Lesson 5

Question 1

Qualitative data is often summarized by contracting tables called..

Answer 1

frequency tables, to see how many times a variable has certain values

Question 2

In addition to the frequency, we may
be interested in the relative
frequency which is..

Answer 2

the proportion (or
percentage) of the total that falls
into each category.

Question 3

If the variable has a natural ordering,
we may want to know the

Answer 3

cumulative frequency. Cumulative
frequency counts how often an
observation falls into each category
OR any of the categories before it.

Question 4

We can combine the ideas of relative
frequency and cumulative frequency
to get a

Answer 4

This is the proportion (or
percentage) of observations in the
current category or the categories
before it.

Question 5

How could I calculate cumulative
relative frequency?

Answer 5

Option 1: Add up the relative
frequencies as I go like I did when
calculating cumulative frequency.
Option 2: Divide the cumulative
frequencies by the total (28).

Question 6

Sometimes people will make frequency tables
for quantitative data too. When they do this, the
create “bins” of values so that the variable looks
qualitative.

Answer 6

For example, if I have the variable income, I could
create categories of
* $0 - $50,000
* $50,000 - $100,000
* $100,000 - $150,000
* etc.
Note: Bins are made with equal length in each. In
other words, it should have the same amount of
increment for all bins.