4.2.3 Research Methods (a) Flashcards
AO1
Define experimental method.
◦ The experimental method concerns the manipulation of an independent variable (IV) to have an effect on the dependent variable (DV), which is measured and stated in results.
AO1
Outline the aim of laboratory experiments.
Reference a research study conducted using this method.
◦ The aim of laboratory experiments is to control all relevant variables except for one key variable which is altered to see what the effect is.
◦ The variable altered is the independent variable.
Example: Milgram’s Study (Artificial Setting)
AO3
Outline the strengths of laboratory experiments.
◦ High Degree of Control: Experimenters control all variables the IV has been precisely replicated, leading to greater accuracy.
◦ Replication: Researchers can repeat experiments and check results. (increases reliability)
◦ Causal Relationships: Ideally, it’s possible to establish whether one variable actually causes change in another.
AO3
Outline the limitations of laboratory experiments.
◦ Experimenter’s Bias: This bias can affect results and participants may be influenced by these expectations. (reduces internal validity)
◦ Low Ecological Validity: High degree of control makes the situation artificial, and unlike real life. (reduces external validity)
AO3
Outline: Strengths of field experiments.
◦ Naturalistic: So more natural behaviours, hence greater ecological validity.
◦ Controlled IV: Can still establish a causal relationship (through manipulation of the key variable and measuring its effect), although it’s very difficult to do in a field experiment.
◦ Demand Characteristics: These can be avoided if participants do not know if they’re in a study. (covert study)
AO3
Outline: Limitations of field experiments.
◦ Ethical Considerations: Invasion of privacy (psychological harm (e.g. distress)) and likely to have been no informed consent.
◦ Loss of Control: Loss of control over extraneous variables, hence precise replication not possible.
AO1
Outline laboratory experiments and
describe how they can be carried out.
◦ An experiment that takes place in a special environment whereby different variables can be carefully controlled.
This can be done using:
* Standardised Instructions: Instructions given to each participant are identical to help prevent experimenter bias.
* Standardised Procedures: In every step of the research, the participants are treated in the same way and so all have the same experience.
Experiments often have a control group (a group that is treated normally and gives researchers a measure of how people behave when they are not exposed to the experimental treatment), and always have at least one experimental group (the group that received the experimental treatment).
AO1
Outline: quasi-experiments.
◦ An experiment where the IV has not been determined by the researcher, instead it naturally exists.
e.g. gender difference studies
AO1
Outline the strengths of quasi-experiments.
◦ Controlled Conditions: Hence replicable; likely to have high internal validity.
◦ Ecological Validity: Research is often less artificial than laboratory studies, so more likely to be able to generalise results to real life.
◦ Ethics: It is possible to study variables that would be unethical to manipulate.
Suggest how the replicability of a research study can be improved.
- The replicability of a study can be improved through the use of standardization.
- ◦ Standardised Instructions: Instructions given to each participant are identical to help prevent experimenter bias.
- ◦ Standardised Procedures: In every step of the research, the participants are treated in the same way and so all have the same experience.
- This allows for the elimination of non-standardised instructions as being possible extraneous variables.
Describe how causal relationships can be accurately established within experiments.
◦ Precise control of extraneous and independent variables.
This allows a cause and effect relationship to be established as it is possible to establish whether one variable actually causes change in another.
Outline the limitations of quasi-experiments.
- Participant Allocation: Cannot randomly allocate participants to each condition, and so confounding variables may affect results.
- Causal Relationships: Difficult to establish cause and effect because the independent variable isn’t being directly manipulated.
- Replication: Generally difficult to replicate, and therefore can lack internal and external reliability.
Outline: Natural Experiments.
- An experiment in which the IV is not brought about by the researcher hence would have happened even if the researcher had not been there e.g. if studying reactions to earthquakes.
Outline the limitations of natural experiments.
- Replicability: Natural occuring events may be rare, meaning these experiments are not likely to be replicable, hence it is difficult to generalise findings.
- Very Difficult to Randomise: Difficult to randomise participants into groups, therefere confounding and extraneous variables become a problem.
- Expensive and Time-Consuming: They may be more expensive and time-consuming than lab experiments.
- Ethical Considerations: Deception often used, making informed consent difficult. Confidentiality may be compromised if the community is identifiable.
Outline the strengths of natural experiments.
- Theory Development: Provides opportunities for research that would have otherwise been impossible due to practical or ethical reasons.
- High External Validity: Involves real-life contexts (greater ecological validity + generalisability).
- Demand Characteristics: Participants may not know they are in a study, so their behaviour is likely to be more natural.
