Question 1

If the mean value of a distribution is 85 and the median is 67, the distribution must be skewed to the right.

Accepted Answer

A) True 
 B)False  True

Question 2

A random sample of 100 foxes was examined by a team of veterinarians to determine the prevalence of a particular type of parasite. Counting the number of parasites per fox, the veterinarians found that 69 foxes had no parasites, 17 had one parasite, and so on. A frequency tabulation of the data is given here:   What fraction of the parasite counts fall within two standard deviations of the mean?
______________
Within three standard deviations?
______________
Do these results agree with Tchebysheff's Theorem?
______________
With the Empirical Rule?
______________

Accepted Answer

0.95; 0.96; Yes; Yes

Question 3

The mode is the sum of a data set's minimum plus maximum values, divided by 2.

Accepted Answer

A) True 
 B)False  False

Question 4

According to Tchebysheff's Theorem, provided only   , regardless of the shape of a population's frequency distribution. The proportion of observations falling within k standard deviations of the mean is:

Accepted Answer

A)  at most 1 -   
B)  at least 1 -   
C)  at most 1 -   
D)  at least 1 -   
E)  exactly 1 -   
A)  at most 1 -   
B)  at least 1 -   
C)  at most 1 -   
D)  at least 1 -   
E)  exactly 1 -

Question 5

Mound-shaped data tend to cluster around a middle value.

Accepted Answer

A) True 
 B)False

Question 6

The median is one of the most commonly used measures of variability.

Accepted Answer

A) True 
 B)False

Question 7

The following five-number summary for a sample of size 500 were obtained: Minimum = 250,   and Maximum = 4,950. Based on this information, if you were to construct a box and whisker plot, the value 215 is considered an outlier.

Accepted Answer

A) True 
 B)False

Question 8

The average score for a class of 35 students was 70. The 20 male students in the class averaged 73. The 15 female students in the class averaged:

Accepted Answer

A)  73 
B)  70 
C)  66 
D)  60 
E)  35 
A)  73 
B)  70 
C)  66 
D)  60 
E)  35

Question 9

The difference between the largest and smallest values in an ordered array is called the interquartile range.

Accepted Answer

A) True 
 B)False

Question 10

For distributions of data that are skewed to the left or right, the median would likely be the best measure of center.

Accepted Answer

A) True 
 B)False

Question 11

The expression   is recognizable as the formula for:

Accepted Answer

A)  the sample variance, computed from ungrouped data 
B)  the population variance, computed from ungrouped data 
C)  the sample variance, computed from grouped data 
D)  the population variance, computed from grouped data 
E)  the population variance, computed from ungrouped or grouped data 
A)  the sample variance, computed from ungrouped data 
B)  the population variance, computed from ungrouped data 
C)  the sample variance, computed from grouped data 
D)  the population variance, computed from grouped data 
E)  the population variance, computed from ungrouped or grouped data

Question 12

Suppose the standard deviation for a given sample is known to be 12. If each data value in the sample is multiplied by 3, the standard deviation will be 36.

Accepted Answer

A) True 
 B)False

Question 13

A sample of n = 10 measurements consists of the following values:
15 12 13 16 11 12 14 15 11 13
a. Can you use Tchebysheff's Theorem to describe this data set?
______________
Why or why not?
____________________________
b. Can you use the Empirical Rule to describe this data set?
______________
Why or why not?
____________________________

Accepted Answer

Yes; The data is not

Question 14

Which of the following is the most frequently used measure of variation?

Accepted Answer

A)  the mean 
B)  the range 
C)  the variance 
D)  the standard deviation 
E)  the median 
A)  the mean 
B)  the range 
C)  the variance 
D)  the standard deviation 
E)  the median

Question 15

A sample of 20 observations has a standard deviation of 4. The sum of the squared deviations from the sample mean is 76.

Accepted Answer

A) True 
 B)False

Question 16

The value of the standard deviation will always exceed that of the variance.

Accepted Answer

A) True 
 B)False

Question 17

In all cases, the sum of the deviations of the measurements from their mean is 0.

Accepted Answer

A) True 
 B)False

Question 18

Which of the following statements is true?

Accepted Answer

A)  The population mean will always be larger than the mean of a sample selected from that population. 
B)  The population mean will always be larger than the population median. 
C)  The population mean and the mean of a sample selected from that population will usually be different values. 
D)  The population mean will always be equal to the population median. 
E)  All of these. 
A)  The population mean will always be larger than the mean of a sample selected from that population. 
B)  The population mean will always be larger than the population median. 
C)  The population mean and the mean of a sample selected from that population will usually be different values. 
D)  The population mean will always be equal to the population median. 
E)  All of these.

Question 19

An exam is given to both the fourth period class and the sixth period class. If a student's score is at the 30th percentile in the fourth period class but at the 60th percentile in the sixth period class, which one of the following statements is true?

