Key words Flashcards
Variable
Any factor that can vary or change within an investigation. They are generally used in experiments to determine if changes in one factor result in changes to another
Independent variable
Some aspect of the experimental situation that is manipulated (changed) by the researcher, or changes naturally, so the effect on the dependent variable can be measured
Dependent variable
The variable that is measured by the researcher. Any effect on the dependent variable should be caused by the change in the independent variable
Aim
A general statement of what the researcher intends to investigate (the purpose of the study). It is stated at the outset of the study.
Experimental group/condition
The group/condition in the experiment that received the experimental treatment (the independent variable)
Control group/condition
The group/condition in the experiment that receives no treatment (they are the baseline)
Operationalisation
Clearly specifying/defining observable behaviours that represent the more general construct under investigation/to enable the behaviour under investigation to be measured. In simple terms, this means clearly defining variables in terms of how they can be measured
Extraneous variable
Any variable, other than the independent variable that may affect the dependent variable if it is not controlled.
Confounding variable
A kind of extraneous variable but the key feature is that a confounding variable varies systematically with the independent variable. Therefore, we can’t tell if any change in the dependent variable is due to the independent variable or the confounding variable.
Demand characteristics
Any cue from the researcher or from the research situation that may be interpreted by participants as revealing the purpose of an investigation. This may lead to a participant changing their behaviour within the research situation.
Investigator effects
Any effect of the investigator’s behaviour (conscious or unconscious) on the research outcome (the DV). This may include everything from the design of the study to the selection of and interaction with participants during the research process.
Participant variables
Characteristics of individual participants (such as age, intelligence, etc.) that might influence the outcome of a study.
Situational variables
Features of the environment which may influence the outcome of a study (e.g., noise, temperature)
Social desirability bias
A tendency for respondents to answer questions in such a way that presents themselves in a better light.
Randomisation
The use of chance methods to control for the effects of bias when designing materials and deciding the order of conditions. Controls participant variables
Standardisation
Using exactly the same formalised procedures and instructions for all participants in a research study so as to avoid investigator effects caused by different procedures/instructions.
Single-blind design
A type of research design in which a participant is not aware of research aims and/or of which condition of the experiment they are receiving. Controls demand characteristics
Double-blind design
Neither the participant nor the researcher conducting the study are aware of the research aims or other important details of a study, and thus have no expectations that might alter a participant’s behaviour. Controls demand characteristics and investigators effect
Experimental method
A research process that involves following scientific guidelines to test hypotheses and establish causal relationships between variables (that the IV is manipulated and this is what causes the changes in the DV). There are three important requirements of scientific research that follow the experimental method; these are that research should be empirical, reliable and valid.
Laboratory experiment
An experiment that takes place in a controlled environment within which the researcher manipulates the IV and records the effect on the DV, whilst maintaining strict control of extraneous variables.
Field experiment
An experiment that takes place in a natural setting within which the researcher manipulates the IV and records the effect on the DV.
Natural experiment
An experiment where the change in the IV is not brought about by the researcher but would have happened even if the researcher had not been there. The researcher records the effect on a DV they have decided on.
Quasi-experiment
A study that is almost an experiment but lacks key ingredients. The IV has not been determined by anyone (the researcher or any other person) - the “variables” simply exist, such as being old or young. Strictly speaking this is not an experiment - the IV is a naturally occurring difference between participants
Experimental designs
The different ways in which the participants are assigned to different groups/conditions of the experiment – independent groups, repeated measures or matched pairs
Independent groups
Participants are allocated to different groups where each group represents one experimental condition
Matched pairs
Pairs of participants are first matched on some variables that may affect the dependent variable. Then one member of the pair is assigned to Condition A and the other Condition B
Repeated measures
All participants take part in all conditions of the experiment
Random allocation
An attempt to control for participant variables in an independent groups design which ensures that each participant has the same chance of being in one condition as any other