, Volume 15, Issue 1, pp 29–47 | Cite as

A hybrid classification scheme for mining multisource geospatial data

  • Ranga Raju VatsavaiEmail author
  • Budhendra Bhaduri


Supervised learning methods such as Maximum Likelihood (ML) are often used in land cover (thematic) classification of remote sensing imagery. ML classifier relies exclusively on spectral characteristics of thematic classes whose statistical distributions (class conditional probability densities) are often overlapping. The spectral response distributions of thematic classes are dependent on many factors including elevation, soil types, and ecological zones. A second problem with statistical classifiers is the requirement of the large number of accurate training samples (10 to 30 × |dimensions|), which are often costly and time consuming to acquire over large geographic regions. With the increasing availability of geospatial databases, it is possible to exploit the knowledge derived from these ancillary datasets to improve classification accuracies even when the class distributions are highly overlapping. Likewise newer semi-supervised techniques can be adopted to improve the parameter estimates of the statistical model by utilizing a large number of easily available unlabeled training samples. Unfortunately, there is no convenient multivariate statistical model that can be employed for multisource geospatial databases. In this paper we present a hybrid semi-supervised learning algorithm that effectively exploits freely available unlabeled training samples from multispectral remote sensing images and also incorporates ancillary geospatial databases. We have conducted several experiments on Landsat satellite image datasets, and our new hybrid approach shows over 24% to 36% improvement in overall classification accuracy over conventional classification schemes.


MLC EM Semi-supervised learning 



We would like to thank our collaborators Prof. Shekhar and Prof. Thomas E. Burk at the University of Minnesota for their contributions and support. We would like to thank ORNL reviewers Eddie Bright, Phil Coleman, Veeraraghavan Vijayaraj, and the unanimous SSTDM-07 workshop reviewers whose comments have greatly helped us in improving the technical quality of this paper. This research was partially supported by the LDRD initiative on “Emerging Science and Technology for Sustainable Bioenergy.”


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Copyright information

© US Government 2010

Authors and Affiliations

  1. 1.Computational Sciences and Engineering DivisionOak Ridge National LaboratoryOak RidgeUSA

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