1. AS Psychology Research Methods
Methodological Issues

2. Reliability
Reliability – refers to how much we can depend on any particular measurement, and how much we can repeat the same study and consistently get the same result time and time again.
External reliability – the ability to replicate the results. It’s typically assessed using the test-retest method or test the correlation between two scores.
Internal reliability – the consistency of a measure within a test. It’s typically assessed using the split-half method (comparing half the test with the other to check consistency).

3. Reliability (Cont’d)
Test-retest reliability – the same test is given to the same sample on two different occasions.
Inter-rater reliability – the degree to which different rates/observers give consistent estimates of the same object.
Inter-observer reliability – the consistency between two researchers watching the same event, producing the same records.
Demand characteristics – predicting the experiment’s aim and acting accordingly, which could hinder results. Acting out-of-character due to surrounding environment. Displaying social desirability bias.

4. Reliability (Cont’d)
Strengths – if reliable experimental studies are replicated exactly, we would expect to achieve very similar results. If a questionnaire is reliable, then it is consistent in its measurement.
Weaknesses – the task of making studies reliable is time consuming. Data must be handled carefully and be precise.

5. Validity
Validity – refers to whether or not a study is measuring what it is supposed to measure.
Ecological validity – the extent to which the findings can be generalized to outside the research setting. How true the study’s location is to real life.
Mundane realism – refers to how true the task that participants are required to do is to real life.
Generalizability – how widely findings apply to other settings and populations.

6. Validity (Cont’d)
Strengths of high ecological validity – if a study is located in real-life setting, participants are more likely to behave normally. There is less likely to be demand characteristics. If a study is based on real life, it's more likely that strong generalizations can be made.
Weaknesses of high ecological validity – it may be impossible, on a practical level, to create a real-life situation or make something happen naturally. If a study is conducted in a natural environment, the experimenter may not have obtained the participants' consent, so the study would be unethical.

7. Validity (Cont’d)
Face validity – a judgement about whether a test seems to be valid.
Content validity – asking an expert in the field to assess and see if the study is an accurate measure.
Construct validity – assess how close the study relates to underlying theoretical constructs.
Criterion validity – whether a test of a particular construct relates to other measures of it. There are two types: Concurrent validity – whether the test shows similar findings to another existing measure. Predictive validity – how well a test predicts future performance.

8. AS Psychology Research Methods
The Issues and Debates

9. Individual vs. Situational
An individual (or dispositional) explanation for an event will look to some feature or characteristic in the person themselves.
A situational explanation will look at the wider context: the social group, the environment or even other people influencing our behavior.

10. Cont’d
Strengths of individual vs. situational – if we can discover which behaviors are individually determined and which are situationally determined, such findings may be useful for society. The power of the situation can help prevent us from blaming people for their behavior.
Weaknesses of individual vs. situational – there may be a complex interaction between the two. By investigating the power of the situational factor, we might expose participants to distressing or harmful situations. There are ethical problems.

11. Nature vs. Nurture
Nature here refers to the part of us that is inherited and genetic.
Nurture refers to all influences after our birth such as experience and societal norms/customs.

12. Cont’d
Strengths of nature vs. nurture – the distinction can help us identify which behaviors are inherited or learned, or allow us to consider the relative contributions of inheritance and learning. It can be valuable to discover that some behaviors are due to nature and not to poor upbringing by parents.
Weaknesses of nature vs. nurture – it's too simplistic, as the two often combine in complex ways to influence behavior. Discovering that a particular behavior is inherited might lead to the assumption that much more behavior is inherited, while failing to consider the effects of the environment. This could encourage eugenics.

13. Ethnocentrism
Ethnocentrism refers to a focus on a racial, cultural, or religious group, usually that of the psychologist conducting the research.
Strengths – allows us to discover that not all cultures are the same; to discover the diversity of behavior and experience that people all over the world have. Might allow us to discover the causes of prejudice; to realize that our values aren't the only ones possible. It educates us not to make value judgements.
Weaknesses – the sample in a study may be very small or representative of just one culture, and so findings cannot be generalized to all countries/cultures. Many cultures have different philosophies and so cannot be compared.

14. Usefulness
Usefulness refers to the study’s ability to provide us with a practical outcome which we can apply in the real world. Is there an application to the findings?
Strengths – it can be of benefit to society. It can improve the world in which we live in. It enhances the value and status of psychology as a subject.
Weaknesses – a study must be ethical, however, a study may need to be unethical in order to be truly useful. A study should use a representative sample and be generalizable. Useful research should apply worldwide so there is no ethnocentrism.