Quota Sampling, Opportunity (convenience) Sampling

Divide the sample into groups that are proportionally sized to the entire population , Assess each person and allocate them into a quota, When each quota is full (e.g. 3 black people), no more people that fit into that group can be selected

Taking information from the people who are first available (e.g. questioning the first 20 people you see at a bus stop)

Allows a small sample to be representative of the whole population, No sampling frame required, Quick, easy, and inexpensive, Can easily compare different groups in a population

Can introduce bias, Dividing into groups can be accurate if they aren't distinct enough, Can be expensive if a large group is studied, Non-responses aren't recorded

Easy to carry out, Inexpensive