2.2.1-2.2.10 Experiments

Question 1

‘Experiment’ definition

Answer 1

A scientific procedure undertaken to test a hypothesis in order to demonstrate causal relationships

Question 2

Outline what a ‘Lab Experiment’ is

Answer 2

-experiment where the researcher directly manipulates the IV to see the effect on the DV
-occurs in a controlled, artificial environment (control noise, space, temp)
-participants sign up

Question 3

Outline what a ‘Field Experiment’ is

Answer 3

-experiment where the researcher directly manipulates the IV to see the effect on the DV
-occurs in a natural environment such as a school or a shopping centre
-experimenter goes to participants

Question 4

Weaknesses of a Lab Experiment

Answer 4

-expensive to conduct
-participants are likely to guess aim and therefore demonstrate desired characteristics
-difficult to recruit participants
-time consuming to conduct
-low in external validity

Question 5

Strengths of a Lab Experiment

Answer 5

-very scientific as it occurs in a controlled environment
-high repeatability and reliability as the same procedure is usually used for all participants
-participants can usually always give informed consent
-groups can be randomally allocated (no experimenter bias)
-high in internal validity (control of extraneous variables)

Question 6

Weaknesses of a Field Experiment

Answer 6

-does not have full control over variables so not easy to repeat
-may not be able to gain informed consent
-sample could be unreppresentative
-low internal validity

Question 7

Strengths of a Field Experiment

Answer 7

-shows natural behaviour but is also controlled
-high generalisability
-easy to gain participants
-participants won’t guess aim
-high in ecological validity

Question 8

‘Hypothesis’ Definition

Answer 8

A statement that predicts the outcome of the results

Question 9

‘Opeerationalisation’ Definition

Answer 9

Making the variable clear and precise by giving detail about the study

Question 10

‘Experimental Group/Condition’ definition

Answer 10

The group who experiences the manipulated IV to see if it has any effect

Question 11

‘Control Group/Condition’

Answer 11

the group that experiences no manipulation in IV, so it acts as a baseline for comparison

Question 12

‘Experimental/Alternative Hypothesis’ definition

Answer 12

Hypothesis that states a relationship or difference between variables

Question 13

‘Null Hypothesis’ definition

Answer 13

States that there is no relationship or difference between variables

Question 14

‘Directional/One tailed Hypothesis’ definition

Answer 14

States the direction of the results thats expected (eg. higher, worse)

Question 15

‘Non-Directional/Two Tailed Hypothesis’ definition

Answer 15

Does not predict the direction of results

Question 16

‘Experimental Design’ definition

Answer 16

how participants are allocated to different groups in an experiment

Question 17

‘Independent Measures’ definition

Answer 17

when different participants are used in each condition of the IV

Question 18

Evaluate Independent Measures

Answer 18

Strengths: each participant takes part in 1 condition so therefore won’t guess the aim
Weaknesses: individual differences affect results, large group sizes are requires

Question 19

‘Repeated Measures’ definition

Answer 19

when the same participants take part in each condition of the IV

Question 20

Evaluate Repeated Measures

Answer 20

Strengths: eliminates individual differences, can have a small sample
Weaknesses: could guess the aim of research, could demonstrate order effects

Question 21

‘Matched Pairs’ definition

Answer 21

pairs of participants are matched across groups in terms of key variables

Question 22

Evaluate Matched Pairs

Answer 22

Strengths: overcomes individual differences
Weaknesses: difficult to find matched pairs, time consuming

Question 23

‘Order Effects’ definition and examples

Answer 23

The effects or doing multiple trials in a repeated measures design eg. tiredness, practice

Question 24

‘Counterbalancing’ definition

Answer 24

Steps that are taken to minimise the impact of order effects.
The participant sample is divided in half, with each half completing the two conditions in different orders

Question 25

'Random Allocation' Definition

Answer 25

When participants are randomally allocated to the conditions in order to avoid bias and participant variables

