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A comparison of minimum distance and maximum likelihood techniques for proportion estimationThe estimation of mixing proportions P sub 1, P sub 2,...P sub m in the mixture density f(x) = the sum of the series P sub i F sub i(X) with i = 1 to M is often encountered in agricultural remote sensing problems in which case the p sub i's usually represent crop proportions. In these remote sensing applications, component densities f sub i(x) have typically been assumed to be normally distributed, and parameter estimation has been accomplished using maximum likelihood (ML) techniques. Minimum distance (MD) estimation is examined as an alternative to ML where, in this investigation, both procedures are based upon normal components. Results indicate that ML techniques are superior to MD when component distributions actually are normal, while MD estimation provides better estimates than ML under symmetric departures from normality. When component distributions are not symmetric, however, it is seen that neither of these normal based techniques provides satisfactory results.
Document ID
19830026124
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Woodward, W. A.
(Southern Methodist Univ. Dallas, TX, United States)
Schucany, W. R.
(Southern Methodist Univ. Dallas, TX, United States)
Lindsey, H.
(Southern Methodist Univ. Dallas, TX, United States)
Gray, H. L.
(Southern Methodist Univ. Dallas, TX, United States)
Date Acquired
September 4, 2013
Publication Date
November 1, 1982
Subject Category
Earth Resources And Remote Sensing
Report/Patent Number
NASA-CR-171678
SR-62-04376
NAS 1.26:171678
E83-10402
Accession Number
83N34395
Funding Number(s)
PROJECT: PROJ. AGRISTARS
CONTRACT_GRANT: NAS9-16438
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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