Accepted Answer

A)  Students in the sixth period class generally performed better on the exam than the students in the fourth period class. 
B)  A person whose score is at the 15th percentile in the fourth period class will have a score at the 30th percentile in the sixth period class. 
C)  A person whose score is at the 70th percentile in the sixth period class will have a score at the 40th percentile in the fourth period class. 
D)  Students in the fourth period class generally performed better on the exam than students in the sixth period class. 
E)  None of these. 
A)  Students in the sixth period class generally performed better on the exam than the students in the fourth period class. 
B)  A person whose score is at the 15th percentile in the fourth period class will have a score at the 30th percentile in the sixth period class. 
C)  A person whose score is at the 70th percentile in the sixth period class will have a score at the 40th percentile in the fourth period class. 
D)  Students in the fourth period class generally performed better on the exam than students in the sixth period class. 
E)  None of these.

Question 20

Expressed in percentiles, the upper quartile is the 75th percentile.

Accepted Answer

A) True 
 B)False

If the mean value of a distribution is 85 and the median is 67, the distribution must be skewed to the right.

The mode is the sum of a data set's minimum plus maximum values, divided by 2.

According to Tchebysheff's Theorem, provided only , regardless of the shape of a population's frequency distribution. The proportion of observations falling within k standard deviations of the mean is:

Mound-shaped data tend to cluster around a middle value.

The median is one of the most commonly used measures of variability.

The following five-number summary for a sample of size 500 were obtained: Minimum = 250, and Maximum = 4,950. Based on this information, if you were to construct a box and whisker plot, the value 215 is considered an outlier.

The average score for a class of 35 students was 70. The 20 male students in the class averaged 73. The 15 female students in the class averaged:

The difference between the largest and smallest values in an ordered array is called the interquartile range.

For distributions of data that are skewed to the left or right, the median would likely be the best measure of center.

The expression is recognizable as the formula for:

Suppose the standard deviation for a given sample is known to be 12. If each data value in the sample is multiplied by 3, the standard deviation will be 36.

A sample of n = 10 measurements consists of the following values: 15 12 13 16 11 12 14 15 11 13 a. Can you use Tchebysheff's Theorem to describe this data set? Why or why not? b. Can you use the Empirical Rule to describe this data set? Why or why not? ________________

Which of the following is the most frequently used measure of variation?

A sample of 20 observations has a standard deviation of 4. The sum of the squared deviations from the sample mean is 76.

The value of the standard deviation will always exceed that of the variance.

In all cases, the sum of the deviations of the measurements from their mean is 0.

Which of the following statements is true?

An exam is given to both the fourth period class and the sixth period class. If a student's score is at the 30^th percentile in the fourth period class but at the 60^th percentile in the sixth period class, which one of the following statements is true?

Expressed in percentiles, the upper quartile is the 75^th percentile.

Describing Data With Graphs

Describing Bivariate Data

Probability and Probability Distributions

Several Useful Discrete Distributions

The Normal Probability Distribution

Sampling Distributions

Large-Sample Estimation

Large-Sample Tests of Hypotheses

Inference From Small Samples

The Analysis of Variance

Linear Regression and Correlation

Multiple Regression Analysis

Analysis of Categorical Data

Nonparametric Statistics

Filters

Exam 2: Describing Data With Numerical Measures

If the mean value of a distribution is 85 and the median is 67, the distribution must be skewed to the right.

The mode is the sum of a data set's minimum plus maximum values, divided by 2.

According to Tchebysheff's Theorem, provided only , regardless of the shape of a population's frequency distribution. The proportion of observations falling within k standard deviations of the mean is:

Mound-shaped data tend to cluster around a middle value.

The median is one of the most commonly used measures of variability.

The following five-number summary for a sample of size 500 were obtained: Minimum = 250, and Maximum = 4,950. Based on this information, if you were to construct a box and whisker plot, the value 215 is considered an outlier.

The average score for a class of 35 students was 70. The 20 male students in the class averaged 73. The 15 female students in the class averaged:

The difference between the largest and smallest values in an ordered array is called the interquartile range.

For distributions of data that are skewed to the left or right, the median would likely be the best measure of center.

The expression is recognizable as the formula for:

Suppose the standard deviation for a given sample is known to be 12. If each data value in the sample is multiplied by 3, the standard deviation will be 36.

Which of the following is the most frequently used measure of variation?

A sample of 20 observations has a standard deviation of 4. The sum of the squared deviations from the sample mean is 76.

The value of the standard deviation will always exceed that of the variance.

In all cases, the sum of the deviations of the measurements from their mean is 0.

Which of the following statements is true?

An exam is given to both the fourth period class and the sixth period class. If a student's score is at the 30th percentile in the fourth period class but at the 60th percentile in the sixth period class, which one of the following statements is true?

Expressed in percentiles, the upper quartile is the 75th percentile.

Describing Data With Graphs

Describing Bivariate Data

Probability and Probability Distributions

Several Useful Discrete Distributions

The Normal Probability Distribution

Sampling Distributions

Large-Sample Estimation

Large-Sample Tests of Hypotheses

Inference From Small Samples

The Analysis of Variance

Linear Regression and Correlation

Multiple Regression Analysis

Analysis of Categorical Data

Nonparametric Statistics

Filters

An exam is given to both the fourth period class and the sixth period class. If a student's score is at the 30^th percentile in the fourth period class but at the 60^th percentile in the sixth period class, which one of the following statements is true?

Expressed in percentiles, the upper quartile is the 75^th percentile.