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Best Explanation (best + explanation)
Selected AbstractsBEST EXPLANATION AND SCIENTIFIC REALISMPHILOSOPHICAL FORUM, Issue 2 2007YVONNE RALEY First page of article [source] Abductive Diagnosis Using Time-Objects: Criteria for the Evaluation of SolutionsCOMPUTATIONAL INTELLIGENCE, Issue 1 2001Elpida T. Keravnou Diagnostic problem solving aims to account for, or explain, a malfunction of a system (human or other). Any plausible potential diagnostic solution must satisfy some minimum criteria relevant to the application. Often there will be several plausible solutions, and further criteria will be required to select the "best" explanation. Expert diagnosticians may employ different, complex criteria at different stages of their reasoning. These criteria may be combinations of some more primitive criteria, which therefore should be represented separately and explicitly to permit their flexible and transparent combined usage. In diagnostic reasoning there is a tight coupling between the formation of potential solutions and their evaluation. This is the essence of abductive reasoning. This article presents an abductive framework for diagnostic problem solving. Time-objects, an association of a property and an existence, are used as the representation formalism and a number of primitive, general evaluation criteria into which time has been integrated are defined. Each criterion provides an intuitive yardstick for evaluating the space of potential solutions. The criteria can be combined as appropriate for particular applications to define plausible and best explanations. The central principle is that when time is diagnostically significant, it should be modeled explicitly to enable a more accurate formulation and evaluation of diagnostic solutions. The integration of time and primitive evaluation criteria is illustrated through the Skeletal Dysplasias Diagnostician (SDD) system, a diagnostic expert system for a real-life medical domain. SDD's notions of plausible and best explanation are reviewed so as to show the difficulties in formalizing such notions. Although we illustrate our work by medical problems, it has been motivated by consideration of problems in a number of other domains (fermentation monitoring, air and ground traffic control, power distribution) and is intended to be of wide applicability. [source] Sex Differences in Feeding Activity Results in Sexual Segregation of Feral GoatsETHOLOGY, Issue 5 2008Robin I. M. Dunbar Sexual segregation is common in ungulates. We show, in a high latitude population of feral goats where behavioural synchrony and fission rates have been shown to be the best explanation for segregation, that it is differences explicitly in the feeding time requirements of the two sexes (but not those for other activities) that best explains the variations in monthly frequencies of segregation. However, this effect is less marked during winter months when short day length forces the time budgets of the two sexes to converge. We argue that the various explanations for segregation can best be interpreted as separate factors in a multivariate model in which species- and habitat-specific weightings influence the relative importance of these variables, and thus the likelihood that segregation will occur. [source] Age-period-cohort analysis of dentist use in Spain from 1987 to 1997.EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2001An analysis based on the Spanish National Health Interview Surveys The aim was to determine whether the effects of age, period (from 1987 to 1997), or cohort (birth-cohort) are the most plausible explanations for the variation in dentist utilisation over time in Spain. On the basis of three sequential Spanish National Health Surveys, the trend in the percentage of people visiting the dentist within the previous 3 months was analysed by means of a standard cohort table and by the Clayton & Schifflers method. The percent of people visiting the dentist grew from 13.6% in 1987, to 17.2% in 1997. Visual examination of the cohort table, together with the fit of the age-cohort model, indicates that cohort succession may be the best explanation for the increase. The younger the cohort, the higher the dental visit rate; this relationship was strongest for people born after 1977. The model also indicates that the rates of dental visiting tend to increase up to middle age, and then tend to decrease with age. [source] Soil and atmospheric water deficits and the distribution of New Zealand's indigenous tree speciesFUNCTIONAL ECOLOGY, Issue 2 2001Leathwick J. R. Summary 1.,An extensive data set describing the composition of New Zealand's remaining indigenous forests was used to estimate the degree of correlation between measures of both soil and atmospheric water deficit and the distribution of common tree species. 2.,For most species, regression models incorporating measures of air saturation deficit in early autumn, as well as an annual integral of root zone water deficit, provided the best explanation of spatial distribution. This accords strongly with the mechanistic effects of air saturation deficits on transpiration from trees, and the hydraulic risks experienced by trees under high evaporative demand. 3.,Adjustment of root zone water deficits to account for reductions in rainfall in dry years substantially improved model predictions. This suggests that extreme climatic events, such as the El Niņo phase of the Southern Oscillation, are likely to have strongly influenced the historic composition of forests in New Zealand's drier eastern lowlands. [source] When and How Regions Become Peaceful: Potential Theoretical Pathways to Peace,INTERNATIONAL STUDIES REVIEW, Issue 2 2005Benjamin Miller The objective of this essay is to address the following two puzzles. First, what best accounts for the transition from war to peace in different regions at different times? Second, what is the best explanation for variations in the level of regional peace that exists in different regions in a particular time period? Consider the differences that exist today in the Middle Eastern, South American, and Western European regions. A theoretical framework is proposed that is intended to integrate the regional and international perspectives on regional peace. It establishes linkages between different mechanisms that can lead to regional peace and the emergence of different levels of peace as well as presents three potential theoretical pathways to peace. An argument is made that the underlying cause of regional war propensity is the extent of the state-to-nation imbalance in a region. Accordingly, different peacemaking strategies produce different levels of peace based on their treatment of the state-to-nation problem. A distinction is made between the effects of different approaches to peacemaking and the conditions for their success. In effect, peacemaking strategies bring about the transition from war to peace only if certain conditions exist in the region. The advantages and disadvantages of the three mechanisms are illustrated through three case studies, each exemplifying a specific strategy and level of peace that have resulted from the presence of certain conditions in the region: the Middle East (a transition to cold peace in the 1990s), South America (the evolution of normal peace across the twentieth century), and Western Europe (the emergence of warm peace since the 1950s). [source] Are Banks Still Special?JOURNAL OF APPLIED CORPORATE FINANCE, Issue 1 2000New Evidence on Their Role in the Corporate Capital-Raising Process Bankers appear to play a special role in providing commitment-based financing to corporations. This type of lending is important not only for small firms that lack access to public debt markets but for large and medium-size companies as well. For such companies, commitment-based financing provides access to debt capital that becomes valuable when the firm has an immediate need for funding but interest rates in public debt markets are prohibitively high, or the firm is undervalued by the market. A good example of this was provided by the Asian crisis in the last quarter of 1998, when $10 billion of commercial paper was retired and $20 billion of net new commercial loans were booked. The authors also suggest that the fact that commitment-based financing is used by larger companies when they believe themselves to be undervalued in the market is probably the best explanation of why announcements of these types of loans elicit a positive stock price reaction. [source] The biogeography of Gunnera L.: vicariance and dispersalJOURNAL OF BIOGEOGRAPHY, Issue 7 2003Livia Wanntorp Abstract Aim The genus Gunnera is distributed in South America, Africa and the Australasian region, a few species reaching Hawaii and southern Mexico in the North. A cladogram was used to (1) discuss the biogeography of Gunnera and (2) subsequently compare this biogeographical pattern with the geological history of continents and the patterns reported for other Southern Hemisphere organisms. Location Africa, northern South America, southern South America, Tasmania, New Zealand, New Guinea/Malaya, Hawaii, North America, Antarctica. Methods A phylogenetic analysis of twenty-six species of Gunnera combining morphological characters and new as well as published sequences of the ITS region, rbcL and the rps16 intron, was used to interpret the biogeographical patterns in Gunnera. Vicariance was applied in the first place and dispersal was only assumed as a second best explanation. Results The Uruguayan/Brazilian Gunnera herteri Osten (subgenus Ostenigunnera Mattfeld) is sister to the rest of the genus, followed sequentially upwards by the African G. perpensa L. (subgenus Gunnera), in turn sister to all other, American and Australasian, species. These are divided into two clades, one containing American/Hawaiian species, the other containing all Australasian species. Within the Australasian clade, G. macrophylla Blume (subgenus Pseudogunnera Schindler), occurring in New Guinea and Malaya, is sister to a clade including the species from New Zealand and Tasmania (subgenus Milligania Schindler). The southern South American subgenus Misandra Schindler is sister to a clade containing the remaining American, as well as the Hawaiian species (subgenus Panke Schindler). Within subgenus Panke, G. mexicana Brandegee, the only North American species in the genus, is sister to a clade wherein the Hawaiian species are basal to all south and central American taxa. Main conclusions According to the cladogram, South America appears in two places, suggesting an historical explanation for northern South America to be separate from southern South America. Following a well-known biogeographical pattern of vicariance, Africa is the sister area to the combined southern South America/Australasian clade. Within the Australasian clade, New Zealand is more closely related to New Guinea/Malaya than to southern South America, a pattern found in other plant cladograms, contradictory to some of the patterns supported by animal clades and by the geological hypothesis, respectively. The position of the Tasmanian G. cordifolia, nested within the New Zealand clade indicates dispersal of this species to Tasmania. The position of G. mexicana, the only North American species, as sister to the remaining species of subgenus Panke together with the subsequent sister relation between Hawaii and southern South America, may reflect a North American origin of Panke and a recolonization of South America from the north. This is in agreement with the early North American fossil record of Gunnera and the apparent young age of the South American clade. [source] Relativism, Absolutism, and ToleranceMETAPHILOSOPHY, Issue 4 2003Hye-Kyung Kim Abstract: A common view is that relativism requires tolerance. We argue that there is no deductive relation between relativism and tolerance, but also that relativism is not incompatible with tolerance. Next we note that there is no standard inductive relation between relativism and tolerance,no inductive enumeration, argument to the best explanation, or causal argument links the two. Two inductive arguments of a different sort that link them are then exposed and criticized at length. The first considers relativism from the objective point of view ,of the universe', the second from the subjective point of view of the relativist herself. Both arguments fail. There is similarly no deductive relation between absolutism and tolerance,neither entails the other,and no inductive connection of any sort links the two. We conclude that tolerance, whether unlimited or restricted, is independent of both relativism and absolutism. A metaethical theory that says only that there is one true or valid ethical code, or that there is a plurality of equally true or valid ethical codes, tells us nothing about whether we should be tolerant, much less how tolerant we should be. [source] In Defence of Associative Political Obligations: Part OnePOLITICAL STUDIES, Issue 3 2006John Horton Part One of this article seeks to defend the idea of associative political obligations against a number of criticisms that have been advanced opposing it. The purpose of this defence is not to demonstrate that the associative account is therefore the best explanation of political obligations, but only that the principal reasons which have been given for rejecting it are much less compelling than its critics maintain. The argument focuses in particular on the various criticisms advanced by A. John Simmons. Two general lines of defence figure especially prominently. First, it is shown how many of the criticisms in one way or another ultimately rest on the assumption that political obligations must be voluntarily acquired, when it is just this assumption that is contested by an associative account. Secondly, it rebuts the charge that the idea of associative obligations faces a particular problem because it entails the view that members must have obligations to associations or groups that are evil. While it is not claimed that the idea of associative political obligations is entirely without difficulties, it is contended that stories of its demise are greatly exaggerated, and in this respect the ground is laid for Part Two of the article, which sketches a particular account of associative political obligations. [source] Pharmacological Mechanisms of Naltrexone and Acamprosate in the Prevention of Relapse in Alcohol DependenceTHE AMERICAN JOURNAL ON ADDICTIONS, Issue 2003John Littleton M.B.B.S., Ph.D. Naltrexone and acamprosate may ultimately prove to be useful additions to pharmacotherapy for alcoholism by reducing relapse. Naltrexone is a relatively selective competitive antagonist at mu-opioid receptors, and this activity may explain its anti-relapse action either because endogenous opioids are involved in the positively reinforcing effects of alcohol and/or because these same transmitters are involved in the conditioned anticipation of these effects. In contrast, the pharmacology of acamprosate is still poorly understood. This is not surprising because it is a small flexible molecule with similarities to several neuro-active amino acids and is used in high doses. All these factors suggest that it may have multiple actions. Currently, the best explanation for the effects of acamprosate seems to be that it inhibits the glutamatergic transmitter system involved in both the negative reinforcing effects of alcohol and the conditioned "pseudo-withdrawal" that may be important in cue-induced relapse. [source] THE RESPONSIBILITY OF SOLDIERS AND THE ETHICS OF KILLING IN WARTHE PHILOSOPHICAL QUARTERLY, Issue 229 2007Yitzhak Benbaji According to the purist war ethic, the killings committed by soldiers fighting in just wars are permissible, but those committed by unjust combatants are nothing but murders. Jeff McMahan asserts that purism is a direct consequence of the justice-based account of self-defence. I argue that this is incorrect: the justice-based conception entails that in many typical cases, killing unjust combatants is morally unjustified. So real purism is much closer to pacifism than its proponents would like it to be. I conclude that the best explanation of the common view that unjust combatants may be defensively killed relies on a rights-based conception of self-defence. [source] Abductive Diagnosis Using Time-Objects: Criteria for the Evaluation of SolutionsCOMPUTATIONAL INTELLIGENCE, Issue 1 2001Elpida T. Keravnou Diagnostic problem solving aims to account for, or explain, a malfunction of a system (human or other). Any plausible potential diagnostic solution must satisfy some minimum criteria relevant to the application. Often there will be several plausible solutions, and further criteria will be required to select the "best" explanation. Expert diagnosticians may employ different, complex criteria at different stages of their reasoning. These criteria may be combinations of some more primitive criteria, which therefore should be represented separately and explicitly to permit their flexible and transparent combined usage. In diagnostic reasoning there is a tight coupling between the formation of potential solutions and their evaluation. This is the essence of abductive reasoning. This article presents an abductive framework for diagnostic problem solving. Time-objects, an association of a property and an existence, are used as the representation formalism and a number of primitive, general evaluation criteria into which time has been integrated are defined. Each criterion provides an intuitive yardstick for evaluating the space of potential solutions. The criteria can be combined as appropriate for particular applications to define plausible and best explanations. The central principle is that when time is diagnostically significant, it should be modeled explicitly to enable a more accurate formulation and evaluation of diagnostic solutions. The integration of time and primitive evaluation criteria is illustrated through the Skeletal Dysplasias Diagnostician (SDD) system, a diagnostic expert system for a real-life medical domain. SDD's notions of plausible and best explanation are reviewed so as to show the difficulties in formalizing such notions. Although we illustrate our work by medical problems, it has been motivated by consideration of problems in a number of other domains (fermentation monitoring, air and ground traffic control, power distribution) and is intended to be of wide applicability. [source] | ||||||||||||||||