Direction of the relationship

The relationship between two variables can be in one or two directions-positive and negative. If there is no clear relationship, a line of best fit won’t be possible.

The strength of relationship shows how closely two variables are linked. A strong relationship would have most of data point close to the line of best fit. A weak relationship shows a relationship of two variables, but the data point shows more variable. As well as be positive or negative, the relationship between variables can be described as linear or non-linear. If the relationship is non-linear the line of best fit would not be a straight line

Sometimes some points are quite different from other points in the scatter plot. These points are called outliers. A decision is needing to be made to whether keep the outlier in the analysis, or the outlier should be ignored.