Correlational Design

Correlational Design

1. Correlational Analysis = An investigation that measures the extent of the relationship between two co-variables.

   • Positive correlation - the co-variables increase or decrease together
   • Negative correlation - one variable increases while the other decreases
   • No correlation - there is no relationship between the two variables

2. Correlation coeffiencent

   • A number that tells us how closely the co-variables in a correlation analysis are related. The stronger the correlation the nearer the correlation coefficient is to +1 or –1. If the correlation coefficient has a minus sign before it this means that it is a negative correlation, otherwise it is a positive correlation.

3. Evaluation

   • Correlations allow researchers to investigate situations that couldn't be done experimentally - they are used when it is practically or ethically impossible to manipulate the IV
   • Preliminary Research - conducting preliminary research as correlation studies can indicate trends which may lead to further research using experimental means to establish causal links. They are a useful and simple way of starting off a research project and can help to prevent time being wasted in carrying out unrealistic experiments.
   • Cannot establish cause and effect – correlations can only tell us how variables are related but not why, meaning we do not know which co-variable is causing the other to change.
   • Third Variable Problem - there may be other unknown variables that can explain why the co-variables being studied are linked.