Deck 2: Descriptive Statistics: Tabular and Graphical Methods

Question 1

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

Answer 1

True

Question 2

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 2

True

Question 3

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

Answer 3

True

Question 4

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

Question 5

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.

Question 6

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

Question 7

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

Question 8

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 9

A runs plot is a form of scatter plot.

Question 10

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

Question 11

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

Question 12

A frequency table includes row and column percentages.

Question 13

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

Question 14

A scatter plot can be used to identify outliers.

Question 15

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

Question 16

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 17

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

Question 18

The sample cumulative distribution function is nondecreasing.

Question 19

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

Question 20

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

Question 21

Row or column percentages can be found in

A) frequency tables.
B) relative frequency tables
C) cross-tabulation tables.
D) cumulative frequency tables.

Question 22

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

Question 23

Sparklines are line charts often embedded with the text where they are being discussed.

Question 24

Which of the following is the best analytic dashboard graphical method for visualizing hierarchical information?

A) bullet graph
B) sparkline
C) treemap
D) gauge

Question 25

Gauges feature a single measure showing variation over time.

Question 26

An analytic dashboard presents both current and historical trends of a business's key performance indicators.

Question 27

Treemaps are used to display qualitative measures of performance.

Question 28

Data drill down is a form of data discovery.

Question 29

If space is an issue when presenting analytic dashboard graphics,gauges should be used most frequently.

Question 30

A treemap graphic is a series of clustered rectangles.

Question 31

________ 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 32

Which of the following dashboard graphical methods will show variation over time?

A) bullet graph
B) sparkline
C) treemap
D) gauge

Question 33

A bullet graph features a single measure as either a horizontal or vertical bar.

Question 34

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

A) histogram
B) scatter plot
C) ogive plot
D) pie chart

Question 35

Which of the following is not a graphical tool for descriptive analytics (dashboards)?

A) bullet graph
B) sparkline
C) scatter plot
D) treemap
E) gauge

Question 36

As a business owner,I have requested my staff to develop a set of dashboards that can be used by the public to show wait time at each of my four local coffee shops at peak times during the day and whether the time is short,medium,or long.Which of the following graphical displays would be the best choice?

A) bullet graph
B) sparkline
C) treemap
D) gauges

Question 37

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 38

Key performance indicators are best represented by a data discovery method.

Question 39

Sparklines always need to be displayed with either their axes or coordinates.

Question 40

A(n)_____________ is a graphical presentation of the current status and historical trends of a business's key performance indicators.

A) frequence distribution
B) histogram
C) Pareto chart
D) dashboard

Question 41

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

A) large
B) small
C) integer
D) mutually exclusive
E) equal

Question 42

A ______________ shows the relationship between two variables.

A) stem-and-leaf
B) bar chart
C) histogram
D) scatter plot
E) pie chart

Question 43

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

A) bar chart
B) histogram
C) pie chart
D) Pareto chart

Question 44

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

A) absolute extreme
B) outlier
C) mode
D) quartile

Question 45

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 46

______________ 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 47

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 48

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 49

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 50

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 51

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

A) runs
B) scatter
C) dot
D) ogive

Question 52

Which of the following graphs is for qualitative data?

A) histogram
B) bar chart
C) ogive plot
D) stem-and-leaf

Question 53

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 54

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 55

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

A) bar chart
B) pie chart
C) histogram
D) pareto chart

Question 56

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

A) frequency
B) relative frequency
C) leaf
D) cumulative sum

Question 57

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 58

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 59

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 60

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 the other choices is correct.

Question 61

The number of items rejected daily by a manufacturer because of defects for the last 30 days are:
20,21,8,17,22,19,18,19,14,17,11,6,21,25,4,19,9,12,16,16,10,28,24,6,21,20,25,5,17,8
Construct a stem-and-leaf plot.

Question 62

Recently an advertising company called 200 people and asked them to identify the company that was in an ad running nationwide.They obtained the following results. Construct a table of column percentages.

Question 63

The number of items rejected daily by a manufacturer because of defects for the last 30 days are:
20,21,8,17,22,19,18,19,14,17,11,6,21,25,4,19,9,12,16,16,10,28,24,6,21,20,25,5,17,8
Complete this frequency table for these data.

Question 64

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 65

Consider the following data on distances traveled by people to visit the local amusement park. Construct an ogive plot that corresponds to the frequency table.

Question 66

Fill in the missing components of the following frequency distribution constructed for a sample size of 50.

Question 67

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
Construct an ogive plot.

Question 68

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. Construct a table of row percentages.

Question 69

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

A) frequency
B) relative frequency
C) leaf
D) cumulative percentage

Question 70

The following is a relative frequency distribution of grades in an introductory statistics course. If we wish to depict these data using a pie chart,find how many degrees (out of 360 degrees)should be assigned to each grade.

Question 71

The following is a relative frequency distribution of grades in an introductory statistics course. Construct a percent frequency bar chart for this data.

Question 72

The following is a relative frequency distribution of grades in an introductory statistics course. If this was the distribution of 200 students,give the frequency distribution for this data.

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 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 75

Consider the following data. Create a stem-and-leaf display for the sample.

Question 76

Recently an advertising company called 200 people and asked them to identify the company that was in an ad running nationwide.They obtained the following results. Construct a table of row percentages.

Question 77

The number of items rejected daily by a manufacturer because of defects for the last 30 days are:
20,21,8,17,22,19,18,19,14,17,11,6,21,25,4,19,9,12,16,16,10,28,24,6,21,20,25,5,17,8
Construct an ogive plot.

Question 78

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 79

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. Construct a table of column percentages.

Question 80

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