Correlations

Cards (12)

What is a correlation?
Shows the strength and direction of an association between 2 or more co-variables (things being measured)
what are correlations plotted on?
scattergram
what is a positive correlation
an increase in one variable is accompanied by an increase in another variable
what is a negative correlation?
one variable increases and the other decreases
why does a correlation not mean causation?
cannot establish cause and effect relationship
there is no manipulation of one variable
what is an intervening variable?
factors that influence the relationship between 2 other variables
what correlation co-efficient shows perfect positive correlation?
+1
what correlation co-efficient shows a perfect negative correlation?
-1
what correlation co-efficient shows now correlation?
0
what are the strengths to correlations?
precise and measurable
often used as a starting point before committing to full studies
secondary date can be used which is quicker and more economical
What are limitations to correlations?
Only tells us how variables are related but not why
third variable problem
often misused and misinterpreted
What is a third variable problem?
Another untested variable is causing the relationship between the 2 co-variables