Cambridge International A Level Psychology: Research Methods

Psychology

the scientific study of behaviour and mental process

Biological Approach

examines how one's biology affects behaviour and mental processes

Cognitive Approach

examine human thought and behaviour in terms of how we interpret, process and remember events

Learning Approach

interested in how humans and animals learn

Social Approach

interested in how we work in the social world and looks at how individuals interact with each other and in groups

Nature

debate that result from innate, genetic factors

Nurture

debate that result from environmental influences

Aim

general statement about the purpose of an investigation

Hypothesis

Testable statement predicting a difference between levels of the independent variable or a relationship between variables

Null hypothesis

Testable statement saying that any difference or correlation in the results is due to chance that no pattern in the results has arisen because of the variables being studied

Non-directional hypothesis

A statement predicting only that one variable will be related to another that there will be a difference in the DV between levels of IV in an experiment or that there will be a relationship between the measured variables in a correlation. Also called two-tailed

Directional hypothesis

A statement predicting the direction of a relationship between variables in an experiment whether the levels of the IV wil priduce an increase or decrease in the DV or in a correlation whether an increase in one variable will be linked to an increase or a decrease in another variable. Also called one-tailed

Experiment

an investigation looking for a causal relationship in which an independent variable is manipulated and is expected to be responsible for changes in the dependent variable

Variable

condition that changes

independent variable

factor under investigation in an experiment which is manipulated to create two or more conditions and is expected to be responsible for changes in the dependent variable

Dependent variable

factor in an experiment which is measured and is expected to change under the influence of the independent variable

Extraneous variable

variable which either acts randomly, affecting the DV in all levels of the IV or systematically, ie. on one level of the IV so can obscure the effect of the IV, making the results difficult to interpret

Confounding variable

type of extraneous variable that affect the performance of participants

Situational variable

type of extraneous variable caused by an aspect of the environment

Operationalisation

definition of variables so that they can be accurately manipulated, measured or quantified and replicated. This includes the IV and DV in experiments and the two measured variables in correlation

Standardisation

keeping the procedure for each participant in an experiment exactly the same to ensure that any differences between participants or conditions are due to the variables under investigation rather than differences in the way they were treated

Sample

part of a population the group of people selected to represent the population in a study

Representative sample

sample that represent the population

Sampling technique

method used to obtain the participants for a study from the population

Opportunity sample

participants are chosen because they are available

Volunteer sample

participants are invited to participate. Also known as self-selected sample

Random sampling

all members of the population are allocated numbers and a fixed amount of these are selected in a unbiased way

Stratified sampling

grouping population into categories and choosing a sample where participants from each category match the proportions rom the population

Experimental condition

one or more of the situations in an experiment which represent different levels of the IV and are compared (or compared to a control condition)

Control condition

a level of the IV from which the IV is absent. It's compared to one or more experimental condition

Laboratory experiment

research method where there is an IV, a DV and strict controls. It looks for a causal relationship and is conducted in a setting that is not in the usual environment for the participants with regard to the behaviour they are performing

Demand characteristics

features of the experimental situation that gives away the aims. They can cause the participants to try to change their behaviour to match their beliefs about what is supposed to happen, which reduces the validity of the study

Random allocation

a way to reduce the effect of confounding variables. Participants are put in each level of the IV such that each person has an equal chance of being in any condition

Field experiment

investigation looking for a casual relationship in which an independent variable is manipulated and is expected to be responsible for the changes in the dependent variable. It's conducted in the normal environment for the participants for the behaviour being investigated

Generalisability

being able to apply findings of a study more widely to other settings and population

Natural experiment

investigation looking for a causal relationship in which the independent variable cannot be directly manipulated by the experimenter. Instead they study the effect of an existing difference or change. Since the researcher cannot manipulate the levels of the IV, it's not a true experiment

Experimental design

The way in which participants are allocated to levels of the IV

Independent measures design

an experimental design in which a different group of participants is used for each level of the IV

Repeated measures design

an experimental design where each participant performs in every level of the IV

Participant variables

individual differences between participants that could affect their behaviour in a study. They could hide or exaggerate differences between levels of the IV

Order effects

practice and fatigue effects are the consequence of participating in a study more than once. They cause changes in performance between conditions that are not due to the IS, so can obscure the effect on the DV

Fatigues effect

situation where participants' performance declines because they experience the experimental task more than once

Counterbalancing

used to overcome order effects in a repeated measures design. Each possible order of levels of the IV is performed by a different sub-group of participants. This can be described as an ABBA design as the participants do condition A then B and half of B then A

Matched pairs

experimental design where participants are arranged into pairs. Each pair is similar in ways that are important to the study and one member of each pair performs in a different level of the IV

