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Scattergrams can tell you the strength of the relationship between the two variables.
* If the dots cluster close to an imaginary line, there is a very strong relationship or correlation between the two variables.
* When the dots are scattered in an ellipse or cigar-shape, there is a moderate correlation.
* When the dots are scattered randomly around the graph, there is a low or negligible correlation.
Scattergrams can tell us the direction of the relationship between the two variables.
* If the slope of the line falls from left to right, there is a negative correlation.
* If the slope of the line rises from left to right, there is a positive correlation.
Scattergrams form the shape of a cigar if there is a positive or negative strong correlation between the two variables you are studying. The further away from an elliptical shape, the weaker the correlation. It is a quick snapshot picture of the relationship between the two variables.
Return from scattergram to statistical tests.