PEDOMODELS FITTING WITH FUZZY LEAST SQUARES REGRESSION

Document Type: Research Paper

Authors

1 SOIL SCIENCE DEPARTMENT, COLLEGE OF AGRICULTURE, SHAHREKORD UNIVERSITY, SHAHREKORD, IRAN.

2 SCHOOL OF MATHEMATICAL SCIENCES, ISFAHAN, UNIVERSITY OF TECHNOLOGY, ISFAHAN 84156, IRAN.

Abstract

Pedomodels have become a popular topic in soil science and environmental
research. They are predictive functions of certain soil properties based on other easily or
cheaply measured properties. The common method for fitting pedomodels is to use classical
regression analysis, based on the assumptions of data crispness and deterministic relations
among variables. In modeling natural systems such as soil system, in which the above
assumptions are not held true, prediction is influential and we must therefore attempt to
analyze the behavior and structure of such systems more realistically. In this paper we
consider fuzzy least squares regression as a means of fitting pedomodels. The theoretical and
practical considerations are illustrated by developing some examples of real pedomodels.

Keywords


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