Deck 4: Describing Data: Displaying and Exploring Data

Question 1

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

Answer 1

False

Question 2

A dot plot is useful for showing possible outliers.

Answer 2

True

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

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

Question 5

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

Question 6

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

Question 7

A box plot shows the relative symmetry of a distribution.

Question 8

Quartiles divide a distribution into ten equal parts.

Question 9

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 10

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

Question 11

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

Question 12

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

Question 13

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

Question 14

A dot plot shows the relative symmetry of a distribution.

Question 15

Percentiles divide a distribution into one hundred equal parts.

Question 16

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

Question 17

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

Question 18

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

Question 19

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

Question 20

Quartiles divide a distribution into four equal parts.

Question 21

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 22

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 23

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.

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 24

The following graph is a

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

Question 25

Percentiles divide a distribution into

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

Question 26

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 27

In the following graph,

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 28

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

Question 29

Quartiles divide a distribution into

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

Question 30

A relationship between gender and preference for Coke or Pepsi can be best represented by a scatter diagram.

Question 31

In the following set of data, what are the first, second, and third quartiles? 1 3 5 6 7 9 100

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

Question 32

A dot plot is best applied for a data set with

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

Question 33

The following graph is a

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

Question 34

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 cumulative frequency distribution.
D) Distributed symmetrically around the mean.

Question 35

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 36

In the following graph,

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

Question 37

A dot plot shows the

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

Question 38

In a distribution, the second quartile corresponds with the

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

Question 39

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

Question 40

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 41

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 42

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 43

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 44

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 45

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

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

Question 46

Outliers are clearly presented in a

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

Question 47

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

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

Question 48

The following graph is a

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

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

What does the interquartile range describe?

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

Question 51

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 the Pearson's coefficient of skewness?

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

Question 52

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 53

The following graph is

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

Question 54

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 55

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 56

The interquartile range is graphically presented in a

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

Question 57

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 58

The following graph is a

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

Question 59

The coefficient of skewness is

A) Always positive or greater than or equal to zero.
B) Always negative or less than or equal to zero.
C) Positive, negative, or zero.
D) Unknown.

Question 60

What chart or graph uses dots to show frequencies? ________________

Question 61

The interquartile range is the distance between ___________.

Question 62

What is the best way to display the relationship between two variables measured on an interval or ratio level? _________

Question 63

What graph shows the interquartile range? ___________

Question 64

In a symmetric distribution, is the 99^th percentile located in the right or left tail? _______________

Question 65

What statistic can be used to measure the relative symmetry of a distribution? ___________________________________

Question 66

What chart or graph uses several rows of data to show a frequency distribution? _______________

Question 67

Percentiles divide a frequency distribution into _________ equal parts.

Question 68

Given the sample information in the following table regarding public opinion on gun control, who is more likely to favor gun control?

Question 69

Given the sample information in the following table regarding public opinion on gun control, what percent of Democrats have no opinion?

Question 70

The coefficient of skewness is a measure of ____________ symmetry.

Question 71

What type of graph clearly shows outliers? ___________

Question 72

What types of variables are summarized in a contingency table? ____________

Question 73

The following is an example of ____________________________

Question 74

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

Question 75

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

Question 76

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

Question 77

If the mean of a distribution is smaller than the median and mode, what is the sign of Pearson's coefficient of skewness? _______________

Question 78

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

Question 79

What unit of measurement is used to express the coefficient of skewness? _________

Question 80

Quartiles divide a frequency distribution into _______ equal parts.