Correlations

• Correlational techniques 


  non-experimental methods used to measure how strong the relationship is between two or more variables. In an experiment the effect of an independent variable upon the dependant variable is measured however in correlational studies the movement and direction of co variables in response to each other is measured. There is no claim of a cause and effect relationship, although after a correlational study has been conducted, further research will often be conducted to determine if one variable is in fact affecting the other.
• Positive correlation


  As one variable increases the other variable increases
• negative correlation 


  as one variable increases the other variable decreases
• zero correlation 


  occurs when a correlational study finds no relationship between variables
• Correlation coefficient 


  used to measure the strength and nature of the relationship between two co variables. the correlation coefficient number represents the strength of the relationship and can range between -1.0 and +1.0. A perfect positive correlation has a correlation coefficient of +1 and for a perfect negative correlation it is -1
• Scattergram


  A graph that shows the correlation between two sets of data by plotting points to represent each pair of scores. It indicates the degree and direction of the correlation between the co-variables, one of which is indicated on the X-axis and the other on the Y-axis