Deck 3: Data Description

Question 1

The unbiased estimator is included in the formula for calculating the variance of a sample because
without it, the computed variance usually underestimates the population variance.

Answer 1

True

Question 2

For a set of data with mean 12 and variance 36, approximately 68% of the values will fall between 0 and

Answer 2

False

Question 3

To find the mean for grouped data, we take the sum of all the frequencies, multiply this by the midpoint
of each class and then divide boor the sample size.

Answer 3

False

Question 4

A weighted mean is used when the values of the data set are not all equally represented.

Question 5

The procedure for finding the mean for grouped data assumes that the mean of all the raw data values in
each class is equal to the midpoint of the class.

Question 6

Methods commonly called traditional statistics include using measures of position, Chebyshev's theorem,
and the coefficient of variation.

Question 7

For the sample 1, 8, 7, 2, 9, 15, and 18, the mean is 7.6.

Question 8

The range of a data set is the distance between the highest value and the lowest value.

Question 9

If the range is divided by 6, an approximate value for the standard deviation is obtained.

Question 10

Question 11

The percentile corresponding to a given value X is computed by adding the 0.5 to number of values below
X and dividing this value by the total number of values within the data set.

Question 12

The coefficient of variation is the mean divided by the standard deviation expressed as a percentage.

Question 13

A five-number summary of a data set consists of the minimum, maximum.

Question 14

The range rule of thumb is only an approximation and should only be used when the distribution of data
values is unimodal and roughly symmetric.

Question 15

The variance is the square root of the standard deviation of a set of data.

Question 16

The interquartile range or IQR is found by subtracting the mean from the maximum value of a data
set.

Question 17

Chebyshev's theorem can be used to find the minimum percentage of data values that will fall between
any two given values.

Question 18

The median can be a more appropriate measure of central tendency if the distribution of the data is
extremely skewed.

Question 19

The following data set could also be referred to as a data array:
3, 4, 2, 7.

Question 20

John, who was a business student, received a grade corresponding to a z-score of 1 whereas his girl friend
who was studying engineering, received a grade corresponding to a z-score of 2. John's grade score was
necessarily below his girl friend's grade

Question 21

A student received the following grades: An A in Statistics (4 credits), a C in Physics II (5 credits), a B in Sociology (3 credits), a B in a Literature seminar (2 credits), and a D in Tennis (1 credit). Assuming
A = 4 grade points, B = 3 grade points, C = 2 grade points, D = 1 grade point, and F = 0 grade points, the
Student's grade point average is:

A) 2.80
B) 3.13
C) 2.90
D) 2.92

Question 22

Given the following data set, the IQR is 3.

Question 23

Given the following data set, the IQR is 7.

Question 24

What is the mode of the following numbers? -10, 4, 2, -2, 2, 0, -3

A) -4
B) 0
C) -2
D) 2

Question 25

Which of the following is the mode for the given data? 5, 4, 3, 4, 5, 6, 5, 5, 3, 4

A) 3
B) 4
C) 5
D) 6

Question 26

What is the median of the following numbers? -12, 2, 0, -4, 0, -5, -4, 0

A) -6
B) -2
C) -4
D) 0

Question 27

What is the mean of the following numbers? -12, -9, -5, -4, 0

A) -9
B) -6
C) -5
D) -2

Question 28

Find the median for the following data. 6, 7, 4, 5, 3, 7, 4

A) 3
B) 4
C) 5
D) 7

Question 29

What is the median of the following numbers? -12, -9, -5, -4, 0

A) -6
B) -5
C) -4
D) -2

Question 30

What is the midrange of the following numbers? 5, 11, 10, 12, 4, 12, 18, 18, 18

A) 11
B) 12
C) 5
D) 18

Question 31

A) The mean is the same as the median, but the mode can be different.
B) The mean, the median, and the mode are the same.
C) The median and the mode are the same, but the mean can be different.
D) The mean, the median, and the mode are different.

Question 32

What is the mean of the following numbers? 4, 6, 9, 11, 15

A) 6
B) 8
C) 9
D) 10

Question 33

What is the range of the numbers -3, 2, -5, 3, 11:

A) -3
B) 2
C) 6
D) 16

Question 34

What is the median of the following numbers? 1, 3, 6, 8, 12

A) 3
B) 5
C) 6
D) 7

Question 35

Which of the following is the correct mean for the given data? 7, 8, 13, 9, 10, 11

A) 10
B) 9.7
C) 9.67
D) 9

Question 36

The range of the set of numbers {4, 13, 3, 10, 5} is

A) 3
B) 13
C) 8
D) 10

Question 37

Find the mode for the number of police officers in selected city districts. 24, 26, 24, 30, 23, 28, 19, 31, 24, 26, 19

A) 23
B) 24
C) 26
D) 28

Question 38

Determine the range for this data: 6, 14, 10, 8, 21:

A) 6
B) 10
C) 15
D) 21

Question 39

Determine the range for this data: 4, 7, 3, 16, 5, 22, and 8:

A) 4
B) 3
C) 14
D) 19

Question 40

What is the term for a characteristic or measure obtained by using all the data values for a specific population?

