Research Methods

The major features of a science

• Objectivity

– (views based on observable phenomena not personal opinion, prejudices or emotion) = info verified by measurement based on empiricism (evidence comes from experiments not revelations)

• Replicability

– (ability for a procedure/findings to be repeated) = info is available to public scrutiny and any study should be able to be repeated and get the same info

• Controlled observations

– observing manipulation of IV = cause and effect

• Testing theoretical prediction

• Falsifiability

– theories disproved by evidence

• Paradigm

– the accepted theoretical orientation within a science

Science and non-science – Zechmeisteret al

Science

• Empirically based

• Collecting scientific info is systematic and controlled

• Reporting info is unbiased and objective

• Ideas/hypo can be tested

Non-Science

• Intuitive

• Non-scientific info is random and uncontrolled

• Reporting info can be bias and subjective

• Ideas/hypo cannot be tested

The scientific method – Popper’s research cycle

Identify a problemDevelop a hypothesis

Devise a study

Analyse and Evaluate

Modify and repeat the process =

previousDevelop a theory

The scientific method - Kuhn

Pre-Science Normal ScienceRevolutionary

Science

Scientists cling to theories despite contradictory evidence.More contradictory evidence = questioning the current paradigm and a new one put forward.

The new paradigm is accepted by the scientific community replacing the old.Progress of science is characterised by periods of normal a science and a period of revolutionary science

Unfalsifiabletheories become known as scientific laws

Validating new knowledge and the role of peer review

ResearchPrepare

manuscript

Send to journal/ editor

Send to psychological

experts = peer reviews

AssessmentSend back to editor with

comments and recommendations

Publication

Revised

Rejected

Problems of Validation

• Research that does not fit previous work is often rejected slowing revolutionary science– Garcia F: a CR could be established even after a 6 hour gap. This

was contradictory to all other work in classical conditioning. It was rejected several times before other studies began to show the same results

• Values in science, science tried to be objective but it cannot be separated from culture, politics or personal values.

• Bias in peer review such as gender, institution and theoretical bias

• File drawer phenomenon – peer review favours positive research

Selection of research methodIs the aim of the research to collect

descriptive data or to investigate links between variables

What sort of links,

relation/causal

Correlational Laboratory

Study behaviour of

groups/individuals

Case studyAsk for response/

or watch behaviour

observation

Large sample of info/detailed

survey interview

Research Methods - ExperimentalType Description Advantages Disadvantages

Laboratory •Controlling the variables(who, what, when, where and how). Using a standardised procedure.

•High degree of control = greater accuracy and objectivity•Repeatable•Can determine cause and effect

•Demandcharacteristics = participants try to guess the purpose and act accordingly•Low ecological validity = low generalisability to other settings

Field •Preformed in the real world with direct manipulation of the IV

•High ecological validity = generalisable to other settings•No demand characteristics = participants are unaware of the experiment

•Less control•Replicability = conditions will never be exactly the same•Sample bias = participants aren’t randomly allocated to groups

Natural •The IV occurs naturally, only record the effect on the DV

Experimental method - DesignsDesign Description Advantages Disadvantages

Repeated Same participants used in each condition

•Fewer participants•Participant variables are eliminated as each participant acts as their own control

•Order effects may occursuch as boredom but these can be controlled through counterbalancing•Cannot use the same materials in each condition

Independent Participants are randomly allocated to different groups representing different conditions

•No order effects•The same materials can be used in both conditions reducing production cost

•Participant variables introduced = differenced in condition may be due to the diff in part. Not IV•More participants required

Matched Pair of participants are closely matched and then randomly allocated to either one condition

•No order effects•Attempts to control participant variables

•Difficult to match part on everything therefore not eliminating part variables totally•More participants required

Research Methods - Correlational

• Strength of a relationship between 2 variables

• Expressed by the correlation coefficient(-1/+1)

• Advantages

– See if there is a sig. Relationship between 2 variables when it cannot be investigated experimentally

• Disadvantages

– No cause and effect

– Ambiguous

– Subjective

Research methods – ObservationalType of observation Description Advantages Disadvantages

Naturalistic The IV occurs naturally, the researcher only records the effect on the DV

•Natural behaviour is being observed•High in ecological validity

•Little control over confounding variables

Controlled Controls the variables which might influence behaviour

•Control over confounding variables

•Behaviour may not be natural/normal

Participants The observer becomes actively involved in the activities of the people being studied

•Easier to understand the observee’s behaviour•High ecological validity

•Hard to record observations(retrospectively therefore low reliability)•Observer can become involved with the participants and the data subjective

Non-participant Researcher observing from a distance

•Observations made as they happen = more reliable•Lack of contact so the observer can maintain objectivity

•Behaviour may be recorded by the meaning behind it unknown

Self report techniquesTypes Description Advantages Disadvantages

Surveys •Gather info about a topic from a large group of people•From Q.-Open/closed

•Large amount of info efficiently

•Low response rates = reducing validity•Social desirability

Interviews •Structured, unstructured,semi-structured

•More flexible as researcher can interact with the participant

•Subjective•Time consuming

Case study •In-depth study of an individual/ group

•Rich source of meaningful data

•Low population validity •Low Replicability= low reliability

Reliability = Consistency

Assessing reliability• External reliability = same results

every time– Test-retest method

– Correlation coefficient of 2 sets of scores

• Internal reliability = consistency of a measure within a test– Split half method = compares one

half of the test with the other to check whether the scores are consistent

– E.g. Taking scores from even samples and correlating them against with the odd scores

Improving reliability

• Take more than on measurement from each participant

• Pilot studies = method of measurement works properly and that part can use apparatus successfully

