Use of the Boundary Line in the analysis of biological data

SUMMARYA new approach to the study of crop productivity has been developed in which the performance of the best in the sample examined is taken as a standard against which to judge the remainder, on the assumption that there are reasons other than chance which account for the inferior performance of part of the population.The line defining the best performance in the population lies at the edge of any body of data, hence the name 'Boundary Line', and occurs wherever a cause-and- effect relationship exists between two variables. When the best performance can be quantified, the overall deficiency in yield due to inferior performance can be assessed and the magnitude of the shortfall used in deciding if investigations to increase yield are justified. When it is allied to a knowledge of the components of yield, the position of the Boundary Line can be used to direct attention to phases of growth most likely to respond to better management.