Research Methods

empirical evidence

scientific evidence obtained by careful observation and experimentation

scientific method

hypothesis formulation, testing, and retesting through processes of experimentation, observation, measurement and recording

aim

a statement outlining the purpose of the investigation

hypothesis

a testable prediction about the outcome of an investigation

controlled experiment

an experiment in which the relationship between two variables is tested, and all other variables are sought to be controlled

independent variable

the variable which is manipulated by the researcher to see the effect on the DV

dependent variable

the variable the researcher measures for changes

operationalised variable

precise specific definition of variable

controlled variable

variable other than the IV that is held constant by the researcher to ensure any changes to the DV are solely due to the IV

case study

an investigation of an individual, group, or phenomenon which includes complexities that would be encountered in the real world

correlational study

a non-experimental study where researchers measure the relationship between variables without actively controlling or manipulating them

observational study

a type of correlational study where a researcher passively watches participants with no active participation or intervention

longitudinal study

a type of study involving repeated observation of participants over a long period of time at specified time intervals

cross-sectional study

a type of study which collects data about a specific group of people at one point in time

classification

creating labels or groups for phenomena that may help to provide some functional or theoretical benefit

identification

recognising phenomena as belonging to a particular group or possibly being part of a new set

fieldwork

research involving observation and interaction with people and environments in real-world settings

literature review

collating and analysing secondary data from scientific findings, in order to help provide information about an observation or research theory

modelling

creating a physical or conceptual model to help represent a system that may better help people understand that system

product, process or system development

the design or evaluation of an artefact, process, or system to meet a human need, which may involve technological applications, in addition to scientific knowledge and procedures

simulation

using a model to to study the behaviour of a real or theoretical system

experimental group

the group in the experiment which is exposed to the IV

control group

the group in the experiment which is not exposed to the IV; used as a baseline for comparison

within subjects experimental design

an experimental design in which participants complete every experimental condition

between subjects experimental design

an experimental design in which individuals are divided into different groups and complete only one experimental condition

mixed experimental design

an experimental design which combines elements of within-subjects and between-subjects designs

population

the entire group of research interest from which the sample is drawn

sample

smaller subset of the research population who participate in the study; they are ideally representative of the population

convenience sampling

participants are selected on their availability

random sampling

any technique where the participants in the population have an equal chance of being in a sample

stratified sampling

any technique that divides population into strata before participants are selected to ensure they are proportionately represented in the sample

allocation

the process of assigning participants to experimental conditions or groups; usually random allocation is used

extraneous variable

any variable other than the IV that can change the DV

confounding variable

a variable that has directly and systematically affected the DV, apart from the IV; identified at the end of an experiment

participant-related variables

characteristics of a study's participants that may affect the results

order effects

the tendency for the order in which participants complete experimental conditions to have an effect on their behaviour

placebo effects

when participants react to an inactive substance or treatment as a result of their expectations or beliefs

experimenter effect

when the expectations of the researcher affect the results of an experiment

situational variables

an environmental factor that may affect the DV

non-standardised instructions and procedures

when directions and procedures differ across participants or experimental conditions

demand characteristics

cues in an experiment that may signal to the participant the intention of the study and therefore influence their behaviour

counterbalancing

ordering experimental conditions in a certain way to reduce order effects

single-blind procedure

when participants are unaware of the experimental group or condition they have been allocated to

double-blind procedure

when both participants and the experimenter do not know which condition or group participants are allocated to

primary data

data collected first-hand by a researcher

secondary data

data sourced from others' prior research

quantitative data

data that is expressed numerically

qualitative data

data that is expressed non-numerically

objective data

data that is observed and measured independently of personal opinion

subjective data

data that is informed by personal opinion, perception, or interpretation

mean

a measure of central tendency that describes the numerical average of a data set, expressed as a single value

median

a measure of central tendency that is the middle value in a data set ordered from lowest to highest

mode

a measure of central tendency that is the most frequently occurring value in a data set

outlier

a value that differs significantly from other values in a data set

range

a measure of variability that is a value obtained by subtracting the lowest value in a data set from the highest value

standard deviation

a measure of variability, expressed as a value that describes the spread of data around the mean

accuracy

how close a measurement is to the true value of the quantity being measured

precision

how closely a set of measurement values agree with each other

systematic errors

errors in data that differ from the true value by a consistent amount

random errors

errors in data that are unsystematic and occur due to chance

uncertainty in data

the lack of exact knowledge relating to something being measured due to potential sources of variation in knowledge

repeatability

the extent to which successive measurements produce the same results when carried out under identical conditions

reproducibility

the extent to which successive measurements produce the same results when repeated under different conditions

internal validity

the extent to which an investigation truly measures or investigates what it claims to; not due to any other factors

external validity

the extent to which the results of an investigation can be applied to similar individuals in different settings (generalised)

beneficence

maximising benefits and minimising risks and harms

integrity

searching for knowledge, honestly reporting all sources of information and results, in ways that permit scrutiny

justice

ensuring there is fair consideration of competing claims, no unfair burden placed on a particular group, and fair access to the benefits of research

non-maleficence (do no harm)

the principle of avoiding causing harm

respect

the consideration of the extent to which living things have value, ensuring they are protected and empowered where possible

confidentiality

the privacy, protection and security of a participant's personal information in terms of personal details and the anonymity of individual results

informed consent

ensuring participants understand the nature and purpose of the experiment, including potential risks, before agreeing to participate

deception

intentionally misleading participants about the true nature of a study or procedure

debriefing

informing participants about the true nature, purpose, results and conclusions of the experiment

voluntary participation

ensuring there is no coercion or pressure put on the participant to partake in an experiment, and they freely choose to be involved

withdrawal rights

the right to discontinue involvement in an experiment at any time during, or after the conclusion of an experiment, without penalty