Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Psychology: Cognitive > 09. Research Methods- Experiments > Flashcards

09. Research Methods- Experiments Flashcards

You may prefer our related Brainscape-certified flashcards:
Psychology 101 flashcards GRE® Psychology flashcards AP® Psychology flashcards
1
Q

What is an independent variable?

A

Variables that the experimenter changes/manipulates to test their dependent variable.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the dependent variable?

A

What you measure in the experiment and what is affected during the experiment. The dependent variable responds to the independent variable.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does the control of variables allow for?

A

Causality to be established (cause and effect).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does reliability refer to?

A

Consistency of measures.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does validity refer to?

A

Accuracy of measures.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define operationalisation.

A

Turning abstract ideas into numerical measurable observations.

(Eg measure stress using a heart rate monitor-bpm).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the two types of hypotheses?

A

Null:
-Any effect is due to chance, not the IV (there will be no relationship/difference).

Alternative:
-States there will be a difference due to the manipulation of the IV.
-Referred to as experimental hypothesis when the experimental method is used.
-Can be 1 tailed/directional OR 2 tailed/non-directional.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define directional hypothesis- 1 tailed.

A

Direction of results is predicted.
(Eg ‘women are better than men’).

Reason for using:
-Previous research suggests the direction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define non directional hypothesis- 2 tailed.

A

Change/difference is predicted, but not the direction it will go in.
Results can go in either direction.
(Eg ‘there will be a difference in male and female performance in a driving test’).

Reason for using:
-Allows for a difference/relationships occurring in either direction.
-Previous research has been inconclusive.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Define extraneous variables.

A

-Extraneous variables are variables that may have an affect on the dependent variable and confuse the results.
-They must be controlled in a study to ensure internal validity is high.
-Extraneous variables should be kept constant, so they affect each participant equally.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 2 types of extraneous variables?

A
  1. Situational variables
  2. Participant variables
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define situational variables.

A

An extraneous variable from the environment in which the study is conducted that might affect the results of a study.

Eg: Lighting, noise, temperature, time of day, other people.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define participant variables.

A

An extraneous variable from the participants themselves that might affect the results of the day.

Eg: Personality, age, intelligence, motivation, experience/skill.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Define confounding variables.

A

-Confounding variables are variables that may have caused the results other than what was manipulated (the IV).
-This is because confounding variables vary systematically with the independent variable.
-This means experimenters cannot be sure the change in the DV was caused by the IV.
-This means confounding variables acts as another IV.

(An experiment that fails to take a confounding variable into account is said to have poor internal validity because the experimenter is no longer measuring what they intended- the effect of the IV on the DV)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe lab experiments.

A

Lab experiments are conducted in a controlled setting. All of the extraneous variables are controlled, and the independent variable is the only one that changes. The independent variable is manipulated to cause an effect on the dependent variable-which is being measured.

(IV manipulated to observe the effect on DV, under controlled conditions. All other variables are controlled).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is an advantage of lab experiments?

A

-High internal validity due to high levels of control- cause & effect.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a disadvantage of lab experiments?

A

Low ecological validity as the setting is too controlled.
-If artificial task used, low mundane realism, decreasing task validity.
-Low internal validity as participants know they are taking part.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe field experiments.

A

Field experiments are conducted in a natural setting. Some extraneous variables cannot be controlled due to the unpredictability of the real-life setting, but an independent variable will still be altered for a dependent variable to be measured against.

(Aims to investigate casual relationships in more natural surroundings. IV is manipulated to observe the effect on the DV, in a natural setting. Some variables are controlled).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is an advantage of field experiments?

A

-High ecological validity as the setting is natural.
-If everyday task used, high mundane realism, increasing task validity.
-If participants are unaware they are taking part, high internal validity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is a disadvantage of field experiments?

A

-Low internal validity due to less control- cause & effect less likely.
-Low reliability as difficult to replicate procedure exactly.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Define independent groups design.

A

Two separate groups of participants that experience two different conditions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is a weakness of independent groups design?

A

-Participant variables may affect results (eg different ages in each condition)
-More participants are needed, takes longer to obtain sample, the study may take longer or be more difficult to carry out, ie doing the second condition on another day.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is a strength of independent groups design?

A

-No orders effects
-Less likely that demand characteristics will affect results

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Define repeated measures.

A

All participants experience all of the conditions of the experiment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Define matched pairs.

A

Two separate groups of participants that are paired on a specific characteristic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is a strength of repeated measures?

A

-Participant variables are less likely to affect results and fewer participants are needed.
-More data can be gathered in a shorter space of time as each person takes part in both conditions (not as time consuming or costly).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is a weakness of repeated measures?

A

-Order effects may affect results as participants are repeating conditions- fatigue, practice, boredom, etc.
-More likely for demand characteristics to be an issue, they may be able to guess the aim if they are exposed to more than one condition.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the purpose of a control group?

A

There will always be at lest two conditions in an experiment:
-Experimental condition
-Control condition

-A control group is used to establish a baseline to compare the results of the experimental group.
-Having a control group helps to rule out any extraneous variables.
-Experimenters compare the experimental group to the control group to determine if the manipulation of the IV had an effect- they are looking for a difference in the DV between the two groups.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is a strength of matched pairs?

