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41.
Some decision analysts recommend reserving their models for careful, complete study of complex problems. Others believe simple problem analyses provide the greatest gains. To clarify these issues, I tested: (1) whether simple published analyses compared to complex ones, produced results as non-intuitive; and (2) whether non-intuitiveness represented analytic gain (or equivalently, intuitive loss). Very limited data also examined (3) the gain from adding model intricacy for a given problem vs. selecting more complex problems for analysis. To assess two non-intuitiveness measures, 75 subjects (33 physicians and 42) non-physicians stated their intuitive preferences in 40 (22 published and 18 unpublished) medical dilemmas. For both physicians and non-physicians, simpler models (those with lees than 30 terminal branches in the decision tree) had about one third the non-intuitiveness of more complex ones. Three tests also supported the premise that analyses outperform intuition, therefore that on average the formers' non-intuitiveness reflects less analytic gain. In addition, for different models of the same problem, tree complexity did not correlate with gain. Thus, simpler trees may not generally gain less because they inadequately describe problems. Instead, simpler analyses may represent simpler problems, with more similar intuitive and formal solutions. If so, these findings may help us avoid some costly but unnecessary simple analyses.  相似文献   
42.
In a two-key concurrent variable-interval schedule (using pigeons), if the reinforcement frequency for one response is held constant while that for the other is increased, the rate of response on the constant key decreases. The immediate reinforcement for key pecking can usually be conceptualized as the change from a condition in which the key light is on and the food hopper light is off to one in which the key light is off and the hopper light is on. The prechange condition is associated with a delay to food of one-half the average interreinforcement interval in effect during this condition. The postchange condition is associated with a delay to food of about .5 seconds. The programming of additional reinforcement results in a decrease in the delay to food associated with the prechange stimulus condition, and thus a decrease in the value of the improvement that results from the change. This would appear to be analogous to a decrease in the amount of reinforcement, and thus sufficient explanation for the decrease in the rate of the response.  相似文献   
43.
Temporal control of behavior and the power law   总被引:9,自引:9,他引:0       下载免费PDF全文
The performance of rats and pigeons under fixed-interval schedules was studied in two experiments. The duration of postreinforcement pause was a declining proportion of fixed-interval duration. For pigeons this was true both when the duration of the reinforcer was fixed and when it was increased in direct proportion to increases in fixed-interval duration; the longer reinforcer durations did, however, lengthen the postreinforcement pause at higher schedule values. A quantitative analysis of data from Experiments 1 and 2 and from other studies showed that fractional exponent power functions described the relationship between postreinforcement pause and fixed-interval value; similar functions have previously been observed in studies of temporal differentiation. It was concluded that power functions reflect a direct causal, rather than artifactual, relationship between performance and the temporal requirements of reinforcement schedules.  相似文献   
44.
In Experiment I, the responding of rats lever pressing on a variable-interval schedule for sucrose solution was partially suppressed by a variable duration conditioned stimulus followed by shock. When food deprivation was increased, response rates during and before the conditioned stimulus increased monotonically. Varying the concentration of sucrose across blocks of sessions or from session to session in a semi-random sequence had little effect on response rates either before or during the conditioned stimulus. With a fixed sequence of increasing concentrations across a five-session block, increased concentration produced much more rapid increases in response rates before than during the conditioned stimulus. In Experiment II, rats were presented with the same sequence of increasing concentrations across a five-session block. When tested at 80% body weight, response rates increased rapidly as concentration increased, but at 100%, body-weight rates increased only slightly. The effect of a change in body weight in Experiment II thus mimicked the effect of the conditioned stimulus in the latter part of Experiment I. These findings support the view that the effect of a pre-aversive conditioned stimulus is similar to that of a change in food deprivation, but unlike that of a change in reinforcement magnitude.  相似文献   
45.
The traditional interpretation of symptom over‐reporting is that it indicates malingering. We explored a different perspective, namely that over‐reporting of eccentric symptoms is related to deficits in articulating internal experiences (i.e., alexithymia). Given that alexithymia has been linked to sleep problems and that fatigue may fuel inattentive responding to symptom lists, we administered measures of alexithymia (TAS ‐20) and symptom over‐reporting (SIMS ), but also sleep quality (SLEEP ‐50) to forensic psychiatric outpatients (n = 40) and non‐forensic participants (n = 40). Forensic patients scored significantly higher on all three indices than non‐forensic participants. In the total sample as well as in subsamples, over‐reporting correlated positively and significantly with alexithymia, with r s being in the 0.50–0.65 range. Sleep problems were also related to over‐reporting, but in the full sample and in the forensic subsample, alexithymia predicted variance in over‐reporting over and above sleep problems. Although our study is cross‐sectional in nature, its results indicate that alexithymia as a potential source of over‐reporting merits systematic research.  相似文献   
46.
Abstract: Joining a vast Wittgensteinian anti‐theoretical movement, John Canfield has argued that it is possible to read the claims that (1) “language is essentially communal” and (2) “it is conceptually possible that a Crusoe isolated from birth should speak or follow rules” in such a way that they are perfectly compatible, and, indeed, that Wittgenstein held them both at once. The key to doing this is to drain them of any theoretical content or implications that would put each claim at odds with the other. I argue here, first of all, that it is not possible to detheorize both (1) and (2) and still hope to say anything illuminating about the nature of language. In fact, Canfield himself does not succeed in detheorizing both (1) and (2) but ends up trivializing (1) and leaving (2) with quite a bit of theoretical content. I further argue, however, that this is getting the matter the wrong way around. Contra Canfield et al., it is only when we recognize this that we can appreciate how radical and innovative Wittgenstein's claims about language really are.  相似文献   
47.
The aim of this paper is to highlight the role of the Decision Support System within the field of multi‐criteria decision aid (MCDA). The MCDA tools have been incorporated into systems to create Multi‐Criteria Decision Support Systems (MCDSSs). In our literature review, we noticed that more than 100 papers have been written over a 20‐year period in which MCDSS was used as a decision‐making tool. The present paper describes some real applications of MCDSS in different fields, harmoniously combined with decision‐making methods such as analytic hierarchy process, Utility Additive, and Goal Programming. The present study proposes an integrative MCDSS evaluation through guidance on the tools most useful for a specific user with a particular decision problem. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
48.
Adