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31.
Neil Tennant 《Topoi》1994,13(2):127-133
We define a system IR of first-order intuitionistic relevant logic. We show that intuitionistic mathematics (on the assumption that it is consistent) can be relevantized, by virtue of the following metatheorem: any intuitionistic proof of A from a setX of premisses can be converted into a proof in IR of eitherA or absurdity from some subset ofX. Thus IR establishes the same inconsistencies and theorems as intuitionistic logic, and allows one to prove every intuitionistic consequence of any consistent set of premisses.This paper grew out of discussion of a survey talk, on earlier work, that I gave to the 5th A.N.U. Paraconsistency Conference in January 1988. I am greatly indebted to the suggestion by Michael MacRobbie on that occasion that I investigate the so-called non-Ketonen form of the sequent rule for on the right. That suggestion inspired the correspondingly modified rule of Introduction in the system of natural deduction given above.  相似文献   
32.
The Human Genome Project has raised many issues regarding the contributions of genetics to a variety of diseases and societal conditions. With genetic testing now easily conducted with lowered costs in nonmedical domains, a variety of privacy issues must be considered. Such testing will result in the loss of significant privacy rights for the individual. Society must now consider such issues as the ownership of genetic data, confidentiality rights to such information, limits placed on genetic screening, and legislation to control genetic testing and its applications. There is often a conflict between individual rights to privacy and the need for societal protection.  相似文献   
33.
Previous studies have identified three categories of variables which influence decisions of mock jurors: type of crime, defendant characteristics, and personal characteristics of jurors. This study manipulated the following variables towards the ends of assessing their influence on mock jurors' sentencing severity: premeditated vs. unpremeditated murder, black vs. white defendant, low SES vs. high SES defendant. Only defendant SES predicted sentencing severity: low SES defendants were assigned significantly longer sentences than high SES defendants. None of the measures of juror characteristics correlated with sentencing severity. Failure to replicate significant relationships with most of these variables and sentencing severity suggest that results of studies which manipulate only one variable dimension may overestimate the influence of these variable dimensions in mock jurors' decisions.  相似文献   
34.
35.
Deficits in visual learning produced by posterior temporal lesions in cats   总被引:3,自引:0,他引:3  
Eight cats with lesions in the posterior temporal (PT) cortex, seven cats with lesions in the basolateral amygdala (BLA), and eight intact controls were observed on eight tests of visual discrimination learning and of spontaneous responses to salient visual stimuli. The effects of the two lesions were somewhat dissociable. The PT lesions were accompanied by a severe deficit in pattern discrimination learning but no loss in visual tracking or orientation to the silhouette of a threatening cat. The BLA lesions produced a milder and less consistent loss in pattern discrimination but serious defects in tracking and reponse to the cat silhouette. Both operated groups performed well on the visual cliff. The deficit from PT lesions appeared independent of damage to the geniculocortical system. The parallel of symptoms from PT lesions in cats and inferotemporal lesions in monkeys is discussed.  相似文献   
36.
Three-dimensional contingency tables are analyzed, with one variable (e.g., sex) as a factor, and with a natural relation between the other variables (e.g. left and right eye vision). Models of special interest, like symmetry and proportional symmetry between the related variables, and homogeneity across the factor levels, are investigated. Maximum likelihood estimators of parameters and partitions of chi-square goodness-of-fit statistics are explicitly presented; the independence of certain models is noted, and an example is discussed.  相似文献   
37.
Literature on sex differences in impulsivity has tended to focus on differences between groups, while ignoring relationships beyond zero order correlations. The purpose of this study was to evaluate Maccoby's hypothesis (1966) of opposite-direction correlations where the relationship between a set of variables (e.g., impulsivity and intellectual ability) is curvilinear, with males and females being systematically distributed on opposite sides of the curve. The Primary Mental Abilities (PMA) and Matching Familiar Figures tests were administered to 44 males and 49 females. The relationship between all of the PMA subtests and impulsivity was curvilinear for males, but linear for females on all but one of the subtests. The importance and implications of examining distribution differences rather than group differences are discussed.Support for this study has come from the Office of Research Administration, University of Kansas, Grant Number 3581-5038. This paper was presented in part at the meeting of the American Psychological Association, Chicago, August 1975, Division 7.  相似文献   
38.
Signal detection theory (SDT) allows a bias-free measure of sensitivity, d′, to be simply estimated from discrimination data when certain conditions are met. The computation is not straightforward, however, in several popular discrimination designs, such as two- and four-interval same-different designs and the ABX design. The present tables, derived from the SDT models of Macmillan, Kaplan, and Creelman (1977), make possible the estimation of d’ from these complex discrimination designs.  相似文献   
39.
Sixty-four male Wistar rats were given acquisition training in an enclosed straight-alley runway which could be adjusted for angles of inclination. The 2×2×2 design involved two angles of inclination in acquisition (0° and 40°) and two angles of inclination in extinction (0° and 40°). Between acquisition and extinction, half the subjects were exposed to a latent extinction procedure and half served as controls. Number of responses in a 30-min extinction session was an inverse function of effort required in extinction. Additionally, latent extinction procedures resulted in reduced resistance to extinction, but only when the effort conditions of acquisition and extinction were constant. When the effort conditions of acquisition and extinction were dissimilar, latent extinction procedures resulted in increased resistance to extinction. The results raise questions about the nature of the learning which occurs during latent extinction training.  相似文献   
40.
Special difficulties are encountered when attempting to provide intracranial cannulation of small animals that have floating or fragile skull bones. The technique described was developed for mice but seems applicable to other species. The cannula system is inexpensive and easy to use. A wound clip anchor seems superior to either skull screws or bonded acrylic, producing less damage to the brain and no necrosis of bone or tissue on the wound margin. Patency data up to 25 days is presented, and the system is as efficacious as other techniques.  相似文献   
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