Deck 3: Graphical Descriptive Techniques 2

Question 1

Experience shows that few students hand in their statistics exams early; most prefer to hand them in near the end of the test period.This means the time taken by students to write exams is positively skewed.

Answer 1

False

Question 2

Which of the following describes the shape of the histogram below?

A)Positively skewed
B)Negatively skewed
C)Symmetric
D)None of these choices

Answer 2

Symmetric

Question 3

When a distribution has more values to the right and tails to the left,we say it is skewed negatively.

Answer 3

True

Question 4

When a distribution has more values to the left and tails off to the right,it is skewed negatively.

Question 5

The number of class intervals in a histogram depends on the number of observations in the data set.

Question 6

A histogram is said to be symmetric if,when we draw a vertical line down the center of the histogram the two sides are nearly identical.

Question 7

The number of observations within each class may be found in a frequency distribution.

Question 8

The sum of relative frequencies in a distribution always equals 1.

Question 9

A relative frequency distribution describes the proportion of data values that fall within each category.

Question 10

In a histogram,each observation is assigned to one or more classes.

Question 11

The intervals (classes)in a histogram do not overlap.

Question 12

The original observations cannot be determined once they are grouped into a frequency distribution.

Question 13

Which of the following represents a graphical presentation of interval data?

A)A bar chart.
B)A histogram.
C)A pie chart.
D)All of these choices are true.

Question 14

A skewed histogram is one with a long tail extending either to the right or left.

Question 15

The graph below is an example of a histogram.

Question 16

A modal class is the class with the largest number of observations.

Question 17

A histogram represents interval data.

Question 18

Which of the following statements about histograms is true?

A)A histogram is a summary of interval data.
B)A histogram is made of a series of intervals,called classes.
C)The classes in a histogram cover the complete range of observations.
D)All of these choices are true.

Question 19

The intervals (classes)in a histogram are equally wide.

Question 20

Which of the following statements about histograms is false?

A)The intervals of a histogram do not overlap.
B)Every observation is assigned to one and only one class in a histogram.
C)The intervals of a histogram are equally wide.
D)None of these choices.

Question 21

We create a frequency distribution for interval data by counting the number of observations that fall into each of a series of intervals,called ____________________.

Question 22

The relative frequency of a class in a histogram is computed by

A)dividing the frequency of the class by the number of classes.
B)dividing the frequency of the class by the class width.
C)dividing the frequency of the class by the total of all frequencies.
D)None of these choices.

Question 23

A histogram is said to be ____________________ if,when we draw a vertical line down the center of the histogram,the two sides are identical in shape and size.

Question 24

Which of the following statements about shapes of histograms is true?

A)A histogram is said to be symmetric if,when we draw a vertical line down the center of the histogram,the two sides are identical in shape and size.
B)A negatively skewed histogram is one with a long tail extending to the left.
C)A positively skewed histogram is one with a long tail extending to the right.
D)All of these choices are true.

Question 25

We determine the approximate width of the classes by subtracting the smallest observation from the largest and dividing the answer by the number of ____________________.

Question 26

A(n)____________________ is a table that sorts data into class intervals (categories)and gives the number of observations in each interval (category).

Question 27

Compare the spread of the two histograms below.Which of the following is true?

A)Data Set A has a larger spread than Data Set B.
B)Data Set A has a smaller spread than Data Set b.
C)Data Set A has the same spread as Data Set B.
D)You cannot compare the spreads of these histograms without the original data.

Question 28

Compare the two histograms below.Which statement is true?

A)The spread of histogram A is smaller than the spread of histogram B.
B)The spread of histogram A is larger than the spread of histogram b.
C)The spread of histogram A is the same as the spread of histogram B.
D)You cannot compare the spreads of these two histograms without the original data.

Question 29

A(n)____________________ histogram is one with a long tail extending to either the right or the left.

Question 30

In a histogram a(n)____________________ class is the one with the largest number of observations.

Question 31

A modal class in a histogram is the class that includes

A)the largest number of observations.
B)the smallest number of observations.
C)the largest observation in the data set.
D)the smallest observation in the data set.

