Deck 2: Descriptive Statistics: Tabular and Graphical Methods

Question 1

When constructing any graphical display that utilizes categorical data,classes that have frequencies of 5 percent or less are usually combined together into a single category.

Answer 1

True

Question 2

In the first step of setting up a Pareto chart,a frequency table should be constructed of the defects (or categories)in decreasing order of frequency.

Answer 2

True

Question 3

The stem-and-leaf display is advantageous because it allows us to actually see the measurements in the data set.

Answer 3

True

Question 4

It is possible to create different interpretations of the same graphical display by simply using different captions.

Question 5

A stem-and-leaf display is a graphical portrayal of a data set that shows the data set's overall pattern of variation.

Question 6

When looking at the shape of the distribution using a stem-and-leaf,a distribution is skewed to the right when the left tail is shorter than the right tail.

Question 7

Beginning the vertical scale of a graph at a value different from zero can cause increases to look more dramatic.

Question 8

Each stem of a stem-and-leaf display should be a single digit.

Question 9

The sample cumulative distribution function is nondecreasing.

Question 10

When establishing the classes for a frequency table,it is generally agreed that the more classes you use the better your frequency table will be.

Question 11

When data are qualitative,the bars should never be separated by gaps.

Question 12

A runs plot is a form of scatter plot.

Question 13

In a Pareto chart,the bar for the "Other" category should be placed to the far left of the chart.

Question 14

A bar chart is a graphic that can be used to depict qualitative data.

Question 15

Stem-and-leaf displays and dot plots are useful for detecting outliers.

Question 16

A scatter plot can be used to identify outliers.

Question 17

The relative frequency is the frequency of a class divided by the total number of measurements.

Question 18

Splitting the stems refers to assigning the same stem to two or more rows of the stem-and-leaf display.

Question 19

When we wish to summarize the proportion (or fraction)of items in a class,we use the frequency distribution for each class.

Question 20

A frequency table includes row and column percentages.

Question 21

If there are 120 values in a data set,how many classes should be created for a frequency histogram?

A)4
B)5
C)6
D)7
E)8

Question 22

All of the following are used to describe qualitative data except the ___________.

A)Bar chart
B)Pie chart
C)Histogram
D)Pareto chart

Question 23

________ can be used to study the relationship between two variables.

A)Cross-tabulation tables
B)Frequency tables
C)Cumulative frequency distributions
D)Dot plots

Question 24

A plot of the values of two variables is a _____ plot.

A)Runs
B)Scatter
C)Dot
D)Ogive

Question 25

A ______________ can be used to differentiate the "vital few" causes of quality problems from the "trivial many" causes of quality problems.

A)Histogram
B)Scatter plot
C)Pareto chart
D)Ogive plot
E)Stem-and-leaf display

Question 26

A _____________ displays the frequency of each group with qualitative data and a _____________ displays the frequency of each group with quantitative data.

A)Histogram,stem-and-leaf display
B)Bar chart,histogram
C)Scatter plot,bar chart
D)Stem-and-leaf,pie chart

Question 27

______________ and _____________ are used to describe qualitative (categorical)data.

A)Stem-and-leaf displays,scatter plots
B)Scatter plots,histograms
C)Box plots,bar charts
D)Bar charts,pie charts
E)Pie charts,histograms

Question 28

A Stem-and-leaf display is best used to ___________.

A)Provide a point estimate of the variability of the data set
B)Provide a point estimate of the central tendency of the data set
C)Display the shape of the distribution
D)None of these

Question 29

An observation separated from the rest of the data is a(n)___________.

A)Absolute extreme
B)Outlier
C)Mode
D)Quartile

Question 30

Which of the following graphical tools is not used to study the shapes of distributions?

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

Question 31

All of the following are used to describe quantitative data except the ___________.

A)Histogram
B)Stem-and-leaf chart
C)Dot plot
D)Pie chart

Question 32

If there are 130 values in a data set,how many classes should be created for a frequency histogram?

