Knowledge induction

Knowledge Induction describes the generation of knowledge either directly (com-municaton), indirectly (via information), or through self-inducting (by training). 

Reichel, U. Improving Data Driven Part-of-Speech Tagging by Morphologic Knowledge Induction. Proc. Advances in Speech Technology AST (2005). 

Reichel, U. Improving data driven part-of-speech tagging by morphologic knowledge induction. In Proceedings of Advances in Speech Technology (2005). 

All expert systems depend on expert elicitation and two main approaches are used. Firstly, based on the assumption that experts can articulate their knowledge, a programme of interviewing is carried out. This approach is prone to error as experts are often better at doing than analysing why. The second approach, knowledge induction, relies on second party analysis of case studies that the expert has worked on and is often preferred. 

However, this process of inductive learning is still not over we arc still far away from understanding and predicting all chemical phenomena. This is most vividly illustrated by our poor knowledge of the tindcsircd side effects of compounds, such as toxicity. Wc still have to strive to increase our knowledge of chemistry,... 

Inductive learning has been the major process of acquiring chemical knowledge from the very beginnings of chemistry - or, to make the point, alchemy. Chemists have done experiments, have made measurements on the properties of their compounds, have treated them with other compounds to study their reactions, and have run reactions to make new compounds. Systematic variations in the structure of compounds, or in reaction conditions, provided results that were ordered by developing models. These models then allowed predictions to be made. 

In the endeavor to deepen understanding of chemistry, many an experiment has been performed, and many data have been accumulated. Chapter 6, on databases, gives a vivid picture of the enormous amount of data that have been determined and made accessible. The task is then to derive knowledge from these data by inductive learning. In this context we have to define the terms, data, information, and knowledge, and we do so in a generally accepted manner. 

In the case of chemoinformatics this process of abstraction will be performed mostly to gain knowledge about the properties of compounds. Physical, chemical, or biological data of compounds will be associated with each other or with data on the structure of a compound. These pieces of information wQl then be analyzed by inductive learning methods to obtain a model that allows one to make predictions. 

Now, chemists have acquired much of their knowledge on chemical reactions by inductive learning from a large set of individual reaction instances. How has this been done And how can we build on these methods and knowledge and perform it in a more systematic manner by algorithmic techniques ... 

Thus, when a large set of chemical reactions has to be investigated, an inductive learning process, deriving knowledge on chemical reactions and reactivity from a series of reactions, still has many merits. Such chemical knowledge can be put into models that then allow one to predict the course of new reactions. 

On top of that, reaction databases can also be used to derive knowledge on chemical reactions which can then be used for reaction prediction, The huge amount of information in reaction databases can be processed by inductive learning methods in order to condense these individual pieces of information into essential features... 

One of the first attempts to build a knowledge base for synthetic organic reactions was made by Gelernter s group, through inductive and deductive machine learning [1]. Important work on this topic was also performed by Funatsu and his group [2]. 

The knowledge base is essentially two-fold on one hand it consists of a series of procedures for calculating all-important physicochemical effects such as heats of reaction, bond dissociation energies, charge distribution, inductive, resonance, and polarizability effects (.see Section 7.1). The other part of the knowledge base defines the reaction types on which the EROS system can work. 

Chemical analysis of composite systems is often severely restricted by the invalidity of the co-existence principle (although there are a few cases known in which estimations are made possible just because of the occurrence of chemical induction). Therefore, many efforts have been directed at exploring at least qualitatively the source of errors caused by induced reactions. That is why our present knowledge about such reactions is rather qualitative in nature. 

This short and far from complete survey shows that the previously obscure field of chemical induction is becoming more and more understood. The accelerating pace of progress has furnished from the forties onwards a great deal of interesting information about the chemistry of unstable intermediates, e.g. chromium(V), chromium(IV), arsenic(IV), tin(III), HO2, OH, SO4 radicals. These results were obtained mostly by conventional methods. Therefore, it may be expected that the more extensive application of methods suitable for detection and estimation of short-living entities (e.g. resonance methods, fast reaction techniques) will enable our somewhat qualitative knowledge (as it is today) to be put onto a quantitative basis. 

In order to use Eqs. (2.6.1) and (2.6.2) to estimate the sensitivity gain obtained by remote detection, knowledge of the relative sensitivity of the detector and the encoding circuit, A, is required. Here we discuss the sensitivity of an rf coil detector as an example, because all the experiments presented in this text use inductive detection at high field. The signal-to-noise ratio of inductive NMR detection can be approximated by the following simplified equation [12] ... 

It is hoped that this volume will contribute toward the ultimate elucidation of the molecular mechanism of induction of cancer by PAH. This knowledge will provide a rational basis for the design of approaches for the prevention and cure of this dread disease. 

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