Weighted Average Method for Land Grading Design
Publication: Journal of Irrigation and Drainage Engineering
Volume 130, Issue 3
Abstract
Based on the theory of the least squares and the statistical properties of the best statistic with an unbiased estimate and minimum variance, a new method for land grading design is presented. Although it is based on least-squares theory, it does not have the cumbersome and time consuming calculations of the terms of the simultaneous equations that appear in the conventional least-squares method. In rectangular fields, the method is as accurate as the conventional least-squares method. In irregularly shaped fields the results are different but the differences are negligible. Since the developed equations can be solved by using a calculator in statistical mode and a readily available table, the proposed method has the advantage of being amenable to hand calculation.
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Information
Published In
Journal of Irrigation and Drainage Engineering
Volume 130 • Issue 3 • June 2004
Pages: 239 - 247
Copyright
Copyright © 2004 American Society of Civil Engineers.
History
Received: Sep 11, 2002
Accepted: Jul 30, 2003
Published online: May 14, 2004
Published in print: Jun 2004
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