Terms
What is Psychology?
Psychology is the scientific study of human behaviour and mental states.
What is the aim?
The aim is the purpose of the experiment.
What is an extraneous variable?
A variable that is not the IV, but may cause an unwanted effect on the DV
Convenience sampling
Involves sampling participants who are readily available and willing to participate in research, without making any effort to make the sample representative
Eg. volunteers
Any environmental factor that MAY affect the DV
What is the scientific method?
Used to obtain knowledge that involves hypothesis formulation, testing, and retesting through processes of experimentation, observation, measurement, and recording.
It is centred around generating an informed hypothesis (a prediction) and then testing it to generate evidence that either supports or refutes it.
What is the difference between population and sample?
Population: is the entire group of people the researcher is interested in. It refers to a group of people with similar characteristics.
Sample: is a smaller group of participants selected from the population. It should be representative of the population.
What is a confounding variable?
A variable that has directly affected the DV
Random sampling
A common method of sampling which aims to ensure every member of the population has an equal chance of being selected in the sample (random)
What are demand characteristics?
Cues in an experiment that may signal the intention of the study
What are order effects?
The tendency of the order in which participants complete experimental conditions to have an effect on their behaviour
What is the research hypothesis?
A hypothesis is an educated guess about what the results will be, usually based on knowledge of previous research findings.
What's an example of a participant-related variable in an experiment testing food consumption on mental fatigue?
Age, intelligence
Stratified sampling
Stratified sampling involves dividing the population to be sampled into distinct subgroups, then selecting a separate sample from each group in the same proportions as they occur in the target population.
What is the benefit of counterbalancing?
What are placebo effects?
When participants respond to inactive substance or treatment as a result of their expectations
What are the 4 things a research hypothesis needs?
Independent Variable
Population
A specific prediction
Dependent Variable
What is a controlled variable?
Controlled variables are variables other than the IV that a researcher holds constant (controls) in an investigation, to ensure that changes in the DV are solely due to changes in the IV.
Strengths of random sampling?
Easy to gather a large number of participants
Large sample sizes will be more likely to be representative
What is the benefit of single-blind procedure
Reduces participants expectations
Experimenter effect/bias
When the expectations of the researcher affect the results
What's the difference between IV and DV?
A variable that is manipulated is known as the independent variable (IV)
The variable that is measured and may change based on what happens to the IV is known as the dependant variable (DV)
How can we operationalise the following IV and DV:
Studying
Test scores
(time spent) studying
test scores (above certain number)
Limitations of stratified sampling?
Access to all members of population
Time consuming and expensive
Cannot force people to participate
What are non-standardised instructions and procedures?
When directions and procedures differ across participants or experimental conditions