Internal validity concerns what goes on inside a study. It is concerned with things such as:
- Whether the IV produced the change in DV (or did something else effect the DV?)
- Whether the researcher tested what he/she intended to test.
- Whether the study possessed (or lacked) mundane realism
To get high internal validity you must design the research carefully, controlling extranious variables and ect...
External validity is affected by internal validity - it concerns the ability to generalise the results of a study to:
- Different places or settings (Ecological validity)
- Different people or populations (Population validity)
- Different times (Historical validity)
Informed concent - Participants gave the right to be given comprehensive information concerning thr nature and purpose of the research and their role in it, in order that they can make an informed decision about whether to participate
Confidentiality - A participants right to have personal information protected
Deception - Where a participant is not told the aims of a study (e.g. what participation will involve) and thus cannot give truly informed concent
Privacy - A person's right to control the flow of information about themselves.
Protection from harm - During a research study, participants should not experience negative physical or psychological effects
Right to withdraw - Participants should have the right to withdraw from participating in a study if they are uncomfortable in any way, and should also have the right to refuse permission of the researcher to use any data they produced
Experiments and hypotheses
A hypothesis states what you believe to be true. It is a precise and testible statement of the relationship between two variables .
Directional hypothesis -states the expected direction of your results (i.e. People who do homework with the TV on, produce better results than those that do homework with the TV on)
Non-directional - Predicts that there will be a difference between two conditions or two groups of participants. (i.e. People who do homework without the TV on, produce different results than thos who do homework with the TV on)
Laboratory and field experiments
Laboratory experiment - An experiment conducted in a special environment where variables can be carefully controlled. Participants are aware they are taking part in an experiment, though they may not know the true aims of the study
Field experiment - An experiment conducted in more natural environment. As with an laboratory experiment the IV is still deliberatly manipulated by the researcher. Participants are often not aware they are participating in an experiment.
Observational methods and techniques
In an observational study participants are observed engaging in whatever behaviour is being studied.
- In a naturalistic observation behaviour is studied in a natural situation where everything has been left as it is normally
- In a controlled observation some variables are controlled by the researcher, reducing the 'naturalness' of the behaviour being studied. Participants are likely to know they are being studied and the study may be conducted in the lab
Structured observations - The researcher uses various systems to organise observations.
- Behavioural categories - How to record the behavour you are interested in
- Sampling procedures - Who you onbserving and when
Unstructured observations - The researched records all relevent behaviour but has no system. The behaviour studied is largely unpredictable.
A questionaire is a set of questions. it is designed to collect information about a topic or topics
- You can collect the same information from a large number of people relatively easily
- You can access what people think - observations and experiments rely on guessing what people think and feel on the basis of how they behave
A structured interveiw has pre-detirmined questions
An unstructured interveiw has less stucture! New questions are developed as you go along.
A semi-structured approach combines both stuctured and unstructured questions.