Question 32

The sum of the relative frequencies for all classes in a histogram always equals

A)the number of classes.
B)the class width.
C)the total of all the frequencies.
D)one.

Question 33

It is typical that when taking an exam,few students hand in their exams early; most prefer to reread their papers and hand them in near the end of the scheduled exam period.Under this scenario,a histogram of exam taking times is ____________________ skewed.

Question 34

The histogram below has a shape that is ____________________.

Question 35

For what type of data is a histogram appropriate?

Question 36

Compare the two histograms below.Which statement is true?

A)The center of histogram A is lower than the center of histogram B.
B)The center of histogram A is higher than the center of histogram b.
C)The center of histogram A is the same as the center of histogram B.
D)You cannot compare the centers of these two histograms without the original data.

Question 37

A(n)____________________ histogram has two peaks,not necessarily equal in height.

Question 38

A graph of the frequency distribution for interval data is called a(n)____________________.

Question 39

Compare the two histograms below.Which statement is true?

A)The shape of histogram A is the same as the shape of histogram B.
B)The shape of histogram A is positively skewed compared to histogram b.
C)The shape of histogram A is negatively skewed compared to histogram B.
D)You cannot compare the shapes of these two histograms without the original data.

Question 40

The more observations we have,the ____________________ the number of class intervals we need to use to draw a useful histogram.

Question 41

Electronics Company At a meeting of regional offices managers of a national electronics company,a survey was taken to determine the number of employees the regional managers supervise in the operation of their departments.The results of the survey are shown below. ​ ​ ​
{Electronics Company Narrative} What proportion of managers supervises 3 employees?

Question 42

{Test Grades Narrative} Describe the distribution of exam scores.

Question 43

{Test Grade Narrative} Construct a relative frequency histogram for this data set and discuss its shape.

Question 44

{Test Grades Narrative} Construct frequency and relative frequency distributions for this data set using seven class intervals.Describe the shape of the data set.

Question 45

Insurance Company A representative from a local insurance agency selected a random sample of insured homeowners and recorded the number of claims made in the last three years,with the following results: ​ ​ ​ ​
{Insurance Company Narrative} How many homeowners are represented in the sample?

Question 46

Insurance Company A representative from a local insurance agency selected a random sample of insured homeowners and recorded the number of claims made in the last three years,with the following results: ​ ​ ​ ​
{Insurance Company Narrative} How many total claims are represented in the sample?

Question 47

{Teachers Ages Narrative} Draw a frequency histogram of this data which contains six classes.What is the shape of the histogram?

Question 48

A supermarket's monthly sales (in thousands of dollars)for the last year were as follows: Construct a relative frequency bar chart for this data set.How many observations are there in this data set?

Question 49

Electronics Company At a meeting of regional offices managers of a national electronics company,a survey was taken to determine the number of employees the regional managers supervise in the operation of their departments.The results of the survey are shown below. ​ ​ ​
{Electronics Company Narrative} Across all of the regional offices,how many total employees were supervised by those surveyed?

Question 50

Electronics Company At a meeting of regional offices managers of a national electronics company,a survey was taken to determine the number of employees the regional managers supervise in the operation of their departments.The results of the survey are shown below. ​ ​ ​
{Electronics Company Narrative} How many regional offices are represented in the survey results?

Question 51

The graph below represents a line graph.

Question 52

Insurance Company A representative from a local insurance agency selected a random sample of insured homeowners and recorded the number of claims made in the last three years,with the following results: ​ ​ ​ ​
{Insurance Company Narrative} What proportion of homeowners had no claims in the last three years?

Question 53

Thirty voters participating in a recent election exit poll in Alabama were asked to state their political party affiliation.Coding the data 1 for Republican,2 for Democrat,and 3 for Independent,the data collected were as follows: 3,1,2,3,1,3,3,2,1,3,3,2,1,1,3,2,3,1,3,2,3,2,1,1,3,1,2,2,1,and 3.Develop a frequency distribution and a relative frequency distribution for this data.What does the data suggest about the strength of the political parties in Alabama?