A

-Participant variables are less likely to affect results as these have been controlled.
-No order effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is a weakness of matched pairs?

A

-Matching participants can be difficult, time consuming and expensive.
-More participants are needed, takes longer to obtain sample.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Define order effects (repeated measures).

A

-Order effects can occur in an experiment if a repeated measures design is used.

It is when the order of the conditions effects participant performance:
-A participant may perform better in the second condition because of experience (practice effect).
-A participant may perform worse in the second condition because of boredom or tiredness (fatigue effect).

This is a problem because it impacts on the dependent variables and reduces internal validity.

32
Q

How can experimenters deal with order effects?

A

Counterbalancing:

We can’t eliminate order effects, but we can control for them/balance them out by changing the order of the conditions.

This is called counterbalancing and uses that each condition is tested first or second in equal amounts.

-A counterbalanced design controls for order effects, we use separate groups of ppts, each group experiencing the conditions in a different order.
-This means the effects of practice or the impact of fatigue cancel each other out as an equal number of ppts experience both condition A and condition B last.

For example:
Group 1→A→B→Test
Group 2→B→A→Test

33
Q

Why is randomisation necessary when using an independent measures design?

A

-When using independent measures design, there is a lack of control over ppt variables.
-This means differences/characteristics between the 2 groups of ppts may not be equal, eg ppts in group A may be more intelligent than those in group B.
-This can be dealt with using randomisation of ppts to conditions, ie allocating ppts to groups using a random technque.
-This should balance out the differences and make the two groups more similar as ppt variables should not be clustered in one group.

34
Q

What is internal validity concerned with?

A

-If the researcher has measured what they set out to measure (IV effecting the DV).
-If the procedure established cause and effect between the IV and DV.
-If the results have been confounded by uncontrolled extraneous variables.

35
Q

How can low internal validity be avoided?

A

-Ensure there is objectivity (impartial/judgement free/unbiased).
-High levels of control for: extraneous variables, participant effects, investigator effects and order effects.
-Participant behaviour should be as natural as possible.

36
Q

How can internal validity be assessed?

A

Predictive validity:
The extent to which a test score is actually related to the behaviour you want to measure. The test score should forecast performance on another measure of the same behaviour

Such as if an IQ test can accurately predict future success in exams. These two variables should give a positive correlation to confirm the predictive validity of the test.

37
Q

What are investigator effects?

A

-Anything the investigator does which has an effect on a participant’s performance in a study other than what was intended.
-These can be the presence of the researcher or cues/signals from the experimenter that can be verbal such as tone of voice, or non-verbal such as facial expressions.

(They may influence the dependent variable, therefore decreasing the internal validity).

38
Q

How can investigator effects be controlled for?

A

-Double blind technique.
-No expectations so behaviour is natural.
-High validity.

39
Q

What is experimenter bias?

A

-This is a kind of investigator effect.
-The effect of an experimenter’s expectations on a participant’s behaviour.

40
Q

What are participant effects?

A

-The fact that participants react to cues in an experimental situation.
-These include responding to demand characteristics.

41
Q

What are demand characteristics?

A

Features of an experiment that a participant unconsciously responds to when searching for cues about how to behave. They may alter their behaviour by trying to please the experimenter or behave in a way that is unexpected.

(This may influence the dependent variable, therefore decreasing the internal validity).

42
Q

What is external validity concerned with?

A

How well the findings can be generalised or applied beyond the study:
-To other situations (ecological validity)
-To real-life tasks (task validity)
-To other populations (population validity/generalisability)

43
Q

How can low external validity be avoided?

A

-The context should be realistic, eg everyday setting if possible.
-The task should have mundane realism.
-The sample should be representative of the target population.
-Participant behaviour should be as natural as possible.

44
Q

How can low external validity be dealt with?

A

Triangulation:
Compare the results of multiple experiments with varying levels of control. If findings are similar this suggests conclusions drawn are valid.

45
Q

What is reliability concerned with?

A

It is an important part of the scientific process and refers to the replicability of research and the consistency of findings from research.

46
Q

How can low reliability be avoided?

A

-Research must be replicable.
-Procedures must be standardised.
-Procedure must be consistent for all participants.
-Extraneous variables must be controlled.

47
Q

How can reliability be assessed?

A

Test-retest:
If findings are consistent, then we can trust the same or similar findings will happen again and again (ie if we get consistency over time).

48
Q

Explain a single-blind technique.

A

The participants are not aware of what is expected or the condition they are in. But person carrying out the study is aware.

49
Q

Explain a double-blind technique.

A

-Neither the participant nor the person running the study knows what is expected.
-The participants are not aware which group they are in or what the study is about. The study is carried out by someone other than the experimenter.
-This will prevent experimenter bias.

50
Q

How do single and double blind-techniques control the issues of participant effects?

A

Deception to prevent the participants having expectations about the study to ensure behaviour is natural (aim and/or conclusions are unknown).

51
Q

What is a placebo condition?

A

Control group thinks it is receiving the experimental treatment.

