• Title/Summary/Keyword: Roger White

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Is Bayesianism Favorable to Dogmatism? (베이즈주의는 독단론에 호의적인가?)

  • Yoon, Bosuk
    • Korean Journal of Logic
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    • v.18 no.2
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    • pp.243-264
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    • 2015
  • Roger White raised an objection, one based on Bayesianism, to the dogmatist view of perceptual justification. In his paper, "Perceptual Dogmatism and Bayesian Favoring", Ilho Park tries to show, contra Roger White, that there is no real conflict between Perceptual dogmatism and Bayesianian theory of confirmation. For this purpose, Park brings in the notions of the degree of confirmation and the favoring relation and argues that Bayesian theory, when properly understood, can yield results that are quite favorable to dogmatism. I don't think, however, that the devices that he employes actually deliver what he promises. The conflict is yet to be resolved. Probably, Bayesian theorists may be better off if they, instead of trying to resolve the conflict, consider the option of simply rejecting dogmatism.

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A New Suggestion on the Bayesianism Problem for Epistemic Dogmatism (인식적 독단론에 제기되는 베이즈주의적 비판에 대한 새로운 제안)

  • Hong, Yeri
    • Korean Journal of Logic
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    • v.18 no.3
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    • pp.389-436
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    • 2015
  • Epistemic dogmatism claims that if it seems P to you then you have immediate justification to believe P. The view has been faced with a problem that it is incompatible with Bayesianism, especially raised by Roger White(2006). James Pryor(2013), defending epistemic dogmatism, has given a reply for the problem. In this paper, first, I show some problems on Pryor's reply. Then, I present a new kind of suggestion to deal with the problem, which avoids problems Pryor's reply has. Finally, I suggest a different diagnosis on the problem.

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Perceptual Dogmatism and Bayesian Favoring (지각적 독단론과 베이즈주의 호의성)

  • Park, Ilho
    • Korean Journal of Logic
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    • v.17 no.3
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    • pp.399-424
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    • 2014
  • The main objective of this paper is to examine critically White's claim that there is a conflict between Perceptual Dogmatism and Bayesian Theory of Confirmation. For this purpose, this paper is structured as follows: In Section 2, I will introduce White's argument. Section 3 is dedicated to explaining some elements of Bayesian Theory of Confirmation. In particular, I will provide an explanation of confirmation measures and Bayesian Favoring. Using these two conceptual apparatuses, it will be shown that, contrary to what White has thought, there is a way of supporting Perceptual Dogmatism by means of Bayesian Theory of Confirmation - in particular, Bayesian Theory of Favoring.

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A Critical Evaluation of DNA Adducts as Biological Markers for Human Exposure to Polycyclic Aromatic Compounds

  • Godschalk, Roger W.L.;Van Schooten, Frederik-Jan;Bartsch, Helmut
    • BMB Reports
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    • v.36 no.1
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    • pp.1-11
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    • 2003
  • The causative role of polycyclic aromatic hydrocarbons (PAH) in human carcinogenesis is undisputed. Measurements of PAH-DNA adduct levels in easily accessible white blood cells therefore represent useful early endpoints in exposure intervention of chemoprevention studies. The successful applicability of DNA adducts as early endpoints depends on several criteria:i.adduct levels in easily accessible surrogate tissues should reflect adduct levels in target-tissues, ii. toxicokinetics and the temporal relevance should be properly defined.iii. sources of inter- and intra-individual variability must be known and controllable, and finally iv. adduct analyses must have advantages as compared to other markers of PAH-exposure. In general, higher DNA adduct levels or a higher proportion of subjects with detectable DNA adduct levels were found in exposed individuals as compared with non-exposed subjects, but saturation may occur at high exposures. Furthermore, DNA adduct levels varied according to changes in exposure, for example smoking cessation resulted in lower DNA adduct levels and adduct levels paralleled seasonal variations of air-pollution. Intra-individual variation during continuous exposure was low over a short period of time (weeks), but varied significantly when longer time periods (months) were investigated. Inter-individual variation is currently only partly explained by genetic polymorphisms in genes involved in PAH-metabolism and deserves further investigation. DNA adduct measurement may have three advantages over traditional exposure assessment: i. they can smooth the extreme variability in exposure which is typical for environmental toxicants and may integrate exposure over a longer period of time. Therefore, DNA adduct assessment may reduce the monitoring effort. ii. Biological monitoring of DNA adducts accounts for all exposure routes. iii. DNA adducts may account for inter-individual differences in uptake, elimination, distribution, metabolism and repair amongst exposed individuals. In conclusion, there is now a sufficiently large scientific basis to justify the application of DNA adduct measurement as biomarkers in exposure assessment and intervention studies. Their use in risk-assessment, however, requires further investigation.

Performance and carcass characteristics of Australian purebred and crossbred lambs supplemented with Rice Bran

  • Flakemore, Aaron Ross;Otto, John Roger;Suybeng, Benedicte;Balogun, Razaq Oladimeji;Malau-Aduli, Bunmi Sherifat;Nichols, Peter David;Malau-Aduli, Aduli Enoch Othniel
    • Journal of Animal Science and Technology
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    • v.57 no.10
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    • pp.36.1-36.9
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    • 2015
  • Background: This study examined the effects of dietary supplementation with rice bran, sire breed and gender on live animal performance and carcass characteristics in Australian crossbred and purebred Merino lambs. Methods: Forty-eight lambs balanced by sire breed (Dorset, White Suffolk, Merino) and gender (ewe, wether) were randomly allocated into three dietary supplementation groups (Control- 24 lambs fed wheat/barley-based pellets, Low- 12 animals fed a 50/50 ratio of wheat-based/rice bran pellets, and High- 12 lambs fed rice bran pellets). The Rice bran pellets replaced 19 % of the barley component of the feed. Animals were group-fed at the rate of 1000 g of the supplement per head per day with ad libitum access to lucerne hay as the basal diet and water. The duration of the feeding trial was 49 days with an initial 21-day adjustment period. Results: Sire breed differences were evident for initial (p < 0.0002) and final (p < 0.0016) liveweights, hot carcass (p < 0.0030) and cold carcass (p < 0.0031) weights, as well as dressing percentage (p < 0.0078), fat thickness (p < 0.0467), yield grade (p < 0.0470) and rib eye area (p < 0.0022) with purebred Merino under-performing compared to the crossbreds. Concentrate feed conversion efficiency, costs per unit of liveweight gain and over the hooks income were comparable between treatments regardless of the observed trend where the high supplementation group tended to show lower feed intake (745.8 g/day) compared to both the control (939.9 g/day) and low supplementation groups (909.6 g/day). No significant differences (p > 0.05) were observed between treatments for live animal performance, carcass characteristics, gender and their second-order interactions. Conclusions: Results indicate that Rice bran can be utilised as a cost-effective supplementary feed source in genetically divergent sheep over a 49-day feeding period without detrimental effects on overall live animal performance or carcass characteristics.