correlations

Question 1

correlation

Answer 1

this illustrates the strength and direction of an association between co-variables

Question 2

co-variables

Answer 2

the variables investigated within a correlation

Question 3

positive correlation

Answer 3

as one co-variable increases, so does the other / as one co-variable decreases so does the other

Question 4

negative correlation

Answer 4

as one co-variable increases, the other co-variable decreases

Question 5

zero correlation

Answer 5

when there is no relationship between the co-variables

Question 6

useful preliminary tool

Answer 6

correlations are a useful preliminary tool for research, if variables are strongly related a researcher may then commit to an experimental study

Question 7

cant establish cause and effect

Answer 7

correlations cant establish cause and effect between variables as there is no manipulation and their may be a third untested variable that causes the relationship

Question 8

difference between experiments and correlations

Answer 8

in an experiment, the researcher manipulates the IV and records the effect on the DV, in a correlation there is no manipulation and so cause and effect cannot be demonstrated. In a correlation, the influence of the EV is not controlled, so it may be a third ‘untested’ variable causing the relationship between the co-variables. Higher level of control in experiments.

Question 9

correlation significance is analysed using statistical tests

Answer 9

these tests produce a numerical value between -1 and +1, this is the correlation coefficient

correlation coefficient represents the direction and strength of the relationship between two co-variables

the closer the coefficient is to 1 the stronger the relationship between the co-variables is
the closer the coefficient is to 0 the weaker the relationship is

r=1 is a perfect correlation
r=.9 .8 .7 is a strong correlation
r= .6 .5 .4 is a moderate correlation
r= .3 .2 .1 is a weak correlation
r= 0 is zero correlation