Experimental Method Flashcards
Define experiment
- the prime method of inquiry in science
- investigation in which a HYPOTHESIS is tested
- the IV is manipulated
- the DV is measured
- any EVs are controlled
key features of an experiment are?
- control over variables
- careful measurement
- establishing cause & effect relationships
IV
the cause
is manipulated
DV
the effect
is measured
Advantage of an Experiment is?
they should be OBJECTIVE
the views and opinions of the researcher should NOT affect the results
:)= makes data MORE VALID, LESS BIASED
Define Lab Experiment
- conducted under highly controlled conditions
- makes accurate measurements possible
- NOT necessarily in a lab
- participants are randomly allocated to each IV group
What does the researcher decide in a LE?
- where the experiment will take place
- @ what time
- w/ which participants
- in what circumstances
- using a standardised procedure
Pros of LEs
- easier to replicate an LE= because a standardised procedure is used
- LEs allow for precise control of EVs & IVs= allows a C&E relationship to be est
Cons of LEs
- the artificiality of the setting may produce unnatural behaviour that does NOT reflect real life= LOW ECOLOGICAL VALIDITY- means impossible to generalise results
- demand characteristics/ experimenter effects may BIAS the results and become CVs
Examples of LEs
- Milgram Obedience
- Loftus & Palmer= car crash study
Define Field Experiment
- are done in the everyday environment of the participants
- the experimenter STILL manipulates the IV but in a real life setting- thus can NOT control EVs
Pros of FEs
- behaviour in an F= MORE LIKELY to reflect real life because of its natural setting= HIGHER ECO VALIDITY
- there’s LESS LIKELIHOOD of DCs affecting the results= as the participants may NOT know that they’re being studied (COVERT)
Cons of FEs
- less control over EVs that might BIAS the results- makes it hard for REPLICATION
Example of FE
Hofling (1966) hospital experiment
Define Natural Experiment
- conducted in the banal environment of the participants, but here the experimenter has NO control over the IV as it occurs NATURALLY in real life
Example of NE
Hodge’s & Tizard’s attachment research (1989)
Hodge & Tizard (1989)
- compared the LT development of kids who’d been adopted, fostered or returned to their moms
- w/ a CG of kids who’d never parted from their families
Pros of NEs
- behaviour in a NE= natural- HIGH ECO VALIDITY- more likely to reflect real life
- LESS likelihood of DCs affecting the results= participants may NOT know they’re being watched
- can be used in situations where it’d be ETHICALLY UNREASONABLE to manipulate the IV= ex: researching stress
Cons of NEs
- may be more cher & time consuming than LEs
- NO control over EVs that might BIAS the results- makes it hard for REPLICATION
