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Lesson objectives What is a target population? Identify and describe different sampling methods Replicate sampling methods using Discuss strengths & weaknesses of different sampling techniques Recap on key terminology Upcoming assessment briefing

Target Populations ‘general statements’ Psychologists are interested in making ‘general statements’ about behaviour. sample generalise We can’t test every single person in the world, so psychologists take a sample of people and try and generalise their findings to the population. A psychologist may be interested in a particular group of people, e.g. Drinking behaviour in year olds living in the UK. TARGET POPULATION This would mean that all years in the UK would be the TARGET POPULATION.

Target Populations A sample can be collected by psychologists in a number of different ways. Obviously it will depend on the type of research being conducted. You need to be able to consider which of these sampling methods are the best to use. Obviously it will depend on the type of research being conducted. Random Sampling Opportunity Sampling Volunteer Sampling Stratified Sampling

Skittles Sampling Record the number of different coloured Smarties that you collect for each type of sampling.

Random sampling Every member of the target population has an equal chance of being selected. Every Skittles has an equal chance of being selected How do you think we could select 5 Skittles from our packet at random?

Systematic Sampling A systematic sample involves the researcher choosing the nth person on the list. E.g. You may chose every 5 th person from your Psychology class register Show me a systematic sample of every 3 rd Skittle in your packet.

Opportunity Sampling An opportunity sample uses participants who are available at the time of the research being conducted. E.g. You may chose the first students that pass you in the corridor Without much thought tip your Skittles onto the table and select the 6 Skittles that are nearest to you

Volunteer Sampling GreenSkittlesWanted How many green skittles do you have? We’ll presume they all volunteer to take part in our study.

Extension Tasks Scenario 1: A psychologist wants to conduct research into healthy eating habits in year old students through questionnaires. Where should she get her sample from? What type of sampling methods would be best to use and why?

Extension Tasks Scenario 2: A psychologist wants to investigate whether violence on TV can influence young children to be aggressive. Where should he get his sample from? What type of sampling method would be best to use and why?

Extension Tasks Scenario 3: A psychologist is researching whether Psychology students have better memories than Economics Students. Where should she get her sample from? What type of sampling methods would be best to use and why?

Extension Tasks Yes/No game Students to stick given experiment key concept to their foreheads and in groups of 5 have to ask questions to the rest of their group to decide what concept they are. Questions can only be answered using ‘yes’ or ‘no’

You say we pay