Pages in this set

Page 1

Preview of page 1
OCR AS Psychology Investigations revision notes

A single number that describes the degree of relationship between two variables, particularly where it would
be difficult or unethical to experiment.

Naturalistic form of research. No manipulation of IVs or EVs.

Because it's naturalistic, can NEVER establish cause and effect

Correlational hypothesis:…

Page 2

Preview of page 2
Invalid data may be provided. This may be due to embarrassment (social desirability bias) or the
may be deceiving themselves (e.g. alcoholics)
If the question is leading (the researcher suggests an answer in the question) the data will be invalid

Structured all questions are preset
Unstructured there are no…

Page 3

Preview of page 3

Limits the answers participants can choose from, so it is possible the answer they want to give is not
Scales can be interpreted different, practically if each value does not have a clear meaning. (e.g. the
score 3 may mean different things to different participants)

In experiments…

Page 4

Preview of page 4
Individual differences. It may be the participants difference that create the difference in scores, not
the IVs (so you cant conclude the IV caused the DV)

Measures of central tendency
Mean can be distorted by extraneous scores
Mode better if there are two or more `bumps' in the graph as…

Page 5

Preview of page 5
Structured/ unstructured observations
Structured The researcher designs a coding scheme* to record behaviour.
Unstructured the researcher records all the behaviour they see.

*Coding schemes
A coding scheme is a list of behaviours which the observer ticks when they see that behaviour happen.

Structured observations strengths/weaknesses
Simple to carry out…

Page 6

Preview of page 6

Interrater (or inter observer) reliability
Reliability= consistency!
IN observations, reliability always referred to if two observers scored independently, would they get the
same results.
Most observations have 2 observers, if not the behaviour observed could just be the opinion of the
If the 2 observers get same/ similar results,…

Page 7

Preview of page 7
Stratified sampling classifying the target population into categories and then choosing a sample which
includes participants from all the categories.

Strengths and weaknesses
Strengths Weaknesses
Opportunity Quickest and easy to conduct Sample can be biased, as researcher will
choose from their social/ cultural group.
People chosen may refuse, giving an…

Page 8

Preview of page 8
Check your measuring system against something else which measures the same thing
Improving reliability will improve validity!


Rees *Redacted*


This is some awesome, and very condensed notes :)

I'm doing a re-take, and I find these very useful.

Similar Psychology resources:

See all Psychology resources »