Correlational studies Flashcards
What’s correlation?
A correlation is a relationship between two variables
What’s a correlational study?
test between variables
and to see if related and if so how strong and if their co variables
When do we use a correlational design?
To test realtionship between 2 variables
e.g. age and reaction time
How to use correlation?
1-decide what co variables were measuring and operationalise them
2- measure p’s on bith covariants
3-plot variables on scatter graphs to see relationship
4-carry out test to see if relationships significant or chance producing a correlation coefficient
What’s a positive correlation? and example
When one variable increases another increases
The taller a person is the heavier they are
what’s the coefficient of a positive correlation?
0- +1
Diagram of positive correlation?
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What’s a negative correlation and example?
As one variable increases the other decreases
The more alcohol you drink the less you can remember
What’s the coefficient of a negative correlation?
0 to -1
Graph of a negative correlation
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What is no correlation and example?
Theirs no relationship between variables
Shoe size and iq
what’s no correlation coefficient
close to 0
No correlation graph?
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The higher the number?
The stronger the coefficient
What’s a correlation hypothesis?
The hypothesis will state realtionship between 2 co variables
Non directional- there will be a correlation
Directional- their will be a pos/neg correlation
Null- their will be no significant correlation
