Analysis of Quantitative Data

Analysis of Quantitative Data

Now that we have reviewed the different types of variables, we need to know how we use the numeric responses to these variables. Analyzing the numeric information produces results from data. Interpreting data through analysis is key to communicating results to your stakeholders. The type of analysis you use depends on the research design, the type of variables you have, and the distribution of the data.

In this section we will focus on the two types of analysis: descriptive and inferential.

Descriptive Analysis

Descriptive analysis tells us about the basic qualities of the data. Descriptive analysis includes descriptive statistics such as the range, minimum, maximum, and frequency. It also includes measures of central tendency such as mean, median, mode, and standard deviation that tell us what our data look like.

There are many ways to describe data, and we can use descriptive analysis to tell us what the data look like. Below are some common ways to describe data. Using the set of scores below, the following table lists examples of descriptive statistics.

5 5 5 5 10 10 20 20 20


Common Descriptive Statistics

Example

Range:

The difference between the highest score and lowest score.

In the scores above, the Range = 15


Minimum (Min):

The lowest/smallest score in a data set.

In the scores above, the Min = 5

Maximum (Max):

The highest/largest score in a data set.

In the scores above, the Max = 20


Frequency:

The number of times a certain value appears.

In the scores above, the frequency of 20 is 3; expressed as a percentage, the score 20 appears 33% of the time

 

Measures of Central Tendency

The measures of central tendency can give a snapshot of how participants are responding in general. These measures include the mean, median, and mode.

5 5 5 5 10 10 20 20 20

Measures of Central Tendency

Example

Mean:

The average or the sum of the values divided by the number of values.

In the scores above the Mean = 11.1 (5+5+5+5+10+10+20+20+20)/9


Median:

The middle score of data after they are put in numerical order. To find the middle position, you order the scores, count the number of scores, add 1 and divide by 2.

In the scores above the Median = 10

Mode:

The most frequently occurring score in a data set.

In the scores above the Mode = 5

 

 

Explore Additional Resources