A)4
B)5
C)6
D)7
E)8

Question 33

A(n)______ is a graph of a cumulative distribution.

A)Histogram
B)Scatter plot
C)Ogive plot
D)Pie chart

Question 34

Which one of the following graphical tools is used with quantitative data?

A)Bar chart
B)Histogram
C)Pie chart
D)Pareto chart

Question 35

Leaves on a stem-and-leaf display should be rearranged so that they are in increasing order from left to right.

Question 36

Which of the following graphs is for qualitative data?

A)Histogram
B)Bar chart
C)Ogive plot
D)Stem-and-leaf

Question 37

When grouping a large sample of measurements into classes,the ______________ is a better tool than the ___________.

A)Histogram,stem-and-leaf display
B)Box plot,histogram
C)Stem-and-leaf display,scatter plot
D)Scatter plot,box plot

Question 38

Row or column percentages can be found in

A)Frequency tables.
B)Relative frequency tables.
C)Cross-tabulation tables.
D)Cumulative frequency tables.

Question 39

When developing a frequency distribution,the class (group)intervals should be ___________.

A)Large
B)Small
C)Integer
D)Mutually exclusive
E)Equal

Question 40

A ______________ shows the relationship between two variables.

A)Stem-and-leaf
B)Bar chart
C)Histogram
D)Scatter plot
E)Pie chart

Question 41

A CFO is looking at how much of a company's resources are spent on computing.He samples companies in the pharmaceutical industry and develops the following stem-and-leaf graph. $\begin{array} { l l } 5 & 269 \\6 & 255568999 \\7 & 11224557789 \\8 & 001222458 \\9 & 02455679 \\10 & 1556 \\11 & 137 \\12 & \\13 & 255\end{array}$
What would be the first class interval for the frequency histogram?

A)5.2-6.5
B)5.2-6.0
C)5.0-6.0
D)5.2-6.6
E)5.2-6.4

Question 42

A company collected the ages from a random sample of its middle managers,with the resulting frequency distribution shown below. $\begin{array} { lc } \text { Class Interval } & \text { Frequency } \\20 \text { to } < 25 & 8 \\25 \text { to } < 30 & 6 \\30 \text { to } < 35 & 5 \\35 \text { to } < 40 & 12 \\40 \text { to } < 45 & 15 \\45 \text { to } < 50 & 7\end{array}$
What is the relative frequency for the largest interval?

A).132
B).226
C).231
D).283
E).288

Question 43

The US local airport keeps track of the percentage of flights arriving within 15 minutes of their scheduled arrivals.The stem-and-leaf plot of the data for one year is below. $\begin{array} { l l } 76 & 9 \\77 & 114 \\78 & \\79 & 07 \\80 & 88 \\81 & 2 \\82 & 1 \\83 & 88\end{array}$
In developing a histogram of these data,how many classes would be used?

A)4
B)5
C)6
D)7
E)8

Question 44

A histogram that tails out toward larger values is ___________.

A)Skewed to the left
B)Normal
C)A scatter plot
D)Skewed to the right

Question 45

If there are 30 values in a data set,how many classes should be created for a frequency histogram?

A)4
B)5
C)6
D)7
E)8

Question 46

A CFO is looking at how much of a company's resources are spent on computing.He samples companies in the pharmaceutical industry and develops the following stem-and-leaf graph. $\begin{array} { l l } 5 & 269 \\6 & 255568999 \\7 & 11224557789 \\8 & 001222458 \\9 & 02455679 \\10 & 1556 \\11 & 137 \\12 & \\13 & 255\end{array}$
What is the smallest percentage spent on R&D?

