ABSTRACT

Many experiments consist of changing the value of a factor (the independent variable, the predictor) and measuring the response (the dependent variable, the outcome). This produces many pairs of data points. It is often convenient to present these in graphical form, and it is conventional to plot the factor on the X axis (the abscissa) and the response on the Y axis (the ordinate). The independent variable, for example, time and concentration, is chosen by the experimenter and should be subject to negligible error. The response is subject to random error associated with measurement.