Experimental Methods

Question 1

Where are experiments carried out?

Answer 1

In a controlled setting.

Question 2

What can experiments allow?

Answer 2

They allow us to establish cause and effect relationships because of this control.

Question 3

What are the 4 types of experiment?

Answer 3

Laboratory, field, quasi and natural experiments.

Question 4

What is a variable? Give an example.

Answer 4

A variable is something that varies:

E.g. How long you sleep each night is a variable. The number of days in a week isn’t, as it is fixed.

Question 5

What is the dependent variable?

Answer 5

The variable you measure. Affected by the independent variable.

Question 6

What is the independent variable?

Answer 6

Directly manipulated by the experimenter.

Question 7

What does the experimenter decide about the IV and the DV?

Answer 7

The experimenter will decide whether or not the IV caused a change in the DV.

Question 8

What is operationalisation?

Answer 8

How variables are defined and measured.

Operationalising definitions, means that they have contextualised it to suit their experiment.

Question 9

How did Schaffer and Emerson operationalise attachment?

Answer 9

Stranger Anxiety.

Separation Protest.

Question 10

What was the IV and DV in Jacobs’ study? Baddeley? Peterson et al?

Answer 10

Jacobs:
IV: Capacity, digit-span length.
DV: Number of numbers recalled.

Peterson and Peterson:
IV: Duration, trigrams and time-span.
DV: Whether they recall 100% of the trigram.

Baddeley:
IV: Word lists.
DV: Number of substitution errors, how many words were recalled correctly.

Question 11

Why is control an important aspect in experiments?

Answer 11

Allows the study to conclude cause and effect, meaning you can assume the only variable causing the change in the DV is the IV.

Increases repeatability, this reduces chance and luck.

Reduces extraneous variables.

Question 12

What is experimental control? Give an example.

Answer 12

All other variables other than IV and DV must be controlled (kept constant.

This is very important, as we are then able to assume that the only variable causing the change in the DV is the IV.

E.g. Baddeley (encoding in STM and LTM) would have had to make sure both words lists had words of the same length, frequency of occurrence in the language etc.

Question 13

Outline characteristics of a laboratory experiment.

Answer 13

Controlled.

Artificial.

Lacks mundane realism.

Results deemed objective.

Question 14

Outline 2 strengths of a laboratory experiment.

Answer 14

Can establish cause and effect relationships.

IV = cause, DV = effect.

Replicability (can repeat and achieve same findings).

More objective than other research methods.

Question 15

Outline 2 weaknesses of a laboratory experiment.

Answer 15

Often lack mundane realism.

Often lack ecological validity.

Often lack experimental realism.

Participants often know they are being observed (respond to demand characteristics).

May cause evaluation apprehension for participants.

Question 16

Outline two ethical issues that need to be considered when conducting laboratory experiments.

Answer 16

Phobias must be catered for. (E.g. severe phobias can spark anxiety/ depression).

Allergies must be catered for. (E.g. dogs may cause rashes or severe reactions).

Religion must be catered for. (E.g. Muslim women must have the right to keep their hijab on).

Conditions must be catered for. (E.g. flashing lights may cause epilepsy).

Question 17

Outline characteristics of a field experiment.

Answer 17

Carried out in natural settings such as in the street, in a school, at work etc.

The IV’s are still deliberately manipulated by the researcher.

Participants are not often aware that they are participating in an experiment.

Question 18

Outline Shotland and Straw’s 1976 field experiment.

Answer 18

A man and a woman (confederates) staged an argument and a fight fairly close to a number of bystanders.

In one condition, the woman screamed, “I don’t know you!”.

In another condition, the woman screamed, “ I don’t know why I ever married you!”.

The experiment found that people were less likely to lend a helping hand when it was a ‘lovers’ quarrel than when it was not.

Question 19

Outline 2 strengths of a field experiment.

Answer 19

Higher ecological validity than laboratory experiments as behaviour occurs in its own natural environment.

Less bias from sampling (subjects do not have to be bought into the lab).

Lower demand characteristics (if subjects are unaware of being tested).

Question 20

Outline 2 weaknesses of a field experiment.

Answer 20

Researchers have less control over extraneous/confounding variables, reducing confidence in establishing causal relationships.

It is difficult to replicate the research, making it hard to determine the results’ reliability.

Question 21

Outline two ethical issues that need to be considered when conducting field experiments.

Answer 21

It’s almost impossible to offer participants the right to withdraw.

You cannot directly ask the participants for consent before it is conducted.

Debriefing should be altered to fit the possible severity of the experiment. (E.g. A small, quick debrief may not be appropriate in catering for the participants if the study was impactful, such as a fight).

Question 22

When is a quasi experiment used?

Answer 22

When it is impossible or unethical to randomly allocate participants or manipulate the independent variable.

Question 23

What are quasi experiments? Give an example.

Answer 23

A quasi-experiment is any study where the independent variable cannot be manipulated by the experimenter (e.g. gender, culture, IQ).

For example, to conduct a study on the effects of smoking, you would not be able to randomly allocate people to groups - these groups are pre-existing.

Question 24

What can the researcher not control in a quasi experiment?

Answer 24

Manipulation of the independent variable is often not under the control of the experimenter.

Not possible to allocate participants randomly to groups in quasi-experiments.

Question 25

Outline 2 strengths of a quasi experiment.

Answer 25

Investigates the effects of independent variables that it would be unethical or impossible to manipulate.

Participants behave naturally.

Question 26

Outline 2 weaknesses of a quasi experiment.

Answer 26

Independent variable is not manipulated by the experimenter.

Participants are not randomly allocated to conditions.

Difficult to identify what aspects of the independent variable have caused the effects on the behaviour.

Requires ethical sensitivity.

Question 27

What are natural experiments?

Answer 27

A type of quasi-experiment.

Use of a naturally occurring event for research purposes as opposed to pre-existing groups.

For example, research of the effects of stress after a natural disaster or bereavement would be carried out using a natural experiment.

Question 28

What can the researcher not control in a natural experiment?

Answer 28

Changes in the IV are natural - the experimenter has no control over it.

Question 29

Outline Kario et al’s natural experiment from 2003.

Answer 29

Studied the effects of the Kobe earthquake (17/01/1995),in which 6,400 people died.

Measured stress levels in people who lived closest to the centre of the earthquake.

The increase rates of heart attacks and sudden death were measured 24 hours after the earthquake.

Question 30

Outline 2 strengths of a natural experiment.

Answer 30

Participants are often not aware they are taking part in an experiment.

Allow us to study the effects on behaviour of independent variables that it would be unethical for the experimenter to manipulate.

Question 31

Outline 2 weaknesses of a natural experiment.

Answer 31

Participants have not be assigned at random conditions.

Independent variable not controlled.

Cannot make causal inferences.

No ethical issues as the experimenter is not responsible for participants being exposed to IV.

Voluntary informed consent - participants are not aware that they’re taking part in research.

Sensitivity - experimenter needs to be sensitive to the situation.