Question 26

'Extraneous Variables' definition

Answer 26

Variables that may affect results when they are not controlled for eg. alcohol consumption

Question 27

'Confounding Variables' definition

Answer 27

Variables that impact the IV and DV as they aren't controlled for eg. smoking

Question 28

'Participant Variables' definition

Answer 28

Characteristics of those taking part eg. IQ

Question 29

'Situational Variables' definition

Answer 29

Environmental factors that can affect the research

Question 30

'Experimenter Effects' definition

Answer 30

Things about the experimenter that affect the results, rather than the change in IV A weakness of matched pairs eg. gender, age, clothing

Question 31

'Experimenter Bias' definition

Answer 31

When the experimenter's beliefs or aims interfere with the results Resolved by using a 3rd party

Question 32

'Single Blind Trial' definition

Answer 32

When the participant doesn't know which group they're in, but the researcher does

Question 33

'Double Blind Trial' definition

Answer 33

when neither the experimenter or the participants know which group they're in

Question 34

'Objectivity' definition

Answer 34

A conclusion that's based on scientific facts and observations that are provable and measurable

Question 35

'Subjectivity' definition

Answer 35

A conclusion that's affected by bias assumptions, beliefs and emotions

Question 36

'Reliability' definition

Answer 36

The idea of consistency or replicability, results for a test should always be the same

Question 37

'Inter rater reliability' definition

Answer 37

when two or more individuals have a high agreement on a score and therefore the measurement of behaviour is reliable

Question 38

'Test retest reliability' definition

Answer 38

Testing multiple times to measure stability

Question 39

'Standardised Procedure' definition

Answer 39

When the procedure is the same for every participant

Question 40

'Validity' definition

Answer 40

whether a result is true and whether the investigation measures what it's supposed to measure

Question 41

'Internal validity' definition

Answer 41

a measure of whether results are affected only by changes to the IV

Question 42

'Construct Validity' definition

Answer 42

Whether a measure successfully measures what it's intended to

Question 43

'Concurrent Validity' definition

Answer 43

extent to which the test correlates with a measure that's been tested previously

Question 44

'Predictive Validity' definition

Answer 44

If a test accurately predicts a future outcome

Question 45

'External Validity' definition

Answer 45

a measure of whether the results can be generalised to situations outside of the one thag it's measured in

Question 46

'Population Validity' definition

Answer 46

Whether the results can be generalised to a larger population

Question 47

'Ecological Validity' definition

Answer 47

Whether data is generalisable to the real world

Question 48

'Mundane Realism' definition

Answer 48

How similar materials and procedures in an experiment are to real world events

Question 49

'Sampling' definition

Answer 49

Process of selecting subjects to study from the target population, should be as representative as possible and of a sufficient size

Question 50

'Random Sampling' definition

Answer 50

Participants are selected by chance, everyone has an equal chance of being selected, requires a method of numbering people

Question 51

'Opportunity Sampling' definition

Answer 51

Researcher asks who is available at the time

Question 52

'Systematic sampling' definition

Answer 52

Researcher divides target population into sections and takes an equal proportion from each group

Question 53

'Self selected' definition

Answer 53

Participants take part because they volunteer, for example by responding to an advert

Question 54

Evaluate 'Random Sampling'

Answer 54

Strengths: represents target population, eliminates sample bias, can be representative Weaknesses: time consuming, lots of effort, expensive, requires small groups

Question 55

Evaluate 'Opportunity Sampling'

Answer 55

Strengths: quick and easy, doesn't require much time or effort Weaknesses: not always reflective, experimenter bias

Question 56

Evaluate 'Volounteer Sampling'

Answer 56

Strengths: will comply with experiment, less work for experimenter, no experimenter bias Weaknesses: not always representative as a certain type of person will volounteer

Question 57

Evaluate 'Stratified Sampling'

Answer 57

Strengths: highly representative, results can be generalised, can be done on small scale Weaknesses: time consuming and difficult, rarely used, involves calculations and recruitment