Asymmetric Hybrids: Dialogues for Computational Concept Combination

When people combine concepts these are often characterised as “hybrid”, “impossible”, or “humorous”. However, when simply considering them in terms of extensional logic, the novel concepts understood as a conjunctive concept will often lack meaning having an empty extension (consider “a tooth that is a chair”, “a pet flower”, etc.). Still, people use different strategies to produce new non-empty concepts: additive or integrative combination of features, alignment of features, instantiation, etc. All these strategies involve the ability to deal with conflicting attributes and the creation of new (combinations of) properties. We here consider in particular the case where a Head concept has superior ‘asymmetric’ control over steering the resulting concept combination (or hybridisation) with a Modifier concept. Specifically, we propose a dialogical approach to concept combination and discuss an implementation based on axiom weakening, which models the cognitive and logical mechanics of this asymmetric form of hybridisation.

Strategy Development as a Function of the Amount of Relevant or Irrelevant Information

The study examined the relationship between the amount of relevant or irrelevant information and subjects' strategies. Subjects solved 16 conjunctive concept-learning problems which varied in terms of the amount and type of information. The study measured the focusing strategy, the number of choices to solution, and the time to solution. Analysis indicated focusing scores were highest when the amount of information was lowest and relevant information was the source of the information. Other results suggest strategies developed over time.

Alternative Theories of Concept Identification among Older Adults

The purpose of the present experiment was to investigate some predictions of hypothesis testing and S-R association (frequency) theories regarding memory for intratrial events on a conjunctive concept-identification task. They have received extensive study with young adults but not with older subjects. The individual' events under investigation were feedback, responses, hypotheses, and stimuli. Hypothesis-testing theory requires subjects to retain information concerning the correct hypothesis from one trial to the next whereas frequency does not. 75 subjects (60–70 yr. old) participated in the study. Subjects had difficulty in recalling the correct hypothesis stated on previous trials. These errors occurred on problems with negative response trials, not with incorrect feedback. The results contradict predictions based on hypothesis-testing models but are consistent with frequency theory. Unlike in the studies based on younger adults, present subjects did not recall the hypothesis very well under the conditions in which hypothesis testing was made part of the primary task.

Some Thoughts on the Nature of Concrete Thinking

It is suggested that earlier criticism of the Goldsteirt-Scheerer Tests of Abstract and Concrete Thinking was based on an incorrect conceptualization of abstract and concrete thinking; and that, while ‘abstract’ thinking is a conjunctive concept, ‘concrete’ thinking is a disjunctive concept.

Feature Frequency and the Use of Negative Instances in a Geometric Task

A geomerric task was designed to investigate the effect of the frequency of irrelevant features in learning a conjunctive concept. One hundred algebra students were assigned to one of four treatment groups formed by crossing the two independent variables of feature frequency (equal or high) and sequence type (positive instances only or mixed positive and negative instances). The frequency of irrelevant features affected the usefulness of negative instances. When six irrelevant features were equally likely, positive instances were more helpful in learning, whereas when three irrelevant features predominated, mixed positive and negative instances were more helpful. The results may explain the difference between the findings of psychological and educational research on the usefulness of negative instances.

Comparative Effectiveness of Three Sequences of Moves for Teaching Conjunctive and Relational Mathematical Concepts to College Students

Three sequences of moves--characterization-exemplification (CED), exemplification (E), and a modified characterization-exemplification (CEI) or (OCED) were compared on the immediate acquisition and short-term retention of conjunctive and relational mathematical concepts. Twenty-seven general mathematics students were blocked into high- and low-achievement levels and randomly assigned to three treatment groups. The E-sequence was found to be significantly (p<.05) better than the CED and the CEI on the immediate acquisition Subtest 2 at the low achievement level and the high achievement level, respectively, for the conjunctive concept only.