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The logic of failure.

Unlike other living creatures, humans can adapt to uncertainty. They can form hypotheses about situations marked by uncertainty and can anticipate their actions by planning. They can expect the unexpected and take precautions against it. In numerous experiments, we have investigated the manner in which humans deal with these demands. In these experiments, we used computer simulated scenarios representing, for example, a small town, ecological or economic systems or political systems such as a Third World country. Within these computer-simulated scenarios, the subjects had to look for information, plan actions, form hypotheses, etc.

Africa, Western↗

Modeling uncertainty in clinical diagnosis using fuzzy logic.

This paper describes a fuzzy approach to computer-aided medical diagnosis in a clinical context. It introduces a formal view of diagnosis in clinical settings and shows the relevance and possible uses of fuzzy cognitive maps. A constraint satisfaction method is introduced that uses the temporal uncertainty in symptom durations that may occur with particular diseases. The method results in an estimate of the stage of the disease if the temporal constraints of the disease in relation to the occurrence of the symptoms are satisfied. A lightweight fuzzy process is described and evaluated in the context of diagnosis of two confusable diseases. The process is based on the idea of an incremental simple additive model for fuzzy sets supporting and negating particular diseases. These are combined to produce an index of support for a particular disease. The process is developed to allow fuzzy symptom information on the intensity and duration of symptoms. Results are presented showing the effectiveness of the method for supporting differential diagnosis.

Algorithms↗

From fuzzy logic toward plurimonism: the science of active and empathic observation.

Plurimonism is a new philosophy and method of science. It holds that the revolution in computer science and artificial intelligence has reached the point that all the sciences in general can now account for the complex relations of an irreducible plurality of unique observers engaged in describing the same event. Plurimonism seeks to describe the conscious and unconscious relations of the scientific observer during the act of observation of a given event while preserving the historical uniqueness and indivisible identity of each such observer. Using the framework of plurimonism, we mathematically formulate the problem of empathy. This self-reflective mathematical model entails four components of the empathic process involving two observers. They are: 1) the self; 2) the self's-other; 3) the other; and 4) the other's-self. It measures the degree of accuracy of the therapist-observer's empathy, as well as conscious and unconscious processes involved in the patient-observer's idealization and the therapist-observer's confidence in clinical psychotherapy. Ratings are obtained from both patient and therapist from four different points of view. The plural views of the patient's global assessment of functioning (GAF) are from: 1) the therapist's view (TGAF); 2) the patient's view (PGAF); 3) the therapist empathic view (TEGAF), which represents the therapist's estimate of PGAF; and 4) the patient's empathic estimate of the TGAF. The GAF scale is the standard dimensional 100-point-scale measure used in psychiatry for recording a patient's functioning. The patient's estimate of the therapist's degree of accuracy as well as the therapist's confidence in his or her empathic accuracy is also represented. Three formulae are presented that describe the degree of the therapist's empathic accuracy, the patient's over-idealization/under-idealization, and the therapist's over-confidence/under-confidence. The concept of empathy is here restricted to mean the degree to which one observer can take the point of view of another observer when both are observing the same thing.

Cybernetics↗

Logic and motivation in risk research: a nuclear waste test case.

After two decades of massive investigation, federal approval of a nuclear waste site is drawing to a close. Large-scale research to assure that major hazards such as this one are socially acceptable is often highly inefficient, as here. A regulatory remedy would be to require not only that risk currently assessed be acceptable, but also that risk would remain acceptable given any new information. Research to test compliance with these rules has to be cost effective. Research activities should be managed according to an explicit discipline that can be imposed on powerful conflicting interests. They might be required to (1) set targets for the first- and second-order risk assessments, (2) allocate research resources to close any gap between current and target assessments cost effectively, and (3) reallocate resources, as evolving findings dictate. The interests of license applicant (Department of Energy, DOE) and society are distinguished: the former would want the application approved; the latter would want to reject an unacceptable facility.

Environment↗

Constant capacity in an immediate serial-recall task: a logical sequel to Miller (1956).

We assessed a hypothesis that working memory capacity should include a constant number of separate mental units, or chunks (cf. Miller, 1956). Because of the practical difficulty of measuring chunks, this hypothesis has not been tested previously, despite wide attention to Miller's article. We used a training procedure to manipulate the strength of associations between pairs of words to be included in an immediate serial-recall task. Although the amount of training on associations clearly increased the availability of two-item chunks and therefore the number of items correct in list recall, the number of total chunks recalled (singletons plus two-word chunks) appeared to remain approximately constant across association strengths, supporting a hypothesis of constant capacity.

Adult↗

Choose and choose again: appearance-reality errors, pragmatics and logical ability.

In the Appearance/Reality (AR) task some 3- and 4-year-old children make perseverative errors: they choose the same word for the appearance and the function of a deceptive object. Are these errors specific to the AR task, or signs of a general question-answering problem? Preschoolers completed five tasks: AR; simple successive forced-choice question pairs (QP); flexible naming of objects (FN); working memory (WM) span; and indeterminacy detection (ID). AR errors correlated with QP errors. Insensitivity to indeterminacy predicted perseveration in both tasks. Neither WM span nor flexible naming predicted other measures. Age predicted sensitivity to indeterminacy. These findings suggest that AR tests measure a pragmatic understanding; specifically, different questions about a topic usually call for different answers. This understanding is related to the ability to detect indeterminacy of each question in a series. AR errors are unrelated to the ability to represent an object as belonging to multiple categories, to working memory span, or to inhibiting previously activated words.

Auditory Perception↗

Using fuzzy logic to confirm the integrity of a pattern recognition algorithm for long genomic sequences: the W-curve.

The W-curve is a numerical mapping algorithm that provides tertiary information content of long and short genomic sequences. The most popular genomic pattern recognition algorithms depend on string matching of the primary information content of short genomic sequences. Herein, we describe a way to define the fuzzy properties of the W-curve. This approach improves a distance (dissimilarity) between two or more homologous long genomic sequences. Fourier analysis of W-curves delivers a smoother function for gap-stripped regions. Calculation of respective Fourier energies may improve the accuracy of the distance metric used to generate a phylogenetic tree of analyzed genomic sequences. This is especially the case for long genomic sequences that have been gap-stripped and aligned with the aid of previously published heuristic methods. These previous methods involved W-curve alignments used in concert with such programs as Clustal that use linear dynamic programming to align multiple gap-stripped W-curves.

Algorithms↗