A) variable
B) mode
C) statistic
D) parameter

Question 41

If a set of data has 64 points and variance 16, then the standard deviation is

A) 2.00
B) 0.06
C) 0.50
D) 4.00

Question 42

A student scored 75 points on a test where the mean score was 81 and the standard deviation was 6. The student's z-score was

A) 13.50
B) 0.17
C) -0.17
D) -1.00

Question 43

If the mean of a set of data is 26.00, and 33.50 has a z-score of 0.75, then the standard deviation must be:

A) 10.00
B) 100.00
C) 5.00
D) 50.00

Question 44

What is the correct standard score for a batter who normally averages 0.325, with a standard deviation of 0.065 if he scores 0.410 for one game?

A) 1.308
B) 0.410
C) 0.325
D) 1.275

Question 45

If the mean of a set of data is 19.00, and 7.00 has a z-score of -1.50, then the standard deviation must be:

A) 8.00
B) 64.00
C) 4.00
D) 32.00

Question 46

All the values in a dataset are between 9 and 12, except for one value of 92. That value 92 is likely to be

A) the range
B) an outlier
C) the mean
D) the boxplot

Question 47

A student scored 89 points on a test where the mean score was 83 and the standard deviation was 3. The student's z-score was

A) 27.67
B) 29.67
C) 0.67
D) 2.00

Question 48

Which of the following is true?

A) $D _ { 5 } = P _ { \mathrm { S } } = Q _ { 5 }$
B) $D _ { 50 } = P _ { 5 } = Q _ { 25 }$
C) $D _ { 5 } = P _ { 50 } = Q _ { 2 }$
D) $D _ { 50 } = P _ { 5 } = Q _ { 2 }$

Question 49

According to Chebyshev's theorem, the proportion of values from a data set that is further than 2 standard deviations from the mean is no more than:

A) 0.50
B) 0.13
C) 1.00
D) 0.25

Question 50

Question 51

Given that the mean of a set of data is 25 and the standard deviation is 3, what would be the coefficient of variation?

A) 0.12
B)
C) 8.33
D)

Question 52

A) The art major has a higher score than the theatre major.
B) The theatre major has a higher score than the art major.
C) Both students have the same score.
D) Neither student received a positive score; therefore, the higher score cannot be determined.

Question 53

The maximum of the set of numbers {6, 16, -5, 11, 5} is

A) -5
B) 16
C) 9.5
D) 13

Question 54

Question 55

The minimum of the set of numbers {-6, 15, -5, 11, 5} is

A) -6
B) 15
C) 9
D) 21

Question 56

Given that the variance for a data set is 1.20, what would be the standard deviation?

A) 1.10
B) 1.44
C) 1.20
D) 0.60

Question 57

If a set of 9 numbers has standard deviation 8, then its variance is

A) 64.00
B) 2.67
C) 21.33
D) 24.00

Question 58

The grades for a trigonometry exam follow. Find the range. 85, 76, 93, 82, 84, 90, 75

A) 76
B) 9
C) 11
D) 18

Question 59

If the value 5 has z-score of -0.75 in a dataset, then the mean of that dataset is

A) 5
B) 4.25
C) 5.75
D) It cannot be determined from the data given

Question 60

A distribution in which approximately of the data values fall within one standard deviation of the mean behaves according to

A) the empirical rule.
B) a symmetrical distribution.
C) a boxplot.
D) differential statistics.

Question 61

If the boxplot for one set of data is much wider than the boxplot for a second set of data, then

A) the mean of the first set of data must be larger than the mean of the second set of data
B) the median of the first set of data must be larger than the median of the second set of data
C) the second set of data must contain several outliers
D) none of the above need to be true

Question 62

A) Option A
B) Option B
C) Option C
D) Option D
E) Option E

Question 63

If the five number summary for a set of data is 2, 5, 8, 9, and 18, then the mean of this set of data is

A) 10
B) 8
C) 7
D) there is insufficient information to calculate the mean

Question 64

A) 141.4
B) 145.6
C) 133.4
D) 136.0

Question 65

A) 180.4
B) 197.3
C) 192.6
D) 183.2

Question 66

The ________________ is the mode for grouped data.
________________________________________

Question 67

The maximum value in a data set is 100 and the minimum value is 20, an approximate value for the standard deviation is

A) 20
B) 13.3
C) 30
D) It cannot be determined from the data given

Question 68

A) 28.8
B) 12.6
C) 26.3
D) 31.3

Question 69

A) 76.6
B) 72.6
C) 81.6
D) 83.6

Question 70

In a class of 200 students, Bill's mark corresponded to a z-score of 1 and Tom's mark corresponded to a z-score of 2. If the distribution of marks was bell-shaped ('normal') than the number of students with a
Grade between Bill's mark and Tom's mark is closest to

A) 5
B) 10
C) 20
D) 30

Question 71

A) 37.2
B) 40.5
C) 36.4
D) 38.7

Question 72

For the data set 10, -3, 4 8, the range rule of thumb is

A) 1.8
B) 1.5
C) 3.3
D) 2.2

Question 73

_______________ applies to any distribution regardless of its shape.
________________________________________

Question 74

The _______________ and ______________ are used to determine the consistency of a variable.
________________________________________

Question 75

A) 38.1
B) 39.6
C) 41.1
D) 40.8

Question 76

A) 30.2
B) 29.8
C) 30.3
D) 29.5

Question 77

A) 43.5
B) 40.2
C) 48.6
D) 42.3

Question 78

The ______________ is the average of the squares of the distance each value is from the mean.
________________________________________

Question 79

A ______________ is the midpoint in a data array.
________________________________________

Question 80

A) 78.6
B) 76.8
C) 70.4
D) 74.0