Deck 4: Describing Data: Displaying and Exploring Data

Question 1

A scatter diagram is used to illustrate a relationship between gender and the preference for Coke or Pepsi.

Answer 1

False

Question 2

The coefficient of skewness is the standard deviation divided by the mean.

Answer 2

False

Question 3

A scatter diagram of sales versus production is labeled with sales on the Y-axis and production on the X-axis.

Answer 3

True

Question 4

Percentiles divide a distribution into 100 equal parts.

Question 5

The 50^th percentile of a distribution is the same as the distribution mean.

Question 6

A dot plot is useful for showing the range of the data.

Question 7

Quartiles divide a distribution into 10 equal parts.

Question 8

A relationship between two nominal variables is summarized by a contingency table.

Question 9

Quartiles divide a distribution into four equal parts.

Question 10

Pearson's coefficient of skewness is a measure of a distribution's symmetry.

Question 11

A box plot graphically shows the 10^th and 90^th percentiles.

Question 12

A dot plot is useful for quickly graphing frequencies in a small data set.

Question 13

The "box" in a box plot shows the interquartile range.

Question 14

A dot plot is useful for showing individual observations.

Question 15

A box plot shows the skewness of a distribution.

Question 16

A dot plot is an easy way to represent the relationship between two variables.

Question 17

A student scored in the 85^th percentile on a standardized test. This means that the student scored lower than 85% of all students who took the test.

Question 18

If a distribution is negatively skewed, the distribution is not symmetrical and the long tail is to the left.

Question 19

A scatter diagram of sales versus production may be constructed by plotting the minimum, first quartile, median, third quartile, and maximum values of each variable.

Question 20

A dot plot shows the symmetry of a distribution.

Question 21

In a distribution, the second quartile corresponds with the __________.

A) Mean
B) Median
C) Mode
D) Variance

Question 22

To locate the percentile for a given observation in a data set, the data must be ___________.

A) Sorted and listed from the minimum to the maximum values
B) Displayed in a histogram
C) Summarized in a frequency distribution
D) Distributed symmetrically around the mean

Question 23

A stem-and-leaf diagram shows the actual data values.

Question 24

What does the interquartile range describe?

A) The range of the lower 50% of the observations
B) The range of the middle 50% of the observations
C) The range of the upper 50% of the observations
D) The ranges of the lower 25% and the upper 25% of the observations

Question 25

The interquartile range is graphically presented in a ___________.

A) Dot plot
B) Stem-and-leaf display
C) Box plot
D) Contingency table

Question 26

A dot plot shows ____________.

A) The general shape of a distribution
B) The mean, median, and mode
C) The relationship between two variables
D) The interquartile range

Question 27

A dot plot is best applied for a data set with __________.

A) 1,000 observations
B) 50 observations
C) More than one variable
D) One mode

Question 28

A box plot shows ___________.

A) The mean and variance
B) The relative symmetry of a distribution for a set of data
C) The 10^th and 90^th percentiles of a distribution
D) The deciles of a distribution

Question 29

The following graph is a ____________.

A) Dot plot
B) Stem-and-leaf diagram
C) Box plot
D) Contingency table

Question 30

In the following set of data: what are the first, second, and third quartiles?

A) 1, 6, and 100
B) 3, 5, and 9
C) 3, 6, and 9
D) 1, 5, and 100

Question 31

In a stem-and-leaf display, the leaf represents a class of a frequency distribution.

Question 32

The following graph is a:

A) Dot plot
B) Stem-and-leaf display
C) Box plot
D) Contingency table

Question 33

A dot plot is best applied when _____________________.

A) The mean, median, and mode are equal
B) The general shape of a distribution is symmetric
C) The relationship between two variables is summarized
D) A single variable is summarized

Question 34

The test scores for a class of 147 students are computed. What is the location of the test score associated with the third quartile?

A) 111
B) 37
C) 74
D) 75%

Question 35

What statistics are needed to draw a box plot?

A) The minimum, maximum, median, first and third quartiles.
B) The median, mean, and standard deviation.
C) The median and interquartile range.
D) The mean and standard deviation.

Question 36

Quartiles divide a distribution into ___________.

A) 2 equal parts
B) 4 equal parts
C) 10 equal parts
D) 100 equal parts

Question 37

A dot plot can be used to show _________________.

A) The mean, median, and mode
B) The general shape of a distribution for a nominal qualitative variable
C) The distribution for a quantitative variable
D) The interquartile range

Question 38

If a student places in the 99^th percentile on an exam, she performed better than 99% of all students who completed the exam. Her performance is similar to a statement based on a __________.

A) Frequency table
B) Cumulative frequency distribution
C) Histogram
D) Pie chart

Question 39

In a stem-and-leaf display, the leaf represents the members of a class in a frequency distribution.

Question 40

Percentiles divide a distribution into _____________.

A) 2 equal parts
B) 4 equal parts
C) 10 equal parts
D) 100 equal parts

Question 41

The following table is a:

A) Dot plot
B) Stem-and-leaf display
C) Box plot
D) Contingency table

Question 42

A stem-and-leaf display includes the following row: 5 | 10 11 31 52 79 98. Assume that the data is rounded to the nearest whole number.

A) The frequency of the class is seven.
B) The minimum value in the class is 5.
C) The maximum value in the class is 98.
D) The class interval is 100.

Question 43

What is the possible range of values for Pearson's coefficient of skewness?