• Standardise collection and recording of data = inter-rater reliability

Validity = truth of a measure

Internal Validity - issues

• Internal = ability of a study to test the hypo that it was designed to test

• Confounding variables = V confused with the IV

• Demand characteristics

• Experimenter bias = the tendency of experimenters to find what the expect to find

Improving internal validity

• Single – blind = participants don’t know what group/condition they are assigned to = no demand characteristics

• Double – blind = neither the participant nor the researcher now the details of the group/condition = no demand characteristics or experimenter bias

Validity = truth of a measure

External validity - issues

• External = how well the results of a study can be generalised beyond the study itself– Population validity

– Ecological validity

Improving external validity

• Choose a representative sample = random sampling

Validity = truth of a measure

Assess validity

• Face validity = whether a test seems to be valid = weakest form

• Criterion validity = more objective– Concurrent validity = similar

finding to another existing measure

– Predictive validity = how well a test predicts future preformance

Internal vs External

• More CV controlled internal is high = artificial = reducing external

• Either high internal/external depends on the purpose of the study– Test a theory = high internal

– Real world application = high external

Issues of sampling

• When choosing a sample you want high population validity = representative of the target population = results can be generalised to the whole population

• Random sample has the highest pop validity but rarely used compared to volunteer/opportunity

• Conflict between the desire for good design and ethical guidelines

BPS Ethical guidelinesConsent Give informed consent

Deception Not misled

Debriefing Discuss investigation with part post

Withdrawal Feel free to leave

Confidentiality Right to confidentiality

Protection of participants Both psychological and physical

Observational research Privacy respected

Giving advice Only give advice for which they are qualified

Colleagues Make sure all colleagues are ethical too

Ethical processInformed consent via info sheet and

consent form

Info sheet = objectives of

study

Opportunity for Q. About info

Info stress that part can withdraw

Read and understand info before signing

Extra safeguards for those who have

trouble understanding

Full disclosure = demand

characteristics = low internal validity

Deception

Look for alternatives

Debrief and right to withdraw

data/retrospective consent

Prior general consent

Understanding, monitor unforeseen effects/disturbances

Should leave in the same state as

they entered

Probability and significance

• Probability/p = the number of outcomes/number of possible outcomes = 0-1(0=event won’t happen, 1= event will happen)– Level of significance – p ≤ 0. 05(less than 0.05 is significant = reject the null

hypothesis)

• Conditional probability = the probability of an event if something else occurs

• Statistical tests = how likely it is that what we have found in our sample accurately reflects what happen in the population– Alternate and null hypo = if the probability is small it suggest any pattern in

the sample is unlikely to be down to chance = reflect population = significant = reject null hypothesis

• Level of significance p ≤ 0.05 is chosen to balance the risk of type 1 +2 errors– Type 1(false positive) = when the null hypothesis is rejected but shouldn’t

have been– Type 2(false negative) = when the null hypothesis is accepted but shouldn’t

have been

Choosing a statistical testType of research design

Nature of hypothesis

Level of measurement

Independent (unrelated)

Repeated (related)

Differences Nominal Chi – square Sign test

Ordinal Mann-Whitney Utest

Wilcoxon (matchedpairs)

Interval Independent t test Related t test

Correlation Ordinal Spearman’s rho

Interval Pearson product moment

Chinese men drink tea

Sexy women read sexy porn

Dealing with quantitative data

Descriptive statistics –summarising data

• Data summarised using measures of central tendency and measures of dispersion

• Differences/relationships illustrated graphically

Inferential statistics – analysing the data

• Statistical tests– Choosing the right test

– Analyse and interpret the statistical findings

Summarising Data

• Measures of central tendency = compared data from two sets of scores– Mean, median, mode

• Measured of dispersion = describe the spread of scored/how much variation there is – Range/standard deviation

• Ways of summarising data = graphs– Histogram

• Shows distribution of a whole set of data//bars joined=continuous scale//column area = frequency of the score

– Bar chart• Bars aren’t joined = non-continuous scale//not all categories put x-axis

– Scatter grams• The relationship between two variables

Analysis and Interpretation of Qualitative data

Analysis(inductive and reflexivity)• Data collection and analysis are hard to

seperate• First stage = organising the data

– E.g. Recording speech = transcript• Know the data thoroughly = reading the

transcript a number of times• Code the data(depends on analysis)

– Interpretive phenomenological analysis» Interpreting the meanings of

events/experiences that have had an effect on the part.

– Grounded theory» Coding each line of text =

combine into larger constructs = explored and links between them studied

– Discourse analysis» Analysis of speech/written

discourse(investigates the social context of discourse and the interaction between speakers)

Evaluation/interpretation• Trustworthiness

– External audit• Check documentation, from

transcript to final analysis by an external party

• Documentation should include– How any decisions were

made

– Transferability = can the insights be transferred to similar situations

– Negative case analysis = exploring cases that do not fit the emerging concepts

– Reflexivity

ReportTitle

Abstract

Intro - hypo

Method –design,

participants, apparatus, procedure

Design = design used, number of groups/ conditions, variables, control measures(counterbalancing)Participant = features of the sample, how they were selectedProcedure = allocation of participants, how data was collected

results –descriptive/inferential, rejection/acceptance of

null hypo

Discussion –summary of

findings

References

To include

Aims/hypothesisAlternativeNull

Design•Either repeated, matched, individual groups•Number of conditions•Variables

•Independent•Dependent•extraneous(affect part)•confounding(confused with IV)

•Measures•Counterbalancing

•Participants•What demographics•How they are collected

•Procedure•How participants allocated•Collection of data

Results•Descriptive

•Measures of central tendency/dispersion•Graphs

•Inferential•Test significance

•Accept/reject the null hypothesis

Ethics and future directions