A)5.9
B)5.6
C)5.2
D)5.02
E)50.2

Question 47

A CFO is looking at how much of a company's resources are spent on computing.He samples companies in the pharmaceutical industry and develops the following stem-and-leaf graph. $\begin{array} { l l } 5 & 269 \\6 & 255568999 \\7 & 11224557789 \\8 & 001222458 \\9 & 02455679 \\10 & 1556 \\11 & 137 \\12 & \\13 & 255\end{array}$
What is the approximate shape of the distribution of the data?

A)Normal
B)Skewed to the right
C)Skewed to the left
D)Bimodal
E)Uniform

Question 48

The general term for a graphical display of categorical data made up of vertical or horizontal bars is called a(n)___________.

A)Pie chart
B)Pareto chart
C)Bar chart
D)Ogive plot

Question 49

The US local airport keeps track of the percentage of flights arriving within 15 minutes of their scheduled arrivals.The stem-and-leaf plot of the data for one year is below. $\begin{array} { l l } 76 & 9 \\77 & 114 \\78 & \\79 & 07 \\80 & 88 \\81 & 2 \\82 & 1 \\83 & 88\end{array}$
What would be the class length for creating the frequency histogram?

A)1.4
B)0.8
C)2.7
D)1.7
E)2.3

Question 50

If there are 62 values in a data set,how many classes should be created for a frequency histogram?

A)4
B)5
C)6
D)7
E)8

Question 51

The US local airport keeps track of the percentage of flights arriving within 15 minutes of their scheduled arrivals.The stem-and-leaf plot of the data for one year is below. $\begin{array} { l l } 76 & 9 \\77 & 114 \\78 & \\79 & 07 \\80 & 88 \\81 & 2 \\82 & 1 \\83 & 88\end{array}$
How many flights were used in this plot?

A)7
B)9
C)10
D)11
E)12

Question 52

A company collected the ages from a random sample of its middle managers,with the resulting frequency distribution shown below. $\begin{array} { l r } \text { Class Interval } & \text { Frequency } \\20 \text { to } < 25 & 8 \\25 \text { to } < 30 & 6 \\30 \text { to } < 35 & 5 \\35 \text { to } < 40 & 12 \\40 \text { to } < 45 & 15 \\45 \text { to } < 50 & 7\end{array}$
What would be the approximate shape of the relative frequency histogram?

A)Symmetrical
B)Uniform
C)Multiple peaks
D)Skewed to the left
E)Skewed to the right

Question 53

A flaw possessed by a population or sample unit is ___________.

A)Always random
B)A defect
C)Displayed by a dot plot
D)The cause for extreme skewness to the right

Question 54

The percentage of measurements in a class is called the ___________ of that class.

A)Frequency
B)Relative frequency
C)Leaf
D)Cumulative percentage

Question 55

The number of measurements falling within a class interval is called the ___________.

A)Frequency
B)Relative frequency
C)Leaf
D)Cumulative sum

Question 56

A company collected the ages from a random sample of its middle managers,with the resulting frequency distribution shown below. $\begin{array} { lc } \text { Class Interval } & \text { Frequency } \\20 \text { to } < 25 & 8 \\25 \text { to } < 30 & 6 \\30 \text { to } < 35 & 5 \\35 \text { to } < 40 & 12 \\40 \text { to } < 45 & 15 \\45 \text { to } < 50 & 7\end{array}$
What is the midpoint of the third class interval?

A)22.5
B)27.5
C)32.5
D)37.5
E)42.5

Question 57

A CFO is looking at how much of a company's resources are spent on computing.He samples companies in the pharmaceutical industry and develops the following stem-and-leaf graph. $\begin{array} { l l } 5 & 269 \\6 & 255568999 \\7 & 11224557789 \\8 & 001222458 \\9 & 02455679 \\10 & 1556 \\11 & 137 \\12 & \\13 & 255\end{array}$
What would be the class length used in creating a frequency histogram?

A)1.4
B)8.3
C)1.2
D)1.7
E)0.9

Question 58

A relative frequency curve having a long tail to the right is said to be ___________.

