What are quantitative and qualitative data?
Quantitative data are measures of values or counts and are expressed as numbers.
Quantitative data are data about numeric variables (e.g. how many; how much; or how often).
Qualitative data are measures of ‘types’ and may be represented by a name, symbol, or a number code.
Qualitative data are data about categorical variables (e.g. what type).
Quantitative = Quantity
Qualitative = Quality
Data collected about a numeric variable will always be quantitative and data collected about a categorical variable will always be qualitative. Therefore, you can identify the type of data, prior to collection, based on whether the variable is numeric or categorical.
Why are quantitative and qualitative data important?
Quantitative and qualitative data provide different outcomes, and are often used together to get a full picture of a population. For example, if data are collected on annual income (quantitative), occupation data (qualitative) could also be gathered to get more detail on the average annual income for each type of occupation.
Quantitative and qualitative data can be gathered from the same data unit depending on whether the variable of interest is numerical or categorical. For example:
|A person||“How many children do you have?”||4 children||“In which country were your children born?”||Timor-Leste|
|“How much do you earn?”||$60,000 p.a.||“What is your occupation?”||Photographer|
|“How many hours do you work?”||38 hours per week||“Do you work full-time or part-time?”||Full-time|
|A house||“How many square metres is the house?”||200 square metres||“In which city or town is the house located?”||Lospalos|
|A business||“How many workers are currently employed?”||264 employees||“What is the industry of the business?”||Retail|
|A farm||“How many milk cows are located on the farm?||36 cows||“What is the main activity of the farm?”||Dairy|
How can you use quantitative and qualitative data?
It is important to identify whether the data are quantitative or qualitative as this affects the statistics that can be produced.
The number of times an observation occurs (frequency) for a data item(variable) can be shown for both quantitative and qualitative data.