correlations AO1

Question 1

explain what correlations are
- where are the plotted?

Answer 1

• correlations illustrates the strength and direction of an association between two or more co-variables (things that are being measured).
• correlations are plotted on a scattergram - one co-variable is plotted on the x-axis and the other on the y-axis
• each point or dot on the graph is the x and y position of each co-variable.

Question 2

what are the different types of correlations?
- explain what they are

Answer 2

• positive correlation e.g. it means the more the more caffeine people drink, the higher their level of anxiety. As one co-variable increases, so does the other
• negative correlation: as one variable rises, the other falls
• Zero correlation: there is no relationship between each variable e.g. number of caffeine drinks someone has and the number of dogs they see in the street

Question 3

what is the difference between correlations and experiments

Answer 3

• in an experiment, the researcher controls or manipulates the independent variable (IV) in order to measure the effect on the dependant variable (DV). A a result of this deliberate change in one variable it is possible to infer that the IV caused any observed changes in the DV
• In contrast, in correlations, there is no such manipulation of one variable and therefore it is not possible to establish cause and effect between one co-variable and another. Even if we found a strong positive correlation between caffeine and anxiety level we cannot assume that caffeine was the cause of the anxiety.