(Participants more likely to behave naturally)

52
Q

What are standardised instructions?

A

A set of instructions that are the same for all participants. To avoid participants picking up on subtle cues from experimenters and to ensure all participants have the same experience.

53
Q

What is internal validity?

A

-Internal validity is about what’s going on inside the experiment.
-Has the researcher measured what they intended to measure.
-Have extraneous variables been controlled.
-Has cause and effect been established.

54
Q

How can low internal validity be avoided?

A

-Ensure there is objectivity (impartial/judgement free/unbiased).
-High levels of control for: extraneous variables, participant effects, investigator effects and order effects.
-Participants behaviour should be as natural as possible.

55
Q

How can internal validity be assessed?

A

Predictive validity:
-The extent to which a test score is actually related to the behaviour you want to measure. The test score should forecast performance on another measure of the same behaviour.

(Eg if an IQ test can accurately predict future success in exams. These two variables should give a positive correlation to confirm the predictive validity of the test)

56
Q

What is external validity?

A

External validity is how well the findings can be generalised or applied beyond the study:
-To other situations (ecological validity).
-To real life tasks (task validity).
-To other populations (population validity and generalisability).

57
Q

How can low external validity be avoided?

A

-The context should be realistic (eg everyday setting if possible).
-The task should have mundane realism.
-The sample should be representative of the target population.
-Participants behaviour should be as natural as possible.

58
Q

How can low external validity be dealt with?

A

Triangulation:
-Compare the results of multiple experiments with varying levels of control. If findings are similar this suggests conclusions drawn are valid.

59
Q

What is reliability?

A

Reliability is an important part of the scientific process and refers to the replicability of research and the consistency of findings from research.

60
Q

How can reliability be assessed?

A

Test-retest:
-If findings are consistent than we can trust the same or similar findings will happen again and again (ie if we get consistency over time).

61
Q

How can low reliability be avoided?

A

-Research must be replicable.
-Procedure must be standardised.
-Procedure must be consistent for all participants.
-Extraneous variables must be controlled.

62
Q

What is falsification?

A

-The attempt to prove something wrong.
-This involves the use of the null hypothesis which we seek to disprove within set bounds of certainty.

63
Q

Describe inferential testing.

A

-To make sense of the data produced by a research study, it must be analysed.
-This can be achieved using descriptive statistics (eg graphs).
-Inferential tests allow researchers to make inferences (deductions) about whether differences in data are significant ones (beyond the boundaries of chance) and therefore useful to the scientific community.

64
Q

Describe the concept of significance level.

A

-All studies employ a significance level in order to check for significant differences or relationships.
-The accepted level of probability is p<0.05
-This is the level at which the researcher decides whether or not to reject the null hypothesis and accept the research hypothesis.

65
Q

Describe probability in psychology.

A

-The p (probability) value determines whether or not we reject the null hypothesis.
-We use it to determine whether or not we think the null hypothesis is false (falsification).
-The p value provides an estimate of how often we would get the obtained result by chance, if in fact the null hypothesis were true.

66
Q

Describe the meaning of p<0.05 significance and probability.

A

-There is less than 5% probability the result occurred by chance, if the null hypothesis is true.
-Therefore if alternative hypothesis is true, this happens 95% of the time due to the IV.
-This means researcher can be pretty certain that the difference (or correlation) found was because of the manipulation of the IV with only a 5% doubt that it occurred only by chance.

67
Q

Why do psychologists commonly use a p<0.05 level of significance?

A

-Psychologists often use a p<0.05 level of significance to strike a balance between making a type 1 and type 2 error.
-Good compromise.
-If they use p<0.10 they may make a type 1 error but if they use p<0.01 they may make a type 2 error.

68
Q

When do researchers need to use p<0.01?

A

-The p<0.01 significance level is used when research may involve a risk to life, such as when new drugs are trialled, for socially sensitive topics or if the research is a one off and cannot be repeated.
-Researchers need to be more confident that results were not due to chance and so use a stricter, more stringent significance level.

69
Q

Define the null hypothesis (H0)

A

The prediction that states there will be no significant difference/correlation.

70
Q

Define the alternative hypothesis (H1)

A

The prediction that states there will be a difference/correlation. Can be directional or non-directional.

71
Q

How does a type I error happen?

A

-Results are wrongly found to be significant.
-Because researcher rejected the null (accepting the alternative) when actually, the result was due to chance.

72
Q

How does a type II error happen?

A

-Results are wrongly found to be not significant, just down to chance.
-Because the researcher wrongly accepted the null hypothesis (reject alternative) when actually the result was caused by the IV.

73
Q

When is a type I error likely to occur?

A

-When P<0.10 because the probability level is too lenient.

74
Q

When is a type II error likely to occur?

A

-When P<0.01 because the probability level is too stringent.

75
Q

What is the difference between type 1 and 2 errors?

A

-Type 1= False positive. Appearing significant when results are actually insignificant. Incorrectly rejecting the null.

-Type 2= False negative. Appearing insignificant when results are actually significant. Incorrectly accepting the null.

Psychology: Cognitive (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions