4,228 research outputs found
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Semantic memory redux: an experimental test of hierarchical category representation
Four experiments investigated the classic issue in semantic memory of whether people organize categorical information in hierarchies and use inference to retrieve information from them, as proposed by Collins & Quillian (1969). Past evidence has focused on RT to confirm sentences such as “All birds are animals” or “Canaries breathe.” However, confounding variables such as familiarity and associations between the terms have led to contradictory results. Our experiments avoided such problems by teaching subjects novel materials. Experiment 1 tested an implicit hierarchical structure in the features of a set of studied objects (e.g., all brown objects were large). Experiment 2 taught subjects nested categories of artificial bugs. In Experiment 3, subjects learned a tree structure of novel category hierarchies. In all three, the results differed from the predictions of the hierarchical inference model. In Experiment 4, subjects learned a hierarchy by means of paired associates of novel category names. Here we finally found the RT signature of hierarchical inference. We conclude that it is possible to store information in a hierarchy and retrieve it via inference, but it is difficult and avoided whenever possible. The results are more consistent with feature comparison models than hierarchical models of semantic memory
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Material Morphology and energy barriers to electrical ageing
A distribution of the parameters representing activation energy of the ageing process within the Dissado-Montanari-Mazzanti (DMM) lifetime model has been shown to model experimental lifetime distributions of PET films well. The results imply small differences in the local environments of the moieties involved in the ageing process. Very small changes in the minimum activation energy values have a pronounced effect on the resultant lifetimes of polymer specimens. Changes in the distributions of activation energies with field and temperature can be explained by assuming the ageing process to be one whereby polymer segments on lamella surfaces crystallise to create free volume within the polymer
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The Rumsfeld Effect: The unknown unknown
A set of studies tested whether people can use awareness of ignorance to provide enhanced test consistency over time if they are allowed to place uncertain items into a “don’t know” category. For factual knowledge this did occur, but for a range of other forms of knowledge relating to conceptual knowledge and personal identity, no such effect was seen. Known unknowns would appear to be largely restricted to factual kinds of knowledge
Experimental Evidence for Quantum Structure in Cognition
We proof a theorem that shows that a collection of experimental data of
membership weights of items with respect to a pair of concepts and its
conjunction cannot be modeled within a classical measure theoretic weight
structure in case the experimental data contain the effect called
overextension. Since the effect of overextension, analogue to the well-known
guppy effect for concept combinations, is abundant in all experiments testing
weights of items with respect to pairs of concepts and their conjunctions, our
theorem constitutes a no-go theorem for classical measure structure for common
data of membership weights of items with respect to concepts and their
combinations. We put forward a simple geometric criterion that reveals the non
classicality of the membership weight structure and use experimentally measured
membership weights estimated by subjects in experiments to illustrate our
geometrical criterion. The violation of the classical weight structure is
similar to the violation of the well-known Bell inequalities studied in quantum
mechanics, and hence suggests that the quantum formalism and hence the modeling
by quantum membership weights can accomplish what classical membership weights
cannot do.Comment: 12 pages, 3 figure
The Princess and the Pea: The Assurance of Voluntary Compliance Between the Texas Attorney General and Aetna\u27s Texas HMOs and Its Impact on Financial Risk Shifting by Managed Care
The Texas Attorney General attempts to regulate managed care organizations and their shifting of financial risk by utilizing Assurance Voluntary Compliance to make the costs associated with the provisions of health insurance more transparent. A primary technique used to shift financial risk to providers of healthcare services is through the use of downstream entities which are commonly provider-sponsored organizations. It is the relationship between the downstream entity and the individual physicians that ultimately affects patient care, the doctor-patient relationship, and the quality of care. The regulatory community throughout the United States has made the regulation of downstream entities its number one priority.
It was in this context that then-Texas Attorney General Dan Morales filed suit against six health maintenance organizations (“HMO”) in December 1998, which ultimately led to the creation of Assurance Voluntary Compliance. The Assurance Voluntary Compliance led to HMO’s introducing “consumer driven” health plans. These new health plans call for the consumer to bear a greater responsibility of risk. In effect, the consumer is being called upon to assume the role of insurer in the consumer’s own health care expenditures. In the long term, it is unlikely that consumers will be able to manage risk, control costs, and ensure quality better than the managed care industry, employers, and health care providers that the consumers will be forced to replace
Meaning-focused and Quantum-inspired Information Retrieval
In recent years, quantum-based methods have promisingly integrated the
traditional procedures in information retrieval (IR) and natural language
processing (NLP). Inspired by our research on the identification and
application of quantum structures in cognition, more specifically our work on
the representation of concepts and their combinations, we put forward a
'quantum meaning based' framework for structured query retrieval in text
corpora and standardized testing corpora. This scheme for IR rests on
considering as basic notions, (i) 'entities of meaning', e.g., concepts and
their combinations and (ii) traces of such entities of meaning, which is how
documents are considered in this approach. The meaning content of these
'entities of meaning' is reconstructed by solving an 'inverse problem' in the
quantum formalism, consisting of reconstructing the full states of the entities
of meaning from their collapsed states identified as traces in relevant
documents. The advantages with respect to traditional approaches, such as
Latent Semantic Analysis (LSA), are discussed by means of concrete examples.Comment: 11 page
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