Question 1

Which of the following descriptive statistics is not measured in the same units as the data?

Accepted Answer

A) 35th percentile 
B) standard deviation 
C) variance 
D) interquartile range 
A) 35th percentile 
B) standard deviation 
C) variance 
D) interquartile range

Question 2

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 3

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 4

Which of the following is not a measure of dispersion?

Accepted Answer

A) the range 
B) the 50th percentile 
C) the standard deviation 
D) the interquartile range 
A) the range 
B) the 50th percentile 
C) the standard deviation 
D) the interquartile range

Question 5

The 50th percentile is the

Accepted Answer

A) mode 
B) median 
C) mean 
D) third quartile 
A) mode 
B) median 
C) mean 
D) third quartile

Question 6

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

Question 7

If two groups of numbers have the same mean, then their

Accepted Answer

A) standard deviations must also be equal 
B) medians must also be equal 
C) modes must also be equal 
D) None of the other answers are correct. 
A) standard deviations must also be equal 
B) medians must also be equal 
C) modes must also be equal 
D) None of the other answers are correct.

Question 8

The following frequency distribution shows the time (in minutes) that a sample of students uses the computer terminals per day.  
A)Compute the mean.
B)Compute the variance.
C)Compute the standard deviation.
D)Compute the coefficient of variation.

Accepted Answer

A.69.5
b.5

Question 9

Suppose annual salaries for sales associates from a particular store have a mean of $32,500 and a standard deviation of $2,500.
a.Calculate and interpret the z-score for a sales associate who makes $36,000.
b.Use Chebyshev's theorem to calculate the percentage of sales associates with salaries between $26,250 and $38,750.
c.Suppose that the distribution of annual salaries for sales associates at this store is bell-shaped. Use the empirical rule to calculate the percentage of sales associates with salaries between $27,500 and $37,500.
d.Use the empirical rule to determine the percentage of sales associates with salaries less than $27,500.
e.Still suppose that the distribution of annual salaries for sales associates at this store is bell-shaped. A sales associate makes $42,000. Should this salary be considered an outlier? Explain.

Accepted Answer

a.1.4. This sales associate's annual sal

Question 10

If a data set has an even number of observations, the median

Accepted Answer

A) can not be determined 
B) is the average value of the two middle items 
C) must be equal to the mean 
D) is the average value of the two middle items when all items are arranged in ascending order 
A) can not be determined 
B) is the average value of the two middle items 
C) must be equal to the mean 
D) is the average value of the two middle items when all items are arranged in ascending order

Which of the following descriptive statistics is not measured in the same units as the data?

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.

Which of the following is not a measure of dispersion?

The 50th percentile is the

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

If two groups of numbers have the same mean, then their

The following frequency distribution shows the time (in minutes) that a sample of students uses the computer terminals per day. A)Compute the mean. B)Compute the variance. C)Compute the standard deviation. D)Compute the coefficient of variation.

If a data set has an even number of observations, the median

Data and Statistics

Descriptive Statistics: Tabular and Graphical Presentations

Introduction to Probability

Discrete Probability Distributions

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Tests

Comparisons Involving Means, Experimental Design, and Analysis of Variance

Comparisons Involving Proportions and a Test of Independence

Simple Linear Regression

Multiple Regression

Statistical Methods for Quality Control

Time Series Analysis and Forecastng

Filters

Exam 3: Descriptive Statistics: Numerical Measures

Which of the following descriptive statistics is not measured in the same units as the data?

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.

Which of the following is not a measure of dispersion?

The 50th percentile is the

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

If two groups of numbers have the same mean, then their

The following frequency distribution shows the time (in minutes) that a sample of students uses the computer terminals per day. A)Compute the mean. B)Compute the variance. C)Compute the standard deviation. D)Compute the coefficient of variation.

If a data set has an even number of observations, the median

Data and Statistics

Descriptive Statistics: Tabular and Graphical Presentations

Introduction to Probability

Discrete Probability Distributions

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Tests

Comparisons Involving Means, Experimental Design, and Analysis of Variance

Comparisons Involving Proportions and a Test of Independence

Simple Linear Regression

Multiple Regression

Statistical Methods for Quality Control

Time Series Analysis and Forecastng

Filters

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