Chapter 3 Measuring and manipulating variables (Terminology associated…
Chapter 3 Measuring and manipulating variables
Difference between correlational and experimental research
Methods answer different kinds of questions
Establishing links, systematically and frequently.
Links between 2 variables
Not always possible to know the direction of effect
Possibly linked to a third factor
Caution is required when explaining results - 3 rd factor and direction of effect needs to be considered. Cannot draw a conclusion that one thing caused another thing.
Establish causal links between variables
Both need to address if it is ethical and if there is a good indication that research is required
Terminology associated with experiments and experimental design
Variables in an experiment
Variations of the independent variable
Can be manipulated
Baseline condition, against which experimental conditions can be compared
Not always possible. For example when manipulating gender age etc.
A variable that is expected to change as a result of manipulation of IV
A variable which is not controlled by the researcher
WITHIN- PARTICIPANTS DESIGN- ALSO REFERRED AS THE REPEATED MEASURES DESIGN
When participants take part in all conditions of the experiment- tested more than once
Can rule out individual differences as a confounding variable for example
Some points to consider
if completion of one condition will influence performance in another condition? I.e will the participant gain practice?
Will they become overloaded and do worse?
Will they get bored?
BETWEEN PARTICIPANTS DESIGN OR INDEPENDENT GROUPS DESIGN
Take part in only one condition
Refers to when participants are randomly assigned to different conditions
Personal attributes that may influence the results are evenly spread across the conditions
Not possible if IV is gender, age - naturally occurring difference
Feature of Between- participants design
MATCHED PARTICIPANTS DESIGN
Matched according to features crucial for the experiment. I.e Brain injury studies -P100
An aspect of experimental design that includes all possible orders in which participants complete tasks or conditions, or in which experimenters present stimuli - this is to control for 'order of effects'
The influence that performing one task may have on performing another task
The extent to which a study reflects naturally occuring or everyday situations
Analysing content of written material or audio -visual material, and coding this in terms of pre selected features
Feautures of the method section
Info about age and gender are routinely provided
Design (sometimes featured describing the IV and DVs)
Merits of method of researching the impact of TV on children
Content analysis as a research method means you do not need to recruit participants
Useful for providing estimates