Experimental method

Question 1

What types of experiment are there

Answer 1

1) lab experiment
2) field experiment
3) natural experiment
4) quasi experiment

Question 2

what is a lab experiment

Answer 2

an experiment conducted in a special environments where variables can be carefully controlled and participants are aware they are taking part in the experiment

The researcher manipulates the independent variable

Question 3

Evaluate a lab experiment

Answer 3

+have high internal validity as extraneous variables are controlled increasing confidence that observed changes are due to the IV

• participants are aware their behaviors are being studied affecting behaviors
• low in mundane realism, IV or DV may not be operationalized in a way that reflects real-life experiences

Question 4

what is a field experiment

Answer 4

a type of experiment conducted in a natural setting in which the investigator still controls the independent variables
participants are not usually aware they are being observed

Question 5

evaluate a field experiment

Answer 5

+ participants not usually aware they are being watched decreasing demand characteristics increasing ecological validity of the experiment

• it’s harder to control extraneous variables
• ethical issues - if PPS don’t know they are being observed they are unable to give informed consent and it is hard to debrief them

Question 6

what is a natural experiment

Answer 6

a type of experiment in which the researcher has not manipulated the IV directly
the change in IV would occur naturally, all the researcher does is record the effect of the natural change in the IV on the DV

Question 7

Evaluate a natural experiment

Answer 7

• lack of control of extraneous varibales= unsure if the effect of the DV was due to changes in the IV, this means conclusions about cause or effect can only be tentative
  + the studies of the samples in a natural experiment may have unique characteristics, change arent brought about by researcher allowing investigation of unethical situations

Question 8

what are the types of experimental designs

Answer 8

1) Repeated measures
2) independent groups
3) matched pairs

Question 9

what is independent groups design

Answer 9

participants are allocated to two or more groups of the IV- PPS partake in separate experimental conditions

Question 10

evaluate independent group designs

Answer 10

• participant variables cant be controlled, such as different abilities or characteristics which act as confounding variables
• large amount of participants needed in comparison to repeated measures in order to end up with the same amount of data

Question 11

what methods can be done to deal with limitations of independent group design

Answer 11

Random allocation= allocate pps to random conditions, allows participants variables to be evenly distributed across experimental conditions

Question 12

what is repeated measures

Answer 12

each participant takes part in all the experimental condtions

Question 13

evaluate repeated measures

Answer 13

• order effects= the order of conditions may affect performance as pps may do better in the second condition due to practice effect
• when doing the second test pps may guess what the purpose is and change behaviours= demand characteristics

Question 14

how can limitations be overcome for repeated measures

Answer 14

counterbalancing to overcome order effect

a cover story to avoid pps guessing true aims of the study reducing demand characteristics

Question 15

what is matched pairs design

Answer 15

pairs of pps are matched on key characteristics such as age or gender, then assigned to separate experimental condtions

Question 16

evaluate matched pairs design

Answer 16

• time consuming= it is hard to match pps on key variables= needs a large sample
• not possible to control pps variables because you can only match on variables known to be relevant