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121.
Mark Balaguer 《Synthese》1995,103(3):303-325
A response is given here to Benacerraf's 1973 argument that mathematical platonism is incompatible with a naturalistic epistemology. Unlike almost all previous platonist responses to Benacerraf, the response given here is positive rather than negative; that is, rather than trying to find a problem with Benacerraf's argument, I accept his challenge and meet it head on by constructing an epistemology of abstract (i.e., aspatial and atemporal) mathematical objects. Thus, I show that spatio-temporal creatures like ourselves can attain knowledge about mathematical objects by simply explaininghow they can do this. My argument is based upon the adoption of a particular version of platonism — full-blooded platonism — which asserts that any mathematical object which possiblycould exist actuallydoes exist.I would like to thank the following people for their helpful comments on earlier versions of this paper: Arnold Koslow, Hartry Field, Jerrold Katz, Michael Resnik, Elliott Mendelson, Charles Landesman, Stephen Schiffer, Adam Vinueza, David Pitt, Jody Azzouni, David MacCallum, Colin McLarty, Tom Slaughter, Henry Mendell, Penelope Maddy, Michael Liston, Ricardo Gomez, Seth Crook, Stuart Cornwell, and various people at the University of Colorado, Boulder, where I read this paper in February, 1994. Much of the research for this paper was carried out under a City University of New York Dissertation Fellowship; I am grateful for this.  相似文献   
122.
College counseling can best be understood as the intersection of a professional activity and an environment. The specialty has developed from the merging of several movements: vocational guidance, mental health, and student personnel work. These elements are reflected in the diversity of backgrounds and perspectives represented by college counselors and in differing models of counseling services. College counseling will be affected by trends including health care reform, scarcity of resources in higher education, changing student demographics, and complex societal issues.  相似文献   
123.
Frame multiplicity and policy fiascoes: Limits to explanation   总被引:1,自引:0,他引:1  
The dynamics of intractability, frame multiplicity and intense controversy not only characterize policy formation struggles, as described by Schön and Rein, but also affect the evaluation of policies and government action. Policy analysts play an important part in the politics of policy evaluation. This article demonstrates that they tend to produce very different explanations for controversial, failing policies. Such differing explanations imply different causal attributions, different allocations of blame, and different lessons for future policy-making. Such differences are not random occurrences; they are embedded in the analytical frames that evaluators use to reconstruct policy processes and to explain their outcomes. It is shown that at least three deep-rooted frames can be reconstructed: fiascoes as failures of public problem solving, fiascoes as institutional imbalances, and fiascoes as system artefacts. One of the great epistemological challenges is how to deal with multiple analytical frames. The final part of the article discusses various strategies.  相似文献   
124.
Abstract— Does group discussion and deliberation on one issue or task influence the members' decisions or opinions on other issues? In contrast to past research looking solely at changes in responses to the same item discussed by the group, this study examined whether group interaction results in members changing the way they make judgments on related items in the future. The results show that group discussion and consensus on one set of judgments led to a significant convergence of judgmental strategies that extended to a related (but different) set of judgments the members made later as individuals.  相似文献   
125.
The purpose of the current study was to evaluate the school performance of residential youth who attended a public school setting. Direct comparisons were made between the residential youth and students in the community on a number of school measures. Results from a multivariate analysis of covariance indicated that the residential students had significantly lower grades, participated in significantly fewer extracurricular activities, and exhibited more problematic behaviors such as tardies and absences. These findings were consistent with previous research which found that many residential youth have a number of behavioral, social, and academic difficulties that interfere with school functioning. A number of recommendations were made regarding educational placement for residential youth.  相似文献   
126.
In the present study, a naturalistic functional analysis procedure was used to assess the effect of environmental stimulation on the stereotypic behavior (body rocking) of an adult whose stereotypy appeared to be induced by an acquired brain injury. Environmental stimulation, operationalized in terms of both physical and social characteristics, resulted in only minimal changes in the occurrence of body rocking. Body rocking occurred in excess of 50% of the observations in all environmental stimulation conditions and in a naturally occurring baseline condition. To our knowledge, this is the first published report of a functional analysis of stereotypy associated with acquired brain injury.  相似文献   
127.
Extinguishing a fixation point shortly before, or concurrently with, the onset of a peripheral visual target reduces the latency of saccades to that target. Saslow (1967) hypothesized that thisgap effect might occur because fixation point offsets reduce the incidence of corrective microsaccades with an associated saccadic refractory period. In the present study, a robust gap effect was obtained. However, using a Purkinje image eyetracker with 1 arcmin of resolution, we found that fixation point offsets had no effect on the occurrence of microsaccades and that the occurrence of microsaccades had no impact on the magnitude of the gap effect. Microsaccades therefore do not appear to play any part in the production of the gap effect.  相似文献   
128.
Cortisol can be used to indicate stress level as well as to monitor certain disease states. Although cortisol can be sampled from blood and urine, saliva sampling has decided advantages. Unfortunately, whole saliva contains a number of substances that can metabolize or bind with cortisol, potentially confounding analysis and quantitation. We introduce a semipermeable pouch that accumulates a contaminant-free salivary ultrafiltrate, thereby overcoming a number of the problems encountered with whole saliva. In three studies, we demonstrate accuracy and utility of the device for cortisol determination: (1) in an artificial medium, 60%–77% of the cortisol was recovered in the ultrafiltrate; (2) in vivo, ultrafiltrate cortisol correlated highly with whole-saliva cortisol collected under ideal conditions; and (3) ultrafiltrate cortisol evinced positive relationships with depression and cigarette use, consistent with studies in the literature. We conclude that this device and saliva-filtering technologies in general are useful in applications requiring quantitation of cortisol.  相似文献   
129.
A technique is described for rapidly collecting responses in auditory-localization experiments. Subjects indicate the perceived direction of the sound by pointing at a 20-cm-diam spherical model. In Experiment 1, the subjects judged the direction of a broadband signal, which could originate from any of 239 directions ranging through 360° of azimuth and between ?45° and +90° of elevation. Using this technique, the subjects responded 2–8 times more rapidly than previous subjects who used either a verbal-reporting technique or a head-pointing technique. Localization judgments were as accurate as they had been with verbal reports, but were not as accurate as judgments collected using the head-pointing technique. In Experiment 2, the signal was turned off and the experimenter read the spherical coordinates of the signal location to the subjects. The subjects pointed to these coordinates more accurately than they had judged the direction of the sounds in Experiment 1, suggesting that the response technique had not been the limiting factor in that experiment. Circumstances relevant to the choice of response techniques for auditory-localization experiments are discussed.  相似文献   
130.
The inhibition of return of visual attention based on stimulus color was examined in three experiments. In the first experiment, a discrete trial paradigm showed that subjects were slower to detect a color patch if the color matched that of a patch presented earlier in the same location. Experiment 2 showed that the inhibition only occurs if a neutral, nontarget distractor color is presented between presentation of the initial color cue and the subsequent target patch—explaining the previous failures to detect the phenomenon. Experiment 3 extended the results to a different combination of colors. Taken together, the results have important implications for the processing of stimulus attributes such as spatial location and color, and for the conditions necessary for producing inhibition of return.  相似文献   
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