"The measure of how strongly two or more variables are related to each other"
There are 3 correlations which can occur -
1. POSITIVE CORRELATION
3. NO CORRELATION
"high values of one variable are associated with high values of the other...the variables increase together"
X: the number of hours a child spends on watching violent TV shows
Y: the aggressiveness of a child
The more time a child spends on watching violent TV show, the more aggressive is the child.
"high values of one variable are associated with low variables of the other...as one variable increases the other decreases"
still indicates some relationship exsist
Example X: the number of hours a student spends on watching TV
Y: a student’s mark on the exam
The more time a student spends on watching TV, the lower his/her mark is on the exam.
"If there is no correlation between two variables they are said to be uncorrelated"
NOTE THAT A HYPOTHESIS FOR CORRELATION IS A PREDICTION OF A RELATIONSHIP AND NOT A DIFFERENCE OR CAUSE AND EFFECT.
Therefore you should never write a hypothesis for a correlation that includes the words 'DIFFERENCE', 'CAUSE' or 'EFFECT'.
EVALUATION OF CORRELATINAL ANALYSIS
+They are very good for showing possible relationships between variables. Researchers may often use correlation analysis as a starting point in their research and if a relationship is found between variables they can then investigate this further.
-They cannot demonstrate cause and effect relationshi between variables.