Self reports

Research method that obtains data by asking participants to provide info about themselves

Questionnaires

Research method that uses written questions

Closed questions

Questionnaire that produce quantitative data. They only have a few, stated alternative responses abd no opportunity to expand on answers

Open questions

Questionnaire that produce qualitative data. Participants give full and detailed answers in their own words

Social desirability bias

Trying to present oneself in the best light by determining what a test is asking

Filler questions

Items put into a questionnaire to disguise the aim of the study by hiding the important questions among irrelevant ones so that participants are less likely to alter their behaviour by working out the aims

Interviews

Research method using verbal questions asked directly

Structured interview

Interview with quedtions in a fixed order which may be scripted. Consistency might also be required for the interviewer's posture, voice

Unstructured interview

interview in which most questions depend on the respondent's answers . A list of topics may be given to the interview

Semi-structured interview

Interview with fixed list of open and closee questions. Interviewer can add more questions if necessary

Case studies

detailed investigation of one instance, usually a single person. These may be rare or instances that could not be created artificially but can provide useful information. It uses a range of techniques

Naturalistic observation

Study conducted by watching the participants' behaviour in their normal environment without interference from researchers in either the social or physical environment

Unstructured observation

Study conducted by watching the participants' behaviour in a situation in which the socual or physical environment has been manipulated by the researchers. It can be conducted in either the participants' normal environment or in an artificial situation

Structured observation

Study in which the observer records only a limited range of behaviours

Behavioural categories

Activities recorded in an observation. They should be operationalized and should break continuous stream of activity into discrete recordable events. They must be ovservable actions rather than inferred states

Participant observer

Researcher who watches fron the perspective of being part of social setting

Overt

Role of observer is obvious to the participants

Covert

Role of observer is not obvious because they are hidden or disguised

Non-participant observer

Researcher who doesn't become involved in the situation being studied by watching through a one-way glass or by keeping apart from the social group of aprticipants

Correlation

Research method which looks for a causal relationship between two measured variables. A change in one variable is related to a change in the other

Correlation coefficient

number ranging from -1 to +1 that indicates the strength of correlation

Positive correlation

Relationship between two variables where both variables increase together

Negative correlation

Relationship between two variables where one variable increases while the other decreases

Quantative data

numerical results about the quantity of a psychological measure such as pulse rate or a score on an intelligence test

Qualitative data

descriptive, in-depth results indicating the quality of a psychological characteristic, such as responses to open questions in self-reports or case studies and detailed observations

Pilot study

preliminary test of procedures of a study that helps identify which variables will be important to control before the experiment starts. This helps the participants understand directions

Floor effect

all performance is low because the task was too difficult

Ceiling effect

all performance is high because the task is too easy

Ethical issues

problems in research that raise concerns about the welfare of paricipants

Ethical guidelines

pieces of advice that guide psychologists to consider the welfare of participants and wider society

Protection from harm

participants should not be exposed to any greater physical or psychological risk than they would expect in their day-to-day life

Informed consent

Knowing enough about a study to decide whether you want to agree to participate or not

Presumptive consent

When informed consent isn't available

Debrief

giving participants a full explanation of the aims and potential consequences of the study at the end of a study so that they leave in at least as positive a condition as they arrives

Deception

participants should not be deliberately misinformed about the aim or procedure of the study if this is unavoidable, the study should be planned to minimize the risk of distress, and participants should be thoroughly debriefed

Confidentiality

Participants' results and personal info should be kept safely and not released to anyone outside the study

Privacy

Participants' emotions and physical space should not be invaded, they should not be observed in situations or places where they would not be expected to be seen

Right to withdraw

A participant should know that they can remove themselves, and their data, from the study at any time

Replacement

researchers should consider replacing animal experiments with alternative and avoid research that causes pain and distress if possible

Validity

extent to which the researcher is testing what they claim to be testing

Reliability

extent to which a procedure, task or measure is consistent that it would produce the same results with the same people on each occasion

Test-retest reliability

a way to measure the consistency of a test or task. The test is used twice and if the participants' two sets of scores are similar it has good reliability

Inter-observer reliability

Consistency between two researchers watching the same events whether they will produce the same records

Ecological validity

extent to which the findings of research in one situation would generalise to other situations. This is influenced by whether the situation represents the real world effectively and whether the task is relevant to real life

inter-rater reliability

Extent to which two researchers interpreting qualitative responses in a questionnaire will produce the same records from the same raw data

Mundane realism

task is relevant to real life

Placebo

bogus treatment that has the appearance of being geniune. Designed to control for subjects' expectations

Blind study

conditions where the participants are unaware of the treatment

Double blind study

neither the subjects nor experiments know who has obtained the treatment