A)Skewed to the left
B)Normal
C)A scatter plot
D)Skewed to the right

Question 59

A CFO is looking at how much of a company's resources are spent on computing.He samples companies in the pharmaceutical industry and develops the following stem-and-leaf graph. $\begin{array} { l l } 5 & 269 \\6 & 255568999 \\7 & 11224557789 \\8 & 001222458 \\9 & 02455679 \\10 & 1556 \\11 & 137 \\12 & \\13 & 255\end{array}$
If you were creating a frequency histogram using these data,how many classes would you create?

A)4
B)5
C)6
D)7
E)8

Question 60

A graphical portrayal of a quantitative data set that divides the data into classes and gives the frequency of each class is a(n)___________.

A)Ogive plot
B)Dot plot
C)Histogram
D)Pareto chart
E)Bar chart

Question 61

Recently an advertising company called 200 people and asked them to identify the company that was in an ad running nationwide.The following results were obtained. $\begin{array} { | l | c | c | c | } \hline & \text { Female } & \text { Male } & \text { Total } \\\hline \text { Correctly recalled the company } & 66 & 50 & 116 \\\hline \text { Incorrectly recalled the company } & 44 & 40 & 84 \\\hline \text { Total } & 110 & 90 & 200 \\\hline\end{array}$
What percentage of those surveyed were female and could not recall the company?

A)40.0
B)22.0
C)52.4
D)66.7
E)37.9

Question 62

Using the following data,what would be the range of the values of the stem in a stem-and-leaf display? $\begin{array}{llllllll}\text { 1. } & 11.5 & 6 . & 13.7 & 11 . & 11.0 & 16 . & 14.5 \\\text { 2. } & 13.5 & 7 . & 14.0 & 12 . & 13.0 & 17 . & 15.5 \\\text { 3. } & 12.5 & 8 . & 12.0 & 13 . & 16.7 & 18 . & 13.0 \\\text { 4. } & 15.2 & 9 . & 12.7 & 14 . & 12.5 & 19 . & 18.2 \\\text { 5. } & 14.7 & 10 . & 12.5 & 15 . & 11.5 & 20 . & 11.7\end{array}$

A)11-17
B)11-18
C)10-18
D)12-17
E)12-18

Question 63

The number of weekly sales calls by a sample of 25 pharmaceutical salespersons is below.
24,56,43,35,37,27,29,44,34,28,33,28,46,31,38,41,48,38,27,29,37,33,31,40,50
What is the shape of the distribution of the data?

A)Skewed with tail to the right
B)Skewed with tail to the left
C)Normal
D)Bimodal

Question 64

The following is a relative frequency distribution of grades in an introductory statistics course. $\begin{array}{|l|c|}\hline \text { Grade } & \text { Relative Frequency } \\\hline \text { A } & .22 \\\hline \text { B } & ? \\\hline \text { C } & .18 \\\hline \text { D } & .17 \\\hline \text { F } & .06 \\\hline\end{array}$
If this was the distribution of 200 students,find the frequency for the highest two grades.

A)44
B)118
C)59
D)74
E)35

Question 65

At the end of their final exam,550 students answered an additional question in which they rated their instructor's teaching effectiveness,with the following results. $\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\text { Student's Rating of Instructor }$
$\begin{array} { | c | c | c | } \hline \begin{array} { c } \text { Student's } \\\text { Final Grade }\end{array} & \text { Very or Somewhat Effective } & \text { Very or Somewhat Ineffective } \\\hline \text { A } & 190 & 85 \\\hline \text { B } & 75 & 120 \\\hline \text { C } & 20 & 17 \\\hline \text { D } & 9 & 18 \\\hline \text { F } & 1 & 15 \\\hline\end{array}$
What proportion of all 550 students received less than a C?

A)0.03
B)0.06
C)0.08
D)0.13
E)0.15

Question 66

As a general rule,when creating a stem-and-leaf display,there should be ______ stem values.

