Lab experiment- an experiment which is conducted under highly controlled conditions. It looks for a difference between conditions (the independent variable) and tries to show cause and effect.
Aim- the reason you are carrying out the research.
Independent Variable- what is being change or manipulated?
Dependent Variable- what is being measured?
Participants- the people who take part in psychological studies.
Target population- the group of people you want to be able to apply your findings to. Your sample has to be representative of this population in order to be able to generalize the results.
Representative sample- where the sample used matches closely to the rest of the target population.
Cause and effect- a relationship between actions or events such that one is the result of the other. (Only experiments can show cause and effect)
Extraneous variable- a variable which could affect the dependent variable that needs to be controlled.
Confounding variable- A variable which has a unintentional effect on the dependent variable that wasn't controlled and may be causing changes instead of (or combined with) the independent variable.
Difference between confounding and extraneous variables:
An extraneous variable is a variable which could affect the dependent variable so needs to be controlled. If it is allowed to interfere with the dependent variable then it becomes a confounding variable.
Replication- when a study is carried out again using different participants. This allows the study to be checked for reliability off results and also find out if the results will generalize to other participants or situations.
How can a variable be operationalise/measured? Operationalise is to state clearly how a variable is manipulated or measured. You can adapt existing measures (e.g. instead of a score time how long a task takes), or give a new way to measure (e.g. use a different task/test, or a self-report scale or observation). Must be fully replicable for maximum marks.
What is standardization? Standardization ensures that each participant undertakes the study under the same situation and using the same scoring method. This will improve both the reliability and the validity of the study.
Situational Variables- these are extraneous variables that may affect the results of the study instead of the independent variable. Any feature of the environment which could influence the participant’s behaviour and which are not consistent for both conditions.
Participant Variables- these are extraneous variables that may affect the results of the study instead of the independent variable. It is any individual difference such as a trait or skill that makes certain participants naturally better at a task than other people.
Experimenter Variables- these are extraneous variables that may affect the results of the study instead of the independent variable. Any trait or feature of the researcher or their instructions which means that every participant is not treated in the same way.
Negative Correlation- where as the values of one variable increases the values of the other varaible decreases, although not necessarily at the same rate.
Positive Correlation- where as the values of one variable inreases the values of the variable also increases, although not necessarily at the same rate.
Ecological Validity- how true to life the study is, is the participant behaving in a way the would behave if not being studied?
Face Validity- refers to the extent to which a measure appears on the surface to measure what is is supposed to measure.
Reliability- how consistent a study or measuring device is. It is consistent if the measurement can produce similat results if used again is similar circumstances.
Quantitative data- numerical data which is easy to compare and analyze because it can be easily organisedd in charts and comparisions mad between reliability. (high reliability)
Qualitative data- data that is rich in description and meaning because it allows a participant to choose how much information to give and can say what they feel. (high validity)
Demand Characteristics- any aspect of a study which has an influence on participants to do or answer what is expected of them. This often occurs due to participants being aware of being tested and reduces the validity of results. A common way to reduce demand characteristics is to hide the true aim of the study from participants until the end.
Participant observation- is a type of observational study where the observer is also a participant in the activity being studied.
Inter-rater reliability- in observational research is whether different observers are able to observe and rate (or code) the same behaviour the same way.
How do you ensure inter-rater reliability in your observation? Train observers beforehand in the use of the coding scheme, clarify what the behavioural categories being used refer to and conduct a pilot study to test for agreement amongst observers. Discuss results afterwards.
Nominal data- data in seperate categories such as eye colour.
Ordinal data- data that are ranked such as the order of runners that finished the marathon- first, second, third and so on.
Interval data- there is the same differance between each value. The most common example is temperature.
Ratio data- interval data with a natural zero point e.g time ia ratio since 0 time is meaningful.
Longitudinal- a study done over a long period of time.
Snap-shot- a study done over a short period of time.