Organizing Qualitative Data

Section 2.1 Organizing Qualitative Data

Definition 2.1.1. frequency distribution.

lists each category of data and the number of occurrences for each category.

Definition 2.1.2. relative frequency distribution.

lists each category of data and the proportion (or percent) of observations in that category.

relative frequency = count/total

Definition 2.1.3. pie chart.

is a circle divided into sectors. Each sector represents a category of data and its area is proportional to the frequency.

Figure 2.1.4. Crash Course Statistics: Data Visualization Part 1

Reading Questions Favorite Day to Eat Out

A survey was conducted by Wakefield Research in which 40 participants were asked to give their favorite night to go out to dinner. The following data are the results.

Thursday	Saturday	Friday	Friday	Sunday
Wednesday	Saturday	Friday	Tuesday	Friday
Saturday	Monday	Friday	Friday	Sunday
Friday	Tuesday	Wednesday	Saturday	Friday
Wednesday	Monday	Wednesday	Wednesday	Friday
Friday	Wednesday	Thursday	Tuesday	Friday
Tuesday	Saturday	Friday	Tuesday	Friday
Saturday	Saturday	Saturday	Sunday	Friday

Table 2.1.5. Data from Wakefield Research

1.

Construct a frequency distribution.

Day	Tally	Frequency
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sum:

Table 2.1.6. Favorite night to eat out frequency distribution

Solution

Day	Frequency
Sunday	3
Monday	2
Tuesday	5
Wednesday	6
Thursday	2
Friday	14
Saturday	8
Sum:	40

Table 2.1.7. Favorite night to eat out frequency distribution

2.

Construct a relative frequency distribution.

Day	Relative Frequency
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sum:

Table 2.1.8. Favorite night to eat out relative frequency distribution template

Solution

Day	Relative Frequency
Sunday	0.075
Monday	0.050
Tuesday	0.125
Wednesday	0.150
Thursday	0.050
Friday	0.350
Saturday	0.200
Sum:	1.000

Table 2.1.9. Favorite night to eat out relative frequency distribution

3.

Construct a frequency bar chart.

Solution

Figure 2.1.10. Favorite night to eat out bar chart

4.

Construct a relative frequency bar chart.

Solution

Figure 2.1.11. Favorit night to eat out pie chart

5.

Construct a pie chart.

Solution

Figure 2.1.12. Favorite night to eat out pie chart

6.

If you own a restaurant, which days would you purchase an advertisement on the local radio? Are there days that you should avoid?

Answer

It would be good to advertise on Fridays and Saturdays, but not so worthwhile to advertise on Mondays and Thursdays.