RESEARCH METHODS: KEY TERMS SECTIONS 1 Hypothesis 2 Variables 3 Sampling Techniques 4 Risk Factors 5 Reliability 6 Validity 7 Ethical Issues 8 Data Collection.

RESEARCH METHODS: KEY TERMS

SECTIONS1 Hypothesis

2 Variables

3 Sampling Techniques

4 Risk Factors

5 Reliability

6 Validity

7 Ethical Issues

8 Data Collection

Core Studies Loftus & Palmer Maguire

Baron-Cohen Piliavin

Savage-Rumbaugh Reicher & Haslam

Samuel & Bryant Rosenhan

Bandura Thigpen & Cleckley

Freud Griffiths

Dement & Kleitman Milgram

Sperry

KEY TERMSComplete key terms sheet for the following terms.

HYPOTHESIS EXTRANEOUS VARIABLE

OPPORTUNITY SAMPLE

VALIDITY

ALTERNATIVE HYPOTHESIS

SITUATIONAL VARIABLE

INTERVIEWER BIAS INTERNAL VALIDITY

NULL HYPOTHESIS PERSONVARIABLE

EXPERIMENTER BIAS SOCIAL DESIRABILITY

ONE TAILED HYPOTHESIS

EXPERIMENTAL VARIABLE

RELIABILITY QUALITATIVE DATA

TWO TAILED HYPOTHESIS

CONTROLING EXTRANEOUS VARIABLE

S

INTERNAL RELIABILITY

QUANTIATIVE DATA

VARIABLES SAMPLING EXTERNAL RELIABILITY

MEAN

INDEPENDENT VARIABLE

RANDOM SAMPLE

EXTERNAL VALIDITY MEDIAN

DEPENDENT VARIABLE

SELF-SELECTED (VOLUNTEER)

DEMAND CHARACTERISTICS

MODE

HYPOTHESIS•Alternative •Null •One tailed•Two tailed

‘there will be an

effect of x on y’

Experimental (alterative) HypothesisDefinition A statement of the relationship

between the IV and DV

Reasons for using

An alternative to the null hypothesis (accept/reject)

Null HypothesisAn assumption that there is no relationship (difference,

association, etc) in the population from which a sample is taken with respect to the variables being studied.

‘there will be no effect of x

on y’

Directional Hypothesis1 TAILED

Definition Predicts the effect/relationship

Reasons for using

Previous research suggests the direction

Non-directional hypothesis2 TAILED

Definition Does not predict the direction of the effect/relationship

Reasons for using

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

VARIABLES•Independent•Dependent •Situational •Personal•Experimenter•Extraneous

VariablesIndependent

Variable •Manipulated by the experimenter•Create different conditions

Dependent Variable

•Measures the consequence of IV manipulation

INGNEOUS

1. Situational variables are characteristics of the environment in which the experiment is being conducted which may have an effect on the results. The nature of these variables is very much dependent on the nature of the experiment but temperature, time and humidity could all be situational variables.

2. Person or Subject variables are inherent characteristics of the Experimental Unit that might affect outcomes. Hence examples of subject variables might include age, gender and other demographic details (among subjects) and x, y and z (among objects) although this is very much dependent on the object in the experiment.

3. Experimental variables are characteristics of the experimenter or the experimental team which might influence how the experiment is conducted, or how the experimental subject responds/behaves in the experimental setting. There is a wide definition for these variables and they may include age, gender, qualifications, etc.

Controlling EV

It is necessary to control extraneous variables so that results are not undermined by their effect (become confounding):

1. Control: Ensuring that an extraneous variable remains the same for all experimental units in the experiment. This requires that you are aware of the extraneous variable during the design stage and that you can control it.

2. Constant: Balance the variable across experimental groups This enables comparisons to be made between experimental units on the basis of the effect of the variable.

Sampling Method •Random •Self Selected (volunteer) •Opportunity

Sample Definition Selected to be representative of the

population

Evaluation May be biased ,therefore can’t generalise

PopulationDefinition The group of people whom the sample

is drawn

Evaluation May be biased

Random sampling Definition Every member of the population has an equal

chance of being selected

Advantage Potentially unbiased Most replicable

Disadvantage Needs to be drawn from a large population to be unbiasedDifficult to obtain

Participants for Psychological

Research

Volunteer Sample Self Selected

Definition •Participants become part of a study by volunteering

Advantage •Access to a variety of participants •Ethically sound

Disadvantage •Volunteer biased•Small sample

Are you available?

