research methods: lab/field/natural experiment

Question 1

laboratory experiments

Answer 1

• takes place in lab or controlled setting
• seen as more scientific and objective method
• one variable (iv) is manipulated and other variables kept constant and controlled so effects can be seen on what is being measured (dv)
• have experimental and control conditions - experimental group does something and control group does not. control group provides a baseline measure e.g. what the dv would be without any manipulation. results from experimental group are compared to baseline measure
• to be true experiment ppts should be randomly assigned to experimental or controlled conditions
• participant and situational variables are controlled e.g. using same room at same time of day (situational variables** and making sure as far as possible that ppts were not hungry in one of conditions and not the other and so on (participant variable)
• aim of lab experiment is to find cause and effect conclusion so that scientific knowledge can be built

Question 2

field experiments

Answer 2

• carried out in field - natural setting e.g. school for teachers or pupils, hospital for doctors, nurses or patients or prison for prisoners and guards
• apart from natural setting, field experiments have same features as lab experiments including manipulated iv and measured dv, controls (e.g. standardised procedure/instructions) and aiming for cause and effect conclusions

Question 3

strengths: laboratory

Answer 3

• easier to replicate a lab experiment. this is because a standardised procedure is used
• allow for precise control of extraneous and independent variables. this allows a cause and effect relationship to be established

Question 4

weaknesses: laboratory

Answer 4

• artificiality of setting may produce unnatural behaviour that does not reflect real life e.g. ecological validity. this means it would not be possible to generalise the findings to a real-life setting
• demand characteristics or experimenter effects may bias the results and become confounding variables

Question 5

strengths: field

Answer 5

• behaviour in a field experiment is more likely to reflect real life because of its natural setting e.g. higher ecological validity than lab experiment
• less likelihood of demand characteristics affecting results, as ppts may not know they are being studied. this occurs when the study is covert

Question 6

weaknesses: field

Answer 6

• less control over extraneous variables that might bias results. this makes it difficult for another researcher to replicate the study in the same way