Question 54

{Teachers Ages Narrative} Draw a frequency histogram of this data which contains four classes.What is the shape of the histogram?

Question 55

A line chart is created by plotting the values of the variable on the vertical axis and the time periods on the horizontal axis.

Question 56

Electronics Company At a meeting of regional offices managers of a national electronics company,a survey was taken to determine the number of employees the regional managers supervise in the operation of their departments.The results of the survey are shown below. ​ ​ ​
{Electronics Company Narrative} What is the cumulative relative frequency corresponding to 4 employees?

Question 57

Fifty two truck buyers were asked to indicate the car dealer they believed offered the best overall service.The four choices were A,B,C,and D as shown below: Construct a table showing the frequencies and relative frequencies for this data set.What proportion of car buyers rated dealer D as the best?

Question 58

Insurance Company A representative from a local insurance agency selected a random sample of insured homeowners and recorded the number of claims made in the last three years,with the following results: ​ ​ ​ ​
{Insurance Company Narrative} What number of claims was made by the highest proportion of homeowners?

Question 59

Time series data are often graphically depicted on a line chart,which is a plot of the variable of interest over time.

Question 60

A line chart that is flat shows no fluctuation in the variable being presented.

Question 61

Observations that are measured at the same time represent what type of data?

A)Time-series data
B)Cross-sectional data
C)Synchronous data
D)None of these choices.

Question 62

Briefly discuss the difference between cross-sectional data and time-series data.

Question 63

Time series data are often graphically depicted on a(n)____________________,which is a plot of the variable of interest over time.

Question 64

A(n)____________________ is created by plotting the value of the variable on the vertical axis and the time periods on the horizontal axis.

Question 65

The line chart below shows potato prices per pound for each month from January (month 1)to December last year.By looking at this chart you can see the lowest potato prices occurred in ____________________.

Question 66

A line chart is created by plotting the value of the variable on the ____________________ axis and the time periods on the ____________________ axis.

Question 67

Beef prices throughout the year (month 1 = January)are shown in the line chart below (per pound).Describe beef prices for this given year using this line chart.

Question 68

Explain the difference between a histogram and a line chart.

Question 69

A department store's monthly sales (in thousands of dollars)for the last year were as follows.A histogram should be used to present these data.

Question 70

Observations that are measured at successive points in time is what type of data?

A)Time-series data
B)Cross-sectional data
C)Successive data
D)None of these choices.

Question 71

What type of graph depicts the data below?

A)A line chart
B)A histogram
C)A dot plot
D)A bar chart

Question 72

The line chart below shows tomato prices each month from January (month 1)to December last year ($ per pound).By looking at this chart you can see the lowest tomato prices occurred in July.

Question 73

Which of the following statements describe(s)the line chart below?

A)November experienced the lowest sales throughout the year.
B)August experienced the highest sales throughout the year.
C)Sales did not fluctuate more than 30 units on either side of 90.
D)All of these choices are true.

Question 74

Observations that are taken during successive points in time are called ____________________ data.

Question 75

Observations that are measured at the same time are called ____________________ data.

Question 76

Which of the following statements describes a line chart?

A)A line chart is a graph of time-series data.
B)A line chart is a plot of a variable over time.
C)The horizontal axis of a line chart contains time periods.
D)All of these choices are true.

Question 77

Time-series data are often graphically depicted how?

A)Bar chart
B)Histogram
C)Line chart
D)All of these choices are true.

Question 78

The line chart below shows cucumber prices fluctuated from $2.00 per pound to over $4.50 per pound during the year.

Question 79

What kind(s)of data can be depicted by a line chart?

A)Frequencies of an interval over time.
B)Frequencies of a nominal variable over time.
C)Relative frequencies of a nominal variable over time.
D)All of these choices are true.

Question 80

Which of the following represents time-series data?

A)The length of time each of the top 100 stocks have been available on the NYSE.
B)The most popular time of year that people purchase the top 100 stocks on the NYSE.
C)The value of the #1 stock on the NYSE each month over a one-year period.
D)All of these choices are true.