Opportunity Sample

Definition Selecting people who are more easily available

Advantage Easy to obtain

Disadvantage Very biasedNot replicable

FACTORS ASSOCIATED WITH RESEARCH DESIGN

•Control of extraneous variables •Interviewer bias•Experimenter bias •Standardisation

Any variables that change between conditions, other than the IV...

Control of Extraneous Variables

Investigator effect: Anything the investigator does which has an effect on a participant’s performance in a study

other then what was intended.

Interviewer bias The same in an interview situation, through, for example, leading questions and the ‘Green-spoon’ effect

Experimenter bias

The effect of an experimenter’s expectations, communicated unconsciously, on a participant’s behaviour

Standardisation

Instructions Pts told what to do in

exactly the same way.

Procedures Pts treated in exactly

the same way.

Reliability of Measurement•Internal •External

Validity•Internal •External

Kelly (1927) stated that a test is valid if it measures what it claims to measure. For example a test of intelligence should measure intelligence and not something else (such as memory).

Generalisability

The findings of any particular study should apply to the whole

population

Types of Validity

Experimental

Internal

External

MeasureConcurrent

Content

Validity: The legitimacy of a study Internal Validity

The extent to which the a measurement technique measures

what it is supposed to

Reasons for low internal validityDemand Characteristics: Features of an experiment the elicit a particular response form participants.Participant reactivity Extraneous variables not controlled (CV), act as an additional IV.Mundane realism: Do measures used generalise to real life > contribute to external validity

External Validity

Validity outside of the research situation,

extent to which findings can be

generalised

Assessing external validity How representative is the sample of participants of the population to which the results are to be generalised? Population VDo the research setting and situation generalise to a real-life setting or situation? Ecological VDo the findings generalise to the past and to the future? Historical V

Experimental

Internal

Extraneous

Mundane Realism

External

Ecological Validity

Population Validity

Historical Validity

Extraneous Variables

Situational Variables Participant Variables Investigator Effects

Demand CharacteristicsParticipant Effects

Participant reactivity: The fact that participants react to cues in an experimental situation

Hawthorne Effect Increased attention becomes a confounding variable

Demand Characteristics

Features of an experiment that a participant unconsciously, responds to when searching for clues about how to behave. A confounding variable.

Social Desirability bias

The desire to appear favourably

Validity of Psychological Measure

Concurrent Validity

How well does the measure agree with existing measures?- Test using old and new tests

Content Validity

Does the method used actually seem to measure what you intended? - Use a panel of experts

Measure

Concurrent

Content

Ethical Issues •Right to withdraw•Confidentiality •Protection from harm •Informed consent

Dealing with Ethical Issues

Presumptive…

A

B

C

Prior…

Dealing with informed consent

• Presumptive consent: Ask for others’ opinion and presume participants feel the same way.

• Prior general consent: Get participants to agree to take part in a number of studies, one of which they will be deceived in.

Dealing with Ethical Issues

Dealing with deception

• Debriefing: Inform participants of true nature of the study after it is conducted and allow them to discuss their feelings.

• Right to withhold information

• Cost and benefits: Deception is acceptable if the benefits are sufficient.

Dealing with Ethical Issues

Dealing with protection from psychological harm

• Anticipating harm and stopping

• Using role-play

• Use of questionnaires: Ask people how they would behave.

• Debriefing

Data• Types: Quantitative & Qualitative • Measures of central tendency: mean, median, mode• Graphical representations

Data Collection Quantitative

Data Easy to analysis

Produces neat conclusions

Oversimplifies reality

Qualitative Data

Represents the complexity of human behaviour

Provides rich data

More difficult to detect patterns and reach conclusions

Subjective, affected by personal expectations and beliefs

2,4,4,5,6,6,7,78,8,8,8,8

9,10,11,11,12

Measures of Central Tendency Mean: Add

values, divide by number of

values

Makes use of all the data

Can be misrepresentative if there are extreme values.

Median: Middle value in an

ordered list

Not affected by extreme scores

Not as ‘sensitive’ as the mean

Mode: The most common value(s)

The mist common value(s)

Not useful when there are several modes

Graphs & Charts

Histogram Graph showing continuous frequency data with a true zero e.g Exam results 0-30marks

Bar Charts Graph showing frequency data; data need not be continuous e.g. Categories

Scattergraph For correlations. Scatter of dots; each dot represent one case