information class definition
information class means a class which is directly of informational value to user according to the specific purpose of data analysis. If the purpose is for finding classes of objects on ground via remotely sensed data, then, the list of information classes might include the names of objects on the ground, specific plant species. If it is for detecting a particular target, then, the information classes could be {target, non-target}. Since information classes are defined ordinarily based solely on the user's interests, they may not be separable in the feature space. Thus, in the classifier training stage, the given data sets might be analyzed, for example, through a clustering, to find a mutually exclusive and exhaustive set of sub-classes or "data classes" each of which can be modeled by an appropriate probability density function. Due to the computational complexity and a practical limitation on the requirement for training samples etc., the data sets are assumed, in general, to be class-conditionally independent of each other (see (Lee et 87) for a discussions of this assumption), and each data set is separately analyzed in the training stage. Therefore different data sets can have