PLANT-GROWTH ANALYSIS - A PROGRAM FOR THE FITTING OF LENGTHY SERIES OF DATA BY THE METHOD OF B-SPLINES

A method is presented for fitting curves to lengthy and/or complicated series of data on plant growth. A computer program which derives the usual plant growth analytical quantities, and their errors, from these fitted curves is also described and offered for circulation. The fitted curves are splined cubic polynomial exponentials. Examples of their application are given, employing both real and artificial data. In any set of data the number of splines, and the position of the knots joining them, may be determined either by objective statistical tests or by the experimenter, who retains a considerable degree of control over the process but can call on the assistance of the program if required. The value of this method is considered in relation to other curve-fitting approaches to plant growth analysis. Provided sufficient primary data are available, the method is free from many of the problems which beset earlier work in this field.