I displayed these d values on the graph for you. Notice that they are the vertical distance from the real data points to the fitting linear function. Why this way?

Linear equations can be shown on a graph. Find out how to create one in this Bitesize KS3 maths video.

Ever wonder what sorts of errors freshman math students make? There are a couple of pretty basic ones.

Journal of the Royal Statistical Society. Series C (Applied Statistics), Vol. 30, No. 2 (1981), pp. 125-131 (7 pages) In generalized linear models each observation is linked with a predicted value ...