scholarly journals Research on Building Methods of Hierarchical Structure in Text Classification

2012 ◽  
Vol 6-7 ◽  
pp. 742-747
Author(s):  
Yun Bo Xiong

There always exists semantic hierarchical relationship in text classification. Therefore, it's inevitable to organize documents in accordance with the hierarchical structure. Based on confusion matrix, this paper attempted to adopt two different algorithms including hierarchical clustering and confusion category to build hierarchical structure of document category, and finally made use of hierarchical classification to carry on experiment, results of which showed that the confusion category strategy is superior to hierarchical clustering strategy and recall and precision of flat classification are both improved.

AI Magazine ◽  
2019 ◽  
Vol 40 (2) ◽  
pp. 59-65
Author(s):  
Denali Molitor ◽  
Deanna Needell

In classification problems, especially those that categorize data into a large number of classes, the classes often naturally follow a hierarchical structure. That is, some classes are likely to share similar structures and features. Those characteristics can be captured by considering a hierarchical relationship among the class labels. Motivated by a recent simple classification approach on binary data, we propose a variant that is tailored to efficient classification of hierarchical data. In certain settings, specifically, when some classes are significantly easier to identify than others, we show case computational and accuracy advantages.


Author(s):  
A. K. Cherkashin ◽  

A hierarchical system is the result of dividing a set of objects into subordinate groups in order from highest to lowest, where each lower level reveals and clarifies the properties of objects at a higher level. There is a difference between the natural hierarchy of geosystems-geochors and the hierarchy of geomers, which leads to taxonomic classification. Theoretical basis for creating a hierarchical classification of geosystems are developed using a conceptual model of geographical cycles of accumulation and removal of factor load on territorial objects of various scales. The cone of chorological and typological connections is considered as the basic metamodel of hierarchical structure. For its research, we use descriptive geometry tools to represent the cone in the vertical and horizontal (plan) projections. The surface and unfolding structures of the cone with sections at different levels reflect the hierarchy. The planned projection in the form of concentric structures is considered as model of the archetype of hierarchy formation. The horological and typological classifications converge in the position “natural zone” as the “parent core” of the type of natural environment, which represents the zonal norm. The concentric model has various interpretations, in particular, it is described as a system of local coordinates, where each coordinate corresponds to the categories of seriality of geosystems, i.e. the degree of their factoral-dynamic variability relatively to zonal geosystems. In the coordinate approach, the classification looks like a ranked set of merons and taxa, where the meron categories are represented by quantum numbers of the coordinate series, and the taxon is a sequence of such numbers of different series (numeric code). The formation of hierarchical classification is based on the triad principle, when the taxon of the upper level is divided into three lower level gradations, which are arranged in a homological series according to the degree of seriality. There is an analogy between the hierarchical structure of the periodic system of chemical elements and the typological classification of geosystems, when the periods of the system of elements correspond to the high-altitude layers and latitudinal zones of geochor placement or hierarchical levels of geomer classification. An unfolding and plan projection of the classification cone of facies for the Prichunsky landscape of the southern taiga of Central Siberia in three basic categories of variability of different levels geomers are presented.


2011 ◽  
Vol 255-260 ◽  
pp. 2233-2237
Author(s):  
Xiao Yun Chen ◽  
Jin Hua Chen

There is a problem that the difficulty in text classification will increase when the number of classes increases, to which hierarchical structure is a viable solution. Well, a document’s hierarchical structure is usually maintained only by hand, which require substantial manpower to find the correct position of a document in the class hierarchy or to reconstruct the hierarchy. Constructing the hierarchical structure automatically by clustering the training samples can effectively reduce the cost of manual maintenance, and at the same time, it can avoid the conflict between the prior knowledge and the statistical properties of the sample set caused by artificial maintenance of the hierarchy.


Author(s):  
Janusz Adam Frykowski

AbstractThe following paper depicts the history of Saint Simeon Stylites Uniate Parish in Rachanie since it became known in historical sources until 1811- that is the time it ceased to be an independent church unit. The introduction of the article contains the geographical location of the parish, its size and the position within the hierarchical structure of the Church. Having analysed post-visit inspection protocols left by Chelm Bishops, the appearance as well as fittings and ancillary equipment of the church in Rachanie in that particular period are reported. Moreover, the list of 4 local clergymen is recreated and their benefice is determined. As far as possible, both the number of worshipers and the number of Holy Communion receivers is determined.


1993 ◽  
Vol 18 (2-4) ◽  
pp. 129-149
Author(s):  
Serge Garlatti

Representation systems based on inheritance networks are founded on the hierarchical structure of knowledge. Such representation is composed of a set of objects and a set of is-a links between nodes. Objects are generally defined by means of a set of properties. An inheritance mechanism enables us to share properties across the hierarchy, called an inheritance graph. It is often difficult, even impossible to define classes by means of a set of necessary and sufficient conditions. For this reason, exceptions must be allowed and they induce nonmonotonic reasoning. Many researchers have used default logic to give them formal semantics and to define sound inferences. In this paper, we propose a survey of the different models of nonmonotonic inheritance systems by means of default logic. A comparison between default theories and inheritance mechanisms is made. In conclusion, the ability of default logic to take some inheritance mechanisms into account is discussed.


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