Aims, Hypotheses, Variables

What comes before an aim during an experiment?

A research question they are trying to answer

What is an aim?

A statement about what the researcher is investigating, usually quite broad

What should every aim begin with?

‘To examine the effect of…’

What do variables help to identify in a study?

Whether the study is following an experimental methodology or not

What are the types of variables?

Independent and dependent variables

What is an independent variable?

The variable that the researcher manipulates and which is assumed to have a direct effect on the dependent variable

What is a dependent variable?

The variable that the researcher measures which is affected by the changes in the independent variable

What is meant by an experimental method?

A method that tests cause and effect, if the experimenter manipulates something it will cause a predicted effect

What is a quasi-experiment?

Not a true experiment, studies used to estimate the impact on a target population without random assignment e.g. experiments comparing males and females as not all characteristics are randomised

What is meant by operationalising?

Identifying exactly how the IV and DV will be measured

Why is operationalising variables important?

It provides reliability as the research can be replicated to achieve consistent results

Why should the dependent variable be very specific?

It makes it better as its easier to repeat the experiment e.g. ad

What is a hypothesis?

Statement about the predictions of the results from an experiment

What are the general rules when formulating hypotheses?

Written in the future tense

Include both conditions of the independent variable

Include the dependent variable

What are the types of hypotheses?

Null

Directional/One-tailed

Non-directional/Two-tailed

What is a null hypothesis?

Predicts no difference will be found in the results between the conditions

What do null hypotheses often start with?

‘There will be no difference…’

What is a directional hypothesis?

States the specific direction the researcher expects the difference to move in

What key words to directional hypotheses often start with?

Higher, lower, more, less, etc

What is a non-directional hypothesis?

State that a difference will be found between the conditions of the independent variable but does not state the direction of difference

What do non-directional hypotheses usually start with?

‘There will be a difference’

Why must all research have a directional/non-directional hypothesis and a null hypothesis?

Because they must reject one hypothesis and accept the other once research is conducted

What is an examples of an operationalised non-directional hypothesis?

Drinking more than 3 units of alcohol will increase reaction times than drinking less then 3 units of alcohol

What is an example of an operationalised non-directional hypothesis?

There will be a difference in the number of goals saved by a goal keeper between a football match and a training session

What are extraneous variables?

Variables other than the IV that MAY have an effect on the DV if it is not controlled

Where can extraneous variables come from?

Participant - age, intelligence

Surroundings - noise, temperature

Experimenter - personality, appearance

What are confounding variables?

Any variable other then the IV that has not been controlled and has affected the DV so we cannot be sure the true reason for changes to the DV

What are demand characteristics?

When a participant tries to figure out the aim of the experiment so alters their behaviour to either do what they think is being asked or deliberately do the opposite

What are investigator effects?

Conscious or unconscious behaviour by the experimenter that effects the DV

What are examples of investigator effects?

Design of the study

Selection of participants

Interaction with participants

What are ways to minimise extraneous/confounding variables?

Randomisation

Standardisation

What is randomisation?

The use of chance to control effects of bias

What is standardisation?

Using identical procedures for all participants

What are examples of standardisation?

Same environment, instructions, set script, room temperature, time of day, etc