Discrete Data (Mathematics Glossary)
What Is Discrete Data?Discrete data can only take certain values. It can (often) be counted.
Discrete data is a type of quantitative data. It is described in numbers.
Dictionary DefinitionThe Oxford English Dictionary defines discrete as "quantity composed of distinct units, as number, in contrast to continuous quantity or magnitude."
Real Examples of Discrete Data
- A teacher collects the test scores of their class.
The test scores of the pupils are discrete data. Pupils can only get a whole number of marks. 5 marks or 8 marks make sense, but 51/8 marks does not make sense.
- Different shapes have different numbers of sides.
The number of sides are discrete data. You can only have a whole number of sides. It doesn't make sense to have ½ a side.
More Real Examples of Discrete Data - Not Just Whole NumbersFrom the examples above, we see that when we count a whole number of items, we get discrete data.
However, values do not need to be whole numbers to be discrete, as the following examples demonstrate.
- A cake shop sells slices of cake. Each slice is an 1/8th of a cake. Customers can only buy multiples of 1/8ths of a cake.
- Shoes come in different sizes. Shoe sizes usually come in whole numbers, but occasionally come in ½ sizes.
Here's a second test on discrete data.
Here's a third test on discrete data.
Other Types of DataThe types of data are given below:
Discrete and Continuous DataDiscrete date is a type of quantitative data.
The other type of quantitative data is continuous data.
Whereas discrete data can only take certain values, continuous data can take any value (within a range).
Discrete data is restricted to certain values (1, 2, 3 etc) and can't take any values in between. Continuous data can take values in between (1, 1.1, 1.25 etc).
Quantitative and Qualitative DataDiscrete date is a type of quantitative data, which means it is described in numbers.
There is also qualitative data, which is described in words.