Maths - Stats

Population

The whole set of items that are of interest

Census

Observes or measures every number of a population

Sample

A selection of observations taken from the population

Sampling Unit

An individual unit of a population

Sampling Frame

A numbered list of sampling units

Advantages of Sample

• Less time consuming

• Cheap

• Less data to process

Disadvantage of Sample

The data may not be representative of the population

Advantage of Census

It should give a completely accurate result

Disadvantages of Census

• Time consuming

• Expensive

• Large data set - hard to process

• Cannot be used when the testing process destroys the item

Simple Random Sampling