Qualitative Data Types, Lecture notes of Statistics

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QUALITATIVE DATA

Module One

Lesson Four

This presentation is based on material and graphs from OpenStax and is copyrighted by OpenStax and Georgia Highlands College

Introduction ■ RECALL: From module one, lesson two, QUALITATIVE DATA involves labels or descriptions of traits using words or phrases ■ To ultimately answer a research question, a researcher must organize the data in some meaningful way.

• Frequency Distributions (Table) ■ After organizing the data, the researcher must display them in an understandable way to his “audience”
• Graphs ■ This lesson explains how to organize and display qualitative data using the above mentioned tools.

Categorical Frequency Distribution ■ is the organization of qualitative raw data in table form ■ lists the categories alphabetically

• categories or groups are called a “CLASS” ■ has 3 to 4 columns
• Categories (Class)
• Tally (tick marks to indicate class has occurred in raw data, optional)
• Frequency, f – number of times class occurs within entire data set, written as a whole number
• Relative frequency---proportion of class that occurs within entire data set, written as a percentage, best value to use when comparing data sets of different sizes, use the formula: 𝑓𝑟𝑒𝑞𝑢𝑒𝑛𝑐𝑦,𝑓 𝑠𝑎𝑚𝑝𝑙𝑒 𝑠𝑖𝑧𝑒,𝑛

■ can be “jumpstart” for graphs

Example: What is the most popular county of residence of Georgia Highlands College students enrolled in Spring 2016? ■ The variable is the county of residence

• Qualitative, neither discrete or continuous, nominal ■ The population is all Georgia Highlands College students enrolled in Spring 2016 ■ The sample is all students enrolled in 4 different sections of MATH 2200 at GHC in Spring 2016 on the Cartersville campus
• Sampling method: Cluster
• Random
• Representative? Only GHC students from Cartersville campus were surveyed. It would be better to have some students from each GHC campus, including online

County of Residence Tally Frequency, f Relative Frequency Bartow Cherokee Cobb Gordon Paulding TOTAL

County of Residence Tally Frequency, f Relative Frequency Bartow IIII IIII IIII IIII I Cherokee IIII II Cobb IIII IIII I Gordon II Paulding IIII IIII TOTAL Sample size, n = 50

County of Residence Tally Frequency, f Relative Frequency Bartow IIII IIII IIII IIII I 21 21 50 ∗ 100% = 42% Cherokee IIII II 7 7 50 ∗ 100% = 14% Cobb IIII IIII I 11 11 50 ∗ 100% = 22% Gordon II 2 2 50 ∗ 100% = 4% Paulding IIII IIII 9 9 50 ∗ 100% = 18% TOTAL Sample size, n = 50 Sample Size, n = 50 (^) 100%

■ We could at this point answer the research question, BUT graphs are even more useful for providing a lot of information quickly to a reader. ■ Newspapers and the Internet use graphs to show trends and to enable readers to compare facts and figures quickly. ■ Although there are no strict rules about which graphs to use, the information to be shared can determine the best graph to use. ■ For qualitative data, we will focus on two different graphs

• Bar Graph
• Pie Chart
• NOTE: You do not have to create these graphs, but will be asked to interpret the information provided by the graphs.

County of Residence Tally Frequency, f Relative Frequency Bartow IIII IIII IIII IIII I 21 21 50 ∗ 100% = 42% Cherokee IIII II 7 7 50 ∗ 100% = 14% Cobb IIII IIII I 11 11 50 ∗ 100% = 22% Gordon II 2 2 50 ∗ 100% = 4% Paulding IIII IIII 9 9 50 ∗ 100% = 18% TOTAL Sample size, n = 50 Sample Size, n = 50 (^) 100%

GRAPHS ■ the height (or length) of the bar represents the FREQUENCY of the category ■ “gaps” between the bars, since each category is a “stand-alone” ■ should have a title with details Bar Graphs 21 7 11 2 9 0 5 10 15 20 25 Bartow Cherokee Cobb Gordon Paulding Number of Students County of Residence County of Residence for GHC Students Spring 2016

ANALYSIS OF

QUALITATIVE DATA

What can we learn from the sample about the population? ■ Analyses options are limited with qualitative data (words, phrases) ■ Researchers are able to determine:

• Most (called the MODE)
• Least
• Rankings (order)

EXAMPLE

Qualitative Data

Q: What is the most popular type of computer sold at a local retail store? ■ NOTE: A local retail store could be Office Depot, Staples, Target, Wal-Mart, Best Buy, etc. This process can be used by “real- world” retailers to analyze their sales

■ The variable is the type of computer sold to a customer at a local retail store.

Options are Desktop, laptop, notebook, or tablet.

• Qualitative, neither discrete or continuous, nominal

■ The population is all computers sold to customers at a local retail store

■ The sample was collected using sales records from the past year. A random

starting point was selected and every 7

th

record examined.

• Systematic sampling
• Random
• Representative