types of experiment

Question 1

describe lab experiments

Answer 1

take place in a controlled environment.
researcher manipulates IV. records effect on DV. strict control of extraneous variables

Question 2

describe field experiments

Answer 2

takes place in a natural setting. researcher still manipulates the IV and measures the DV and attempts to control extraneous variables

Question 3

describe natural experiments

Answer 3

not ‘true’ experiments. the change in the IV is not brought about by the researcher but would have happened even if the research had not been there

Question 4

describe quasi experiments

Answer 4

IV based on an existing difference between people. It exists and is not manipulated (not a true experiment)

Question 5

strengths and weaknesses of a lab experiment

Answer 5

STRENGTHS:
strict control over extraneous variables- cause and effect relationship can be established
easy to replicate

WEAKNESSES:
lack ecological validity as they are in an unnatural environment
demand characteristics and experimenter effects can threaten validity

Question 6

strengths and weaknesses of field experiments

Answer 6

STRENGTHS:
high ecological validity as it is in a natural setting- can be generalised to other settings and the population
low or eliminated demand characteristics

WEAKNESSES:
harder to replicate
recording results can be problematic as it may not be possible to use the necessary equipment in a natural environment
not always possible to control extraneous variables

Question 7

strengths and weaknesses of natural experiments

Answer 7

STRENGTHS:
high in external validity as they are extremely generalisable
allow for experiments that may not otherwise be possible due to practical or ethical reasons

WEAKNESSES:
happen by chance- cannot be replicated, reduces research opportunities
cannot establish a cause and effect relationship

Question 8

strengths and weaknesses of quasi experiments

Answer 8

STRENGTHS:
allow comparisons to be made between two groups of people
can be carried out in lab conditions- control over extraneous variables

WEAKNESSES:
cannot establish a cause and effect relationship as the IV is not directly manipulated
could lack internal validity (demand characteristics) and external validity (not real life conditions)

Question 9

explain what is meant by an aim

Answer 9

a general statement which describes the purpose of the investigation

Question 10

explain what is meant by a hypothesis

Answer 10

a precise and testable statement about the relationship between two variables