Unit 1

Question 1

Which one of the following is always true about a histogram?
Which one of the following is always true about a histogram?
A) It is exactly the same as a bar graph.
B) The shape depends on the total number of date values.
C) Accurate histograms can display either cut-points or midpoints of the interval.
D) The area under a histogram is 1.
E) It is bell-shaped

Answer 1

C) Accurate histograms can display either cut-points or midpoints of the interval.

Question 2

Dot plots
A) Are generally used for either discrete or continuous data
B) Do not indicate spread of data as well as histograms
C) Do not indicate spread of data as well as stem and leaf plots
D) Are excellent plots for discrete data sets.
E) Are effective for displaying center and spread of data but not for displaying shape.

Answer 2

D) Are excellent plots for discrete data sets.

Question 3

It is easiest to determine quartiles of a data set when viewing
A) The histogram
B) The dot plot
C) The stem and leaf plot
D) the bar graph
E) Quartiles cannot be determined using any of these plots

Answer 3

C) The stem and leaf plot.

Question 4

Given the first type of plot indicated in each pair, which of the second plots could not always be generated from it?
A) dot plot -> histogram
B) stem and leaf -> dot plot
C) dot plot -> box plot
D) histogram -> stem and leaf plot
E) All of these can always be generated

Answer 4

D) histogram -> stem and leaf plot

Question 5

Which is true of a box plot?
A) One must have a box but may be missing one or both whiskers.
B) It is possible to have a box plot with no box or whiskers.
C) It is possible to determine the data values if you only have a box plot.
D) If there is one outlier, then there are at least two whiskers.
E) One must have whiskers but may be missing a box.

Answer 5

B) It is possible to have a box plot with no box or whiskers.
For example, construct a box plot for the set {5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5}.

Question 6

If the largest value of a large data set is doubled, which of the following is true?
A) The mean remains the same
B) The standard deviation remains the same
C) The interquartile range remains the same.
D) The range remains the same
E) The median increases

Answer 6

C) The interquartile range remains the same.

Question 7

If the test scores of a class of 30 students have a mean of 75.6 and the test scores of another class of 24 students have a mean of 68.4, then the mean of the combined group is
A) 72
B) 72.4
C) 72.8
D) 74.2
E) 75

Answer 7

B) 72.4

Question 8

What’s the five-number summary of a set of data?

Answer 8

five number summary

1. minimum value
2. Q1
3. Median
4. Q3
5. Maximum

Question 9

What’s the difference between describing the distribution of data and comparing the distribution of data?

Answer 9

1. for both, use CUSS

2. for comparing the distributions of data, mention how they relate to each other.

Question 10

What’re individuals?

Answer 10

individuals are objects described by a set of data.

Question 11

What can individuals be?

Answer 11

individuals can be:

1. people
2. animals
3. things

Question 12

What’s a distribution?

Answer 12

the distribution is what values the variable takes, and how often it takes those values

Question 13

What does a frequency table display?

Answer 13

a frequency table displays the number and frequency of each variable/ category

Question 14

What does a relative frequency table display?

Answer 14

a relative frequency table displays what percentage of the total data set each variable/category takes up.

Question 15

What’s an association between two variables?

Answer 15

an association between two variables is when specific values of one variable tend to occur in common with specific values of another variable

Question 16

Why’s it beneficial to split the stems on a stemplot?

Answer 16

it’s beneficial to split the stems on a stemplot so you can see the DISTRIBUTION better

Question 17

When do you use a back to back stemplot?

Answer 17

use a back to back stemplot when you are comparing the values of two variables or categories.

Question 18

What’s the most common measure of center?

Answer 18

the mean is the most common measure of center

Question 19

what does the z-score tell you?

Answer 19

the z-score tells you how many standard deviations a value is from the mean, and in what direction.

Question 20

What measures of center and spread are better to find?

Answer 20

median and IQR are better to find because they’re RESISTANT to extreme values!

Question 21

What can a cumulative relative frequency graph be used to describe?

Answer 21

1. the position of an individual within a distribution

2. to locate a specific percentile of the distribution.