Research Methods Definitions

aim

indication of why the study is taking place

coding

categorising qualitative data

content analysis

method for changing qualitative data into quantitative data

continuous data

there are no gaps between the measurements

correlational analysis

this shows the strength of a relationship between two variables

counter-balancing

half the participants do Task A followed by Task B and the other half do Task B followed by Task A (to cancel out order effects)

demand characteristics

the participants guess the purpose of the experiment and change their behaviour

discrete data

there are gaps between the data

double blind

neither the participants nor the investigator know the purpose of the study

hypothesis

a testable statement which predicts what might happen

ecological validity

the experiment is like a real-life setting

experimental condition

situation imposed on the participant by the experimenter

independent groups design

different participants are used in each of the conditions

directional hypothesis

a testable statement which predicts whether the independent variable will improve or not the dependent variable

internal validity

the independent variable caused the dependent variable

interval data

the data is ordered with equal intervals between the measurements

interviews

the experimenter asks questions face-to-face

investigator effects

the effect the investigator has on the participants based on appearance, accent, personality, etc

volunteer sampling

the participants volunteer

validity

does the experiment measure what it is supposed to measure

unstructured interviews

the topic is predetermined but the questions are not

test-retest reliability

the experiment is run again so results can be compared. if there is reliability then the results will be consistent

structured interviews

the questions are pre-set

standard deviation

variance from the mean

skewed data

data with anomylies

single blind study

the participants do not know the purpose of the study

sampling

the selection of participants

replication

repeating an experiment to check reliability

repeated measures

the same participants take part in all conditions

reliability

consistency

rapport

good relationship between experiment and participant

range

the difference between the highest and lowest score

questionnaire

a pre-set list of questions

quantitative data

numerical data

random sampling

every member of the target population has an equal change of being selected

qualitative data

deals with experiences, description

positive correlation

as one variable increases, so does the other

placebo

substance or treatment of no known value used on a control group

placebo effect

the improvement demonstrated in the control group due to the administration of a treatment of no known value

pilot study

small scale study beforehand to check the equipment, techniques and feasibility

mean

arithmetic average

parametric statistics

these assume that the population in the research sample falls in a normal distribution

opportunistic sampling

selection of participants from those who are easily available

ordinal data

the data is ordered

operationalise

variables are operationalised to indicate the measurement used

order effects

these occur when the first task influences the second task

null hypothesis

this predicts that any results from the experiment occured by chance

nominal data

observations are put into named categories

non-directional hypothesis

predicts whether the independent variable will influence the dependent variable

mode

the most frequently occurring number in the data

negative correlation

as one variable increases the other decreases

median

the middle score

measures of dispersion

range and standard deviation

measure of central tendency

mean, median and mode

matched pair design

different participants with similar traits are compared across two conditions

laboratory experiment

takes place in a controlled environment