Experiments Flashcards
Name the three types of experiments
- laboratory experiments
- field experiments
- quasi (natural experiments)
Define a lab experiment
IV is manipulated by the researcher, experiment carried out in a laboratory or another contrived (artificial) setting (away from participants normal environment)
Define field experiments
IV is manipulated by the researcher, experiment carried out using the participants normal surroundings
Define quasi experiments
The IV is naturally occurring, not manipulated by the researcher
(E.g cloudy/sunny conditions, morning/afternoon)
What is an experimental design
Deciding how to allocate participants to the different conditions in the IV
Name the three types of experimental designs
- repeated measures design
- Independent measures design
- matched participants design
Define repeated measures design
Involves using the same people in each condition
Define independent measures design
This involves using different people in each condition
Define matched participants design
This involves using different people in each conditions but an attempt is make to make the participants have similar key characteristics (that might influence findings)
Name 3 positives of a repeated measures design
- participant variables (e.g individual differences) are reduced
- potentially fewer people needed, saves time
- uses fewer participants, more cost-effective
Name 2 negatives of repeated measures designs
- order effects can occur
• practice effect (participants better the second time round)
• fatigue effect (performance worse second time round because they are more tired
Name 3 advantages of using Independent measures design
- avoids order effects (practice + fatigue)
- stops participants from guessing the aim of the study (prevents demand characteristics)
- potentially less time-consuming than matched participants and repeated
Name 2 negatives of using independent measures design
- more people needed (time consuming to find)
- differences between participants in the group may affect results (eg extraneous variables such as participants variables)
Name two advantages of matched participants design
- reduces participant variables (have similar characteristics and abilities)
- avoids order effects (counterbalance not necessary)
Name three negatives of using matched participants design
- impossible to match people exactly
- very time consuming
- one participants drops out you lose the data of two
