experiments

Question 1

what are the purposes of experiments?

Answer 1

they involve the manipulation of an independent variable to see its effect on the dependent variable

Question 2

what are the three types of experiments?

Answer 2

• laboratory
• field
• quasi

Question 3

what are laboratory experiments?

Answer 3

an experiment in an controlled environment, all other variables (extraneous variables) are controlled an kept at a constant

Question 4

what are positives of laboratory experiments?

Answer 4

• high control
• reliable
• replicable
• standardized procedures
• control EV’s
  = increases internal validity

Question 5

what ae negatives of laboratory experiments?

Answer 5

• decreases ecological validity
  = artificial environments
  = demand characteristics

Question 6

what are field experiments?

Answer 6

the experiment takes place in a natural environment e.g a participant’s home

Question 7

what are positives of field experiments?

Answer 7

• increases ecological validity
  = natural environments
  = low in demand characteristics

Question 8

what are negatives of field experiments?

Answer 8

• low control
  = decreases reliability
• EV’s may affect behavior
• lack of consent

Question 9

what are quasi experiments?

Answer 9

an experiment where the ‘IV’ is naturally occurring and not manipulated by the experimenter e.g hair colour or eye colour

Question 10

what are some positives of quasi experiments?

Answer 10

• you are able to investigate participants that would otherwise not be able to be investigated as i would be impossible or unethical

Question 11

what are some negatives of quasi experiments?

Answer 11

• it may be difficult o gather participants sometimes

Question 12

which is the ‘cause’ IV or DV?

Answer 12

IV

Question 13

which is the ‘effect’ IV or DV?

Answer 13

DV

Question 14

what are extraneous variables?

Answer 14

factors that can affect the behavior of participants
e.g light, noise or heat etc.
or emotional state of participants, sex, age etc.

Question 15

what are cofounding variables?

Answer 15

when extraneous variables ‘align’ themselves with he experimenter’s manipulation of the IV, they become cofounding variables

Question 16

what is meant by experimental control?

Answer 16

preventing extraneous variables from becoming cofounding variables

Question 17

what is a hypothesis?

Answer 17

a testable statement based on theory or observation, a prediction of the relationship between 2 variables, a prediction of the ‘cause an effect’

Question 18

what is an experimental (alternative) hypothesis?

Answer 18

this type of hypothesis tests the cause of independent variable on the effect of dependent variable

Question 19

what are the two types of experimental/alternative hypothesis?

Answer 19

directional (one-tailed)
non-directional (two-tailed)

Question 20

what is a directional hypothesis?

Answer 20

this hypothesis predicts the direction in which the results are expected to occur e.g ‘significantly more/less’

Question 21

what is a non-directional hypothesis?

Answer 21

this hypothesis doesn’t predict the expected direction of e outcome, but will state that there is a difference between the two states, the hypothesis does not specify if the behavior will be better or worse, just different

Question 22

what is a null hypothesis?

Answer 22

the counterpart to the experimental/alternative hypothesis.
‘no difference’ ‘no change’
if the null hypothesis can be rejected statistically, we can accept the experimental/alternative hypothesis

Question 23

what is experimental designs?

Answer 23

the researcher must decide whether the same participants will be tested in both conditions, or whether different participants will be tested in different conditions

Question 24

what does two levels of the IV mean?

Answer 24

two or more conditions in an experiment

Question 25

what is independent measures?

Answer 25

using different participants in each of the experimental conditions, the two groups will be exposed to different kinds of treatments. by comparing the performance from each group, you will be able o establish where the IV affects participants behavior.

Question 26

what are positives of independent measures?

Answer 26

- no order effects - high in validity = only experienced one IV - cost and time effective

Question 27

what are negatives of independent measures?

Answer 27

- more participants involved - low levels of individual differences = some people may have different abilities = lo in validity

Question 28

what are repeated measures?

Answer 28

comparison of people in one condition with their own performance in another condition, the same participants for both conditions.

Question 29

what are the positives of repeated measures?

Answer 29

- less participants - reduces time and cos - high levels of individuality differences = increases validity - can use the same task in all conditions = increases validity

Question 30

what are the negatives of repeated measures?

Answer 30

- participants have experienced both conditions of the iv, so hey either already have an advantage or the will become bored = decreases validity

Question 31

what are matched pairs?

Answer 31

the experiment matches individuals in either condition to another in the other condition e.g from their height, age or gender

Question 32

what are positives of matched pairs?

Answer 32

- high control over individual differences = increases validity - can use the same task in all conditions = increases validity

Question 33

what are the negatives of matched pairs?

Answer 33

- time consuming = you have to match participants - can be subjective in the choice of matching criteria

Question 34

how to prevent order effects?

Answer 34

counterbalancing, sample divided in half and he order is changed e.g A B A B A B = order effects balanced

Question 35

12 marker structure?

Answer 35

what - define in one sentence how - include as much replicable detail as you can (contextualise it) justify - why have you chosen to use this particular feature (give a strength in context) link - link it back to your own study that you did in your practical (explain why you are now doing a certain feature in this experiment)

Question 36

what should you do first in your 12 marker?

Answer 36

find the dv, and find the two levels of the IV

Question 37

what is in MB4 for the 12 marker?

Answer 37

- 3 x RFs - accurate and detailed knowledge and understanding of A01 - context - appropriate justifications and contextualised - good PEC - reference to your own link

Question 38

what experiment did we carry out?

Answer 38

whether it was easier to remember words or pictures more?