sampling techniques

• What is a random sample in research?

  Everybody in the target population has an equal chance of being selected.
• Give an example of a random sampling method.


  Names drawn out of a hat or using a random number generator.
• What is an opportunity sample?


  It uses participants who are available at the time.
• Provide an example of an opportunity sample.


  Using people in the common room to take part.
• What is a stratified sample?

  It identifies subgroups in proportion to the target population and then uses random sampling from those subgroups.
• How does a systematic sample work?

  It uses every Nth person in the target population.
• What is a volunteer sample?


  It advertises to the population and uses participants that come forward to take part.
• What does it mean for a sample to be representative?


  It reflects the characteristics of the people in the target population.
• What does generalisable mean in research?


  It refers to whether findings from the sample can be applied to the target population.
• What does bias refer to in sampling?

  It refers to whether your sample is completely fairly selected.
• What is random allocation in an experiment?


  It is the process of arranging participants into conditions of the experiment after selecting the sample.
• What are the steps in random allocation?

  1. Number all participants.
  2. Put the numbers in a hat.
  3. The first number pulled out goes to Condition A.
  4. The next number goes to Condition B.
  5. Repeat until all participants are allocated.
• What is a strength of random sampling?

  It is unbiased; all members of the target population have an equal chance of being selected.
• What is a weakness of random sampling?

  It requires a list of everyone in the population and takes time to contact those selected.
• What is a strength of opportunity sampling?

  It is the easiest method and reduces costs and time taken to find participants.
• What is a weakness of opportunity sampling?

  It can produce bias as it draws from a small part of the population.
• What is a strength of stratified sampling?

  It is the most representative method as the sample is proportionate to subgroups and random.
• What is a weakness of stratified sampling?

  It is very time-consuming to identify subgroups and randomly select participants.
• What is a strength of systematic sampling?

  It is unbiased, as participants are selected using an objective system.
• What is a weakness of systematic sampling?

  It is not truly random unless you start with a random method for selecting the first participants.
• What is a strength of volunteer sampling?


  It can provide a wide variety of people, making the sample more representative.
• What is a weakness of volunteer sampling?

  It may be biased towards people who are motivated or confident, resulting in volunteer bias.