Schematic Knowledge Research Articles

On search in an incomplete database

The purpose of this investigation is to determine the psychological factors which are important for the efficient use of information from an incomplete database. Ten psychology students were instructed to answer a question by searching for information in a database. The question was not directly answerable but required the subjects to make inferences from the information retrieved. The following differences were found between the most and the least efficient subjects: the more efficient subjects started by obtaining an overview of the alternative search words available. They used the information obtained both to find possible answers and to exclude impossible ones. The more efficient subjects used prior knowledge schemata to make inferences, which yielded fewer possible candidates than the prior knowledge schemata used by the less efficient subjects. The less efficient subjects became more confused by the different possibilities, forgot information retrieved and repeated searches. It was concluded than an efficient search in an incomplete database requires that people have an overview of the alternatives offered. It also requires that one should make inferences from the information obtained in order to form possible hypotheses and to reject impossible alternatives.

A theory of schema labelling

Schema labelling is a knowledge organization theory for recognition systems. In this theory, recognition constructs symbolic network descriptions of sensory data in terms of a stored knowledge base of schemas. A schema knowledge representation is formally specified. Each schema represents a class of objects by specifying class membership as a set of constraints on other classes. The constraints are based on two orthogonal relationships in knowledge organization: composition and specialization. Complex objects have internal structure which can be represented as composition constraints among their parts. Likewise, specialization constraints segment classes into subclasses by type. The description produced by schema labelling is a network consistency graph. The nodes of the graph are schema instances derived from the knowledge base. The domain for each instance is its finite set of subclasses and the network constraints are the constraints defined between schemas. Constraints are propagated in the network using an arc consistency algorithm mat has been adapted to schema representations. The constructed network description makes explicit the objects recognized in the data and their relationships. The graph is hierarchical, providing a description at multiple levels of detail. A hypothetical scene analysis system is used to illustrate the methodology.

Scripts in Organizational Behavior

The concept of a “script” is presented as a framework for understanding the cognitive dynamics underlying many organizational behaviors and actions. A script is a schematic knowledge structure held in memory that specifies behavior or event sequences that are appropriate for specific situations. “Script processing” is the performance of the behaviors or events contained in the knowledge structure. Many facets of organizational behavior can be effectively described, analyzed, and understood by using the script concept and processing notion.

Sentence frame contexts and lexical decisions: sentence-acceptability and word-relatedness effects.

Many studies have explored the effects of single-word contexts on visual word recognition, and several models have been proposed to account for the results obtained. However, relatively little is known about the effects of sentence contexts. In the experiment reported, the contexts consisted of sentences with the final word deleted, and subjects made word-nonword (lexical) decisions on target strings of letters. Norms were collected to determine the most common completion for each sentence frame. The experiment yielded three main findings: (1) Lexical decisions were fastest for words that were the most common completions; (2) among words not given as completions in the norming procedure, decisions were faster for words related to the most common completions than for words unrelated to the most common completions; t3t also among words that were not produced as completions, decisions were faster for words that formed acceptable completions than for words that did not. These relatedness and sentence-acceptability effects were independent, so that the relatedness effect held even when the target words formed anomalous sentence completions. In order to account for these results, a model combining two types of processes is required. In the model described, schematic knowledge (Rumelhart & Ortony, 1977) operates upon a semantic network to activate particular nodes, and this activation spreads to related concepts as in the Collins and Loftus (1975) model.

Abstraction and the Distinction of the Sciences

ION AND THE DISTINCTION OF THE SCIENCES !\.RECENT author 1 has treated of abstraction in regard to its objective basis and to the division of the speculative sciences. He notes that moderate realism requires an objective basis for the abstractive process of the intellect, and asserts that this basis can be found in the real composition of distinct principles which are combined in sensory things. There will be as many orders of abstraction as there are of real composition in these things. Three orders of composition can be found in sensory things, namely, the composition of substance with accidents, the composition of substantial form with primary matter, and the composition of essence with existence. In each of these three orders there is an act or formal principle combined with a potential subject, although both subject and form are diverse in the distinct cases, not similar. It is asserted that in regard to each of these three orders the intellect is able to grasp an act or formal principle apart from this or that potency. Thus there are three ascending orders of abstraction from sensory matter, each of which has a basis in objective reality, and according to which there is an increasingly deeper penetration of sensory being by the inquiring mind. It is suggested that the usual ordering of physical and mathematical abstraction is defective and should be the reverse. The real composition of substance with accident is the basis newly proposed for the abstraction which should be regarded as of the first degree. This composition is the more superficial, and yet it is the basis for the abstraction by which we attain the object of mathematical science. The real compo1 F. S. Connolly, "Science vs. Philosophy," The Modem Schoolman, XXIX (1952), 197-209; " Abstraction and Moderate Realism," The New Scholaaticism, XXVII, No. I, (1958), 72-90. 48 44 WILLIAM H. KANE sition of the substantial form with primary matter is the basis proposed for the second degree of abstraction, by which we attain the object of the philosophy of nature. This science is not very extensive, because there is only a small number of natural species to be· known philosophically. Modern natural science is distinct from the philosophy of nature, because it is merely empirical and schematic knowledge, and is not science in the Aristotelian sense of the term. The real composition of essence with existence is the basis proposed for a third degree of abstraction, by which we attain the object of metaphysics. Finally, the author inquires why St. Thomas was unable to correlate the three degrees of abstraction and the three kinds of speculative science with the distinct orders of real composition in sensory things, a correlation which seems to be demanded by moderate realism. To the present writer it seems that St. Thomas has clearly answered all of these and many other pertinent questions in his explanation of the fifth and sixth questions of the work On the Trinity by Boethius.2 But because this doctrine which St. Thomas explains and defends is not well known or well understood , we shall try to interpret it and apply it to the problems raised above. In doing so we shall depart somewhat from the order of the articles in the commentary by St. Thomas. The Angelic Doctor first proves that there are three and only three kinds or genera of speculative science, and then he proceeds to defend; characterize and compare the knowledge attained in each. For the present purpose we shall consider first what it is to abstract, and why we abstract. Then we shall try to see what is required for the validity of abstract knowledge, and finally what it is that distinguishes the different sciences. ABSTRACTION To abstract, says St. Thomas,8 is to consider separately things which are not really separated but are conjoined in reality. We abstract because we are not able to know things perfectly in • In Boet. de Trin. (ed. Paul Wyser. 0. P.; Fribourg, 1948). 3 Ibid., q. 5, a. S; II Physic., lect. S. ABSTRACTION AND THE DISTINCTION OF THE SCIENCES 45 their wealth of detail and intelligibility in a single act of knowing . What we cannot do in...