On the Systematic Fitting of Straight Line Trends by Stencil and Calculating Machine
Whenever there is only one plotting point corresponding to IV successive abscissal values equally spaced, it is possible greatly to simplify the fitting of straight lines to the empirical observations. Let the N several absicissal values (ordinarily time) be X % , X2 1 X3, Let these several % values be replaced by a series of transmuted steps.. X. ( ?, 3, -} a)1 Let the several corresponding ordinates be y,, y., y3). . The situation is represented in Figure 1.