A) -1 and +1
B) -3 and +3
C) 0% and 100%
D) Unlimited values

Question 44

The following graph is a ___________.

A) Dot plot
B) Stem-and-leaf display
C) Box plot
D) Scatter plot

Question 45

Outliers are clearly presented in a _____________.

A) Dot plot
B) Stem-and-leaf display
C) Box plot
D) Contingency table

Question 46

In the following table,

A) There are 16 observations.
B) There are four observations in the second class.
C) There are ten observations less than thirty.
D) There are ten observations greater than thirty.

Question 47

What is the value of the Pearson coefficient of skewness for a distribution with a mean of 17, a median of 12, and a standard deviation of 6?

A) +2.5
B) -2.5
C) +0.83
D) -0.83

Question 48

The following graph is _______________.

A) Positively skewed
B) Negatively skewed
C) Symmetric
D) Uniformly distributed

Question 49

If the coefficient of skewness is equal to zero, the shape of the distribution is __________.

A) Negatively skewed
B) Symmetric
C) Positively skewed
D) Unknown

Question 50

The following graph illustrates _______________.

A) A positive or direct relationship
B) A negative or inverse relationship
C) No relationship
D) A distribution for a single variable

Question 51

Using the following statistics to describe a distribution of data, what is the interquartile range? Minimum = 10
Q1 = 25
Median = 50
Q3 = 75
Maximum = 95

A) 85
B) 50
C) 15
D) 20

Question 52

A sample of experienced typists revealed that their mean typing speed is 87 words per minute and the median typing speed is 73 words per minute. The standard deviation of typing speed is 16.9 words per minute. What is the Pearson coefficient of skewness?

A) -2.5
B) -4.2
C) +4.2
D) +2.5

Question 53

The median of a sample will always equal the:

A) mode.
B) mean.
C) 50^th percentile.
D) All of these are correct.

Question 54

A contingency table would be used to summarize data such as ________.

A) Company employees by gender and organizational title
B) Company employees by gender and age
C) Company employees by compensation and age
D) Company employees by compensation and years with the company

Question 55

In the following table,

A) The median is 2.5.
B) The minimum value is 135.
C) The maximum value is 456.
D) The range is 33.

Question 56

In a contingency table, we describe the relationship between ________.

A) Two variables measured at the ordinal or nominal level
B) Two variables, one measured as an ordinal variable and the other as a ratio variable
C) Two variables measured at the interval or ratio level
D) A variable measure on the interval or ratio level and time

Question 57

In a scatter diagram, we describe the relationship between __________.

A) Two variables measured at the ordinal level
B) Two variables, one measured as an ordinal variable and the other as a ratio variable
C) Two variables measured at the interval or ratio level
D) A variable measure on the interval or ratio level and time

Question 58

The range of the coefficient of skewness is ____________.

A) Values greater than or equal to zero or always positive
B) Values less than or equal to zero or always negative
C) Both positive and negative values
D) Values between -1 and +1

Question 59

A stem-and-leaf display includes the following row: 3 | 0 1 3 5 7 9. Assume that the data is rounded to the nearest whole number. Which of the following statements is true?

A) The frequency of the class is seven.
B) The minimum value in the class is 0.
C) The maximum value in the class is 39.
D) The class interval is 5.

Question 60

A large oil company is studying the number of gallons of gasoline purchased per customer at self-service pumps. The mean number of gallons is 10.0, with a standard deviation of 3.0 gallons. The median is 10.75 gallons. What is Pearson's coefficient of skewness in this instance?

A) -1.00
B) -0.75
C) +0.75
D) +1.00

Question 61

A scatter diagram shows the ____________ between two interval or ratio variables.

Question 62

In a negatively skewed distribution, the coefficient of skewness is ______________.

Question 63

A __________ shows the interquartile range.

Question 64

A ___________ uses dots to show frequencies.

Question 65

The _____________ unit of measurement is used to express the coefficient of skewness.

Question 66

The interquartile range is the distance between ___________.

Question 67

A __________ clearly shows outliers.

Question 68

Percentiles divide a frequency distribution into _________ equal parts.

Question 69

In a symmetric distribution, is the 99^th percentile is located in the ________ tail.

Question 70

The eighth decile:

A) contains at least 70 percent of the observations.
B) is the same as the 40^th percentile.
C) is the same as the 70^th percentile.
D) is the same as the 80^th percentile.

Question 71

If the mean of a distribution is smaller than the median and mode, the sign of Pearson's coefficient of skewness is ______________.

Question 72

Which of the following is not a measure of dispersion?

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

Question 73

Pearson's coefficient of skewness (Sk) ranges from -3.0 to +3.0. It is computed by subtracting the median from the mean, multiplying the result by 3, and dividing by the _______________.

Question 74

Quartiles divide a frequency distribution into _______ equal parts.

Question 75

The 75^th percentile is referred to as the:

A) first quartile.
B) second quartile.
C) third quartile.
D) fourth quartile.

Question 76

The 67^th percentile is:

A) the value above which 67 percent of the observations occur.
B) a value one less than 67 percent of the observations.
C) the value below which 67 percent of the observations occur.
D) the value of the observation at the 67^th location.

Question 77

The ______________ is used to measure the relative symmetry of a distribution.

Question 78

A ___________ is the best way to display the relationship between two variables measured on an interval or ratio level.

Question 79

In a positively skewed distribution, the 50^th percentile is the same as the ______________.

Question 80

The coefficient of skewness measures a distribution's ____________ symmetry.