Experimental Method Flashcards
Aim
-A general statement of what someone intends to achieve.
What is a hypothesis
A statement of what the researcher believes to be true
(Prediction)
Operationalisation
-Clearly defining something in terms of how it can be measured
Independent variable
-Variable that is changed
Dependent variable
The variable that is measured
Directional hypothesis (two tailed)
States that there will be a change and the direction in which the results are expected to go
Non directional hypothesis (one tailed)
-States that there will be a change but not the direction in which the results are expected to go
Extraneous variable
-‘nuisance variables’
- variable other than the independent variable (IV) that could affect the dependent variable (DV) in an experiment, if not controlled (makes difficult to establish C+E)
Confounding variable
-A variable that systematically influences both the independent variable (IV) and the dependent variable (DV), making it difficult to determine whether changes in the DV are due to the IV or the confounding variable.
Demand characteristics
-Any cue from the researcher or research situation that may reveal the aim of the study, leading to the participant changing their behaviour, affecting the reliability of the results
Investigator effects
-Any effect of the investigators behaviour on the outcome of the research (DV), intentional or not.
Situational variables
-The environment or setting of an experiment that could affect the dependent variable (DV), if not controlled
Participants variables
-A type of extraneous variable related to individual differences between participants that could affect the dependent variable (DV) in a study.
Randomisation
-The use of chance when designing investigations to control the effects of bias and EV’s
E.G allocating participants to conditions
Standardisation
-Using the exact same procedures and instructions for all particpants in an experiment. This controls EVS
Pilot studies
-Small scale trial run of an investigation to ‘road test’ procedures so that research design can be modified
Control groups
-Used to set a comparison to other conditions in a study.
They act as a ‘baseline; and help to establish causation
Single blind studies
-A participant doesn’t know the aims of the study, but researcher does. This helps to reduce demand characteristics. (Increase internal validity)
Double blind studies
-Both researchers and participants don’t know aims of the study, reducing demand characteristics and investigator effects
Name 4 EVS
-Demand characteristics
-Investigator effects
-Participant variables
-Situational variables
External validity /mundane realism
-How well an experiment mirrors the real world
Internal validity
-Whether the effects of the experiment are down to the manipulation of the IV or some other extraneous variable
Validity
-Does the study measure what it intended to measure?
Reliability
-How consistent the findings from an experiment are (need to be able to replicate and standardise it)