A)Between 3 and 10
B)Between 1 and 100
C)No fewer than 20
D)Between 5 and 20

Question 67

A local electronics retailer recently conducted a study on purchasers of large screen televisions.The study recorded the type of television and the credit account balance of the customer at the time of purchase.They obtained the following results. $\begin{array} { | l | c | c | c | c | } \hline \begin{array} { l } \text { Credit } \\\text { Balance }\end{array} & \text { Standard TV } & \text { LCD } & \text { Plasma } & \text { Projection } \\\hline \text { Under \$200 } & 10 & 16 & 40 & 5 \\\hline \$ 200 - \$ 800 & 8 & 12 & 24 & 15 \\\hline \text { Over \$800 } & 16 & 12 & 16 & 30 \\\hline \text { Total } & 34 & 40 & 80 & 50 \\\hline\end{array}$
What percentage of purchases were plasma televisions by customers with the smallest credit balances?

A)50.00
B)39.20
C)56.30
D)34.80
E)19.60

Question 68

Using the following data,what would be the leaf unit in a stem-and-leaf display? $\begin{array}{llllllll}\text { 1. } & 11.5 & 6 . & 13.7 & 11 . & 11 & 16 . & 14.5 \\\text { 2. } & 13.5 & 7 . & 14 & 12 . & 13 & 17 . & 15.5 \\\text { 3. } & 12.5 & 8 . & 12 & 13 . & 16.7 & 18 . & 13 \\\text { 4. } & 15.2 & 9 . & 12.7 & 14 . & 12.5 & 19 . & 18.2 \\\text { 5. } & 14.7 & 10 . & 12.5 & 15 . & 11.5 & 20 . & 11.7\end{array}$

A)1.0
B)10
C).10
D).01
E).20

Question 69

A local electronics retailer recently conducted a study on purchasers of large screen televisions.The study recorded the type of television and the credit account balance of the customer at the time of purchase.They obtained the following results. $\begin{array} { | l | c | c | c | c | } \hline \begin{array} { l } \text { Credit } \\\text { Balance }\end{array} & \text { Standard TV } & \text { LCD } & \text { Plasma } & \text { Projection } \\\hline \text { Under \$200 } & 10 & 16 & 40 & 5 \\\hline \$ 200 - \$ 800 & 8 & 12 & 24 & 15 \\\hline \text { Over \$800 } & 16 & 12 & 16 & 30 \\\hline \text { Total } & 34 & 40 & 80 & 50 \\\hline\end{array}$
What percentage of the customers had the highest credit balances and purchased an LCD television?

A)36.30
B)5.90
C)19.60
D)56.30
E)16.20

Question 70

The following is a relative frequency distribution of grades in an introductory statistics course. $\begin{array}{|l|c|}\hline \text { Grade } & \text { Relative Frequency } \\\hline \text { A } & .22 \\\hline \text { B } & ? \\\hline \text { C } & .18 \\\hline \text { D } & .17 \\\hline \text { F } & .06 \\\hline\end{array}$
If this was the distribution of 200 students,find the frequency of failures.

A)12
B)6
C)23
D)46
E)3

Question 71

Recently an advertising company called 200 people and asked them to identify the company that was in an ad running nationwide.The following results were obtained. $\begin{array} { | l | c | c | c | } \hline & \text { Female } & \text { Male } & \text { Total } \\\hline \text { Correctly recalled the company } & 66 & 50 & 116 \\\hline \text { Incorrectly recalled the company } & 44 & 40 & 84 \\\hline \text { Total } & 110 & 90 & 200 \\\hline\end{array}$
What percentage of those surveyed could not correctly recall the company?

