Positive and Negative Correlation

What is correlation?

Correlation looks at the strength of a relationship between two variables

What is an independent variable?

The factor that causes the dependent variable to change

What is a dependent variable?

The variables that are influenced by the independent variable

How should you explain a scatter graph?

• Correlation is usually measured by using a scatter diagram, on which data points are plotted

• The dependent variable is normally plotted on the y-axis: and the independent variable is on the x-axis

• A ‘line of best fit’ (the regression line) attempts to plot the mathematical relationship between the variables based on the data points

What is a positive correlation?

A positive relationship exists whereas the independent variable increases in values, so does the dependent variable

What is negative correlation?

A negative relationship exists whereas the independent variable increases in value, the dependent variable falls in value

What is no correlation?

There is no discernible relationship between the independent and dependent variable

What indicates the strength of the correlation?

The line of best fit

What is a strong correlation?

It means that there is little room between the data points and the line of best fit

What is a strong correlation?

It means that the data points are spread quite wide and far from the line of best fit

What happens if the data suggests a strong correlation?

The relationship might be used to make marketing predictions