Strengths And Weaknesses Flashcards
A + D of lab experiments
A: controlled environment minimises extraneous variables.
Reliable
D: Low ecological validity because may not reflect how people behave in everyday life so can’t be generalised to everyday scenario.
Participants might change the way they behave. (Demand characteristics).
More effort.
A+D field experiments
A: true to everyday life and high in ecological validity - more likely to act normal.
Less effort.
D: not controlled and lots of extraneous variables.
Reducing liability because it’s not standardised and replicable.
A+D Quasi experiments
A: high in ecological validity because they’re not manipulating the IV.
Helps us study variables we cannot manipulate.
D: difficult to conduct.
Can’t control some participant variables that may influence the results.
A+D repeated measures design.
A: no participant variables (personality and persons life won’t effect results).
Only need to get half the people so it’s easier to collect sample.
D: the participants could change their behaviour if they work out what the study is about (demand characteristics).
Order effects- may get better or worse next time they do it as they’ve had practice.
A+D independent measures design
A: no demand characteristics (because the participant won’t know what the opposite participant is doing so won’t be able to work out the aim of the procedure and change their behaviour.)
No order effect- no practice.
D: Extraneous variables - participant variables.
Double people needed- effort.
A+D matched participants design
A: reducing participant variables.
No order effects or demand characteristics.
D: Can’t get rid of participant variables completely.
More effort.
A+D self selecting sample
A: participants will be cooperative because they want to do it + more likely to continue for the entire study.
Easy to obtain.
D: Demand characteristics.
Unrepresentative sample- all part of one group e.g. unemployed or keen on psychology.
Expensive if given money incentive.
Could mean a small sample size.
A+D opportunity sampling
A: easy to obtain at the time of study.
Act naturally - no demand characteristics.
D: unrepresentative sample.
Researcher bias.
A+D random sampling.
A: everyone has equal chance of being selected.
Representative of target population.
D: Everyone has equal chance of being selected -outliers.
Sometimes hard to ensure all have equal chance.
Selected people may not be willing to take part.
A+D snowball sampling
A: Easy to obtain (especially if difficult target population).
D: participant variables.
Not able to generalise sample- family and friends often have similar characteristics.
How can participant variables be controlled?
Have same people in each condition - repeated measures design or extremely similar groups of people- matched participants design.
Use random sampling so participant variables are more likely to be evenly distributed.
How can order effects (situational variables)be controlled?
Having different people in each condition - independent measure design or matched participants design.
If repeated measures design used, this should be counter-balanced (participants split into 2 groups; group 1 doing condition A and group 2 doing condition B.)
How can environmental factors (situational variables) be more controlled?
Impose controls on the experiment to ensure there are as few differences as possible between the two conditions e.g. same room, same temperature levels, same colour walls, same lighting.
How can demand characteristics (situational variables) be more controlled?
Don’t tell participants the aim of the investigation (single blind procedure).
Strengths and weaknesses of the range and how is it calculated.
Biggest - smallest. A: Easy to calculate. Shows the spread between the min and max values. D: Doesn’t show if the spread is even. Can be skewed by outliers.
