Deck 2: Descriptive Statistics: Understanding Distributions of Numbers

Question 1

A perfectly normal frequency distribution graph is said to be

A)positively skewed
B)negatively skewed
C)leptokurtic
D)mesokurtic
E)platykurtic

Answer 1

mesokurtic

Question 2

In a frequency distribution table where a majority of the frequencies are 1, the best solution would be to

A)group the data into intervals
B)use cumulative frequency as the dependent variable
C)use percentages instead of frequencies
D)use a frequency polygon
E)all of the above would be acceptable solutions

Answer 2

group the data into intervals

Question 3

Perhaps the oldest presentation in history of descriptive statistics was

A)a frequency distribution
B)graphs and tables
C)a frequency polygon
D)a pie chart

Answer 3

a frequency distribution

Question 4

Who used the word statistics in the English language as a method of determining a country's inhabitants' happiness?

A)De Moivre
B)Sinclair
C)Gauss
D)Galton

Question 5

To display vividly the cause of some types of ulcers, a researcher

A)cured the patient with milk and a bland diet
B)injected himself with the bacteria from a patient's ulcer
C)injected a patient with ulcers with an antibiotic
D)injected a patient without ulcers with bacteria from a patient's ulcer

Question 6

How many graphs and tables in the previous question showed the direct comparison between the number of seal failures and temperature?

A)0
B)1
C)2
D)13
E)all 25 but NASA had already made up its mind

Question 7

The main difference between a bar graph and a histogram is

A)two-dimensional bars instead of three-dimensional bars
B)vertical instead of a horizontal presentation
C)bar graphs have spaces between bars and histograms don't
D)they are identical in every aspect

Question 8

The normal curve is also called the

A)vertical frequency distribution
B)bimodal distribution
C)kurtotic curve
D)bell-shaped curve

Question 9

What did Dr.Snow do to show very effectively that his hypothesis was correct and thereby demonstrated the cause-effect relationship he advocated?

A)drank from the Broad Street well
B)removed the pump handle from the Broad Street well
C)isolated the bacteria from the Broad Street well
D)performed an autopsy on one of the victims before the city council
E)all of the above

Question 10

Currently, the best substitute for the word errors in statistics is

A)problems
B)klinkers
C)variations
D)mistakes

Question 11

A very pointed narrow frequency distribution graph is said to be

A)positively skewed
B)negatively skewed
C)leptokurtic
D)mesokurtic
E)platykurtic

Question 12

A very flat frequency distribution graph is said to be

A)positively skewed
B)negatively skewed
C)leptokurtic
D)mesokurtic
E)platykurtic

Question 13

In a study by Micceri of 440 large-sample distributions, what percentages were significantly different from the true normal distribution?

A)54%
B)79%
C)92%
D)100%

Question 14

In her bar graph presentation to the queen of England, Florence Nightingale controlled for which two rival hypotheses?

A)age and gender
B)age and ethnicity
C)age and war
D)health and conditions
E)war and gender

Question 15

In Figure 2.3 (truck brands), the major problem of the presentation was

A)cutting off the bottom 95% of the bars' heights
B)hiding the brand names of the competing trucks
C)too many useless colors
D)meaningless three-dimensional bars
E)all of the above

Question 16

Which of the following was NOT a characteristic of bad graphs according to Tufte?

A)low density
B)chart junk
C)changing scales
D)labeling badly
E)the use of only black and white in a graph

Question 17

Which of the following is NOT true about Tukey's stem-and-leaf plots?

A)presents the data horizontally instead of vertically
B)presents all of the numbers in the set
C)can result in a single stem for some data sets
D)represents missing values with 0 or 99

Question 18

What error did Florence Nightingale commit in her bar graph presentation to the queen of England?

A)interval widths were too large
B)interval widths were too small
C)overlapping interval widths
D)too many colors

Question 19

How many graphs and tables did the rocket manufacturers prepare to convince NASA that the seals in the Space Shuttle Challenger might fail in cold weather?

A)1
B)2
C)13
D)25

Question 20

A positively skewed distribution is also said to be

A)skewed normally
B)skewed left
C)skewed down
D)skewed up
E)none of the above

Question 21

For the previous set of numbers, what is the percentage of frequency of the second interval rounded to one decimal place?

A)20.7%
B)40.7%
C)40.74%
D)40.8%

Question 22

In a stem-and-leaf plot of the previous data, what would the second stem look like?

A)3 | 12345668999
B)3 | 0123456678999
C)3 | 02345668999
D)3032333435(1)36(2)38(1)39(3)

Question 23

For the following set of numbers 21, 22, 25, 25, 27, 29, 30, 32, 33, 34, 35, 36, 36, 38, 39, 39, 39, 40, 42, 44, 45, 56, 57, 59, 60, 60, 60, set up a frequency distribution table with interval widths of 10 (starting at 20-29).What is the frequency of the second interval?

A)6
B)8
C)11
D)4

Question 24

In a stem-and-leaf plot of the previous data, what would the third stem look like?

A)4 | 0245
B)40 | 1, 42 | 1, 44 | 1, 45 | 1
C)5 | 679
D)6 | 000

Question 25

For the previous set of numbers, what is the cumulative percentage, including the second interval rounded to one decimal place?

A)62.96%
B)62.9%
C)63.0%
D)62.9629%