Research methods

What is an independent variable?

The variable directly manipulated by the researcher to see the effects of such a change

What is a dependent variable?

The variable a researcher measures to see the effects of their changes to the independent variable

What is an experiment?

The method of research in which all variable (extraneous variables) other than the IV and the DV are controlled, this allows the researcher to identify cause and effect relationship between the IV and DV

What are extraneous variables?

Variables other than the IV and the DV which need to be controlled to make sure that the IV has definitely caused the DV

What is a situational variable?

An extraneous variable present in the environment of the study

What is a participant variable?

Extraneous variables specific to the participants of an investigation

What is a confounding variable?

Variables that haven’t been controlled and consequently affect results

What are standardised procedures?

Where the procedure of a study is the same across all conditions for all participants so they are all treated the same to make the study unbiased

What is counterbalancing?

Where half of the participant group experience condition A then condition B, while the other half experience condition B then A, to reduce order effects

What is randomisation?

When participants are randomly assigned to condition A or B as their first of second test condition, to reduce order effects and researcher bias

What is the double-blind technique?

When the aims of the study are withheld from both participants and researchers to reduce demand characteristics

What is the single blind technique?

When information about the study is kept from participants (deception) to reduce demand characteristics

What is random allocation?

If independent group design is used then participants should be randomly allocated to one of the 2 conditions to help reduce bias and prevent a certain type of person being in one condition (controls participant variables)

What is a null hypothesis?

A prediction that the results will fail to show any difference (or relationship) that is consistent or systematic e.g. There will be no difference…

What is an alternative hypothesis?

Isn’t the aim of a study, it is a statement which serves as a prediction, based on the theory being tested

What is a directional hypothesis?

A hypothesis that predicts the direction the results will go in

What is a non directional hypothesis?

A hypothesis that predicts a difference will be found, but doesn’t specify what the difference will be

What is the target population?

The group of people being investigated by the study

What is the sample?

A selection of the target population that is directly studied in an investigation

What is generalisability?

The extent to which the results of a study represent the whole population, not just the sample used

What is random sampling?

Once you have identified the target population you then select the sample that you need by giving everyone an equal chance of being picked

Give two strengths of random sampling

• No researcher bias as researcher doesn’t actively pick sample

• All have equal chance of being picked so should generate a representative sample

Give two weaknesses of random sampling

• Sample may not be representative

• Can be difficult to get the list of the whole target population

What is opportunity sampling?

This involves selecting the first people who happen to be present at the time of the study. Can be done with agreement or covertly

Give a strength of opportunity sampling?

• Quickest and cheapest way to get sample in comparison to other techniques

Give to weaknesses of opportunity sampling?

• Possible researcher bias as they actively pick the sample themselves so may not have a representative sample

• Difficult to replicate and therefore unreliable