A)58.00
B)56.89
C)55.00
D)43.10
E)42.00

Question 72

Using the following data,describe the shape of the data distribution. $\begin{array}{llllllll}\text { 1. } & 11.5 & 6 . & 13.7 & 11 . & 11.0 & 16 . & 14.5 \\\text { 2. } & 13.5 & 7 . & 14.0 & 12 . & 13.0 & 17 . & 15.5 \\\text { 3. } & 12.5 & 8 . & 12.0 & 13 . & 16.7 & 18 . & 13.0 \\\text { 4. } & 15.2 & 9 . & 12.7 & 14 . & 12.5 & 19 . & 18.2 \\\text { 5. } & 14.7 & 10 . & 12.5 & 15 . & 11.5 & 20 . & 11.7\end{array}$

A)Skewed to the left
B)Bimodal
C)Normal
D)Skewed to the right

Question 73

A very simple graph that can be used to summarize a quantitative data set is called a(n)___________.

A)Runs plot
B)Ogive plot
C)Dot plot
D)Pie chart

Question 74

A histogram that tails out toward smaller values is ___________.

A)Skewed to the left
B)Normal
C)A scatter plot
D)Skewed to the right

Question 75

At the end of their final exam,550 students answered an additional question in which they rated their instructor's teaching effectiveness,with the following results. $\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\text { Student's Rating of Instructor }$
$\begin{array} { | c | c | c | } \hline \begin{array} { c } \text { Student's } \\\text { Final Grade }\end{array} & \text { Very or Somewhat Effective } & \text { Very or Somewhat Ineffective } \\\hline \text { A } & 190 & 85 \\\hline \text { B } & 75 & 120 \\\hline \text { C } & 20 & 17 \\\hline \text { D } & 9 & 18 \\\hline \text { F } & 1 & 15 \\\hline\end{array}$
What proportion of the students who rated their instructor as very or somewhat effective received a B or better in the class?

A)0.345
B)0.254
C)0.482
D)0.898
E)0.644

Question 76

Consider the following data on distances traveled by people to visit the local amusement park and calculate the relative frequency for the shortest distance. $\begin{array}{|l|c|}\hline \text { Distance } & \text { Frequency } \\\hline 1-8 \text { miles } & 15 \\\hline 9-16 \text { miles } & 12 \\\hline 17-24 \text { miles } & 7 \\\hline 25-32 \text { miles } & 5 \\\hline 33-40 \text { miles } & 1 \\\hline\end{array}$

A).375
B).150
C).500
D).300
E).333

Question 77

Consider the following data on distances traveled by people to visit the local amusement park and calculate the relative frequency for the distances over 24 miles. $\begin{array}{|l|c|}\hline \text { Distance } & \text { Frequency } \\\hline 1-8 \text { miles } & 15 \\\hline 9-16 \text { miles } & 12 \\\hline 17-24 \text { miles } & 7 \\\hline 25-32 \text { miles } & 5 \\\hline 33-40 \text { miles } & 1 \\\hline\end{array}$

A).375
B).150
C).125
D).025
E).325

Question 78

An example of manipulating a graphical display to distort reality is ___________.

A)Starting the axes at zero
B)Making the bars in a histogram equal widths
C)Stretching the axes
D)Starting the axes at zero and Stretching the axes

Question 79

The number of weekly sales calls by a sample of 25 pharmaceutical salespersons is below.
24,56,43,35,37,27,29,44,34,28,33,28,46,31,38,41,48,38,27,29,37,33,31,40,50
How many classes should be used in the construction of a histogram?

A)4
B)6
C)10
D)5
E)2

Question 80

The following is a partial relative frequency distribution of grades in an introductory statistics course. $\begin{array}{|l|c|}\hline \text { Grade } & \text { Relative Frequency } \\\hline \text { A } & .22 \\\hline \text { B } & ? \\\hline \text { C } & .18 \\\hline \text { D } & .17 \\\hline \text { F } & .06 \\\hline\end{array}$
Find the relative frequency for the B grade.

A).78
B).27
C).65
D).37
E).47