scatter diagrams

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scatter diagrams Sometimes referred to as ‘scattergrams’, these are two-dimensional representations of the relationship between pairs of variables, achieved by plotting each individual case on a graph—as in the hypothetical example shown below. The diagram thus represents the points at which the two variables intersect for each case in the sample. These diagrams can be routinely produced by most statistical computer packages. They allow easy and visual representation of three aspects of a pairwise relationship: whether or not it is linear; whether it is positive or negative; and the strength of the association. They can be useful aids to the understanding of the idea of correlation but are rarely reproduced in the published results of sociological analyses.