Descriptive Statistics: Tabular and Graphical Displays

Introduction to Probability

Discrete Probability Distributions

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Tests

Inference About Means and Proportions With Two Populations

Inferences About Population Variances

Tests of Goodness of Fit, Independence and Multiple Proportions

Experimental Design and Analysis of Variance

Simple Linear Regression

Multiple Regression

Regression Analysis: Model Building

Time Series Analysis and Forecasting

Nonparametric Methods

Statistical Methods for Quality Control

Decision Analysis

Sample Survey

Filters

$\mu$ is an example of a

In computing the p^th percentile, if the index i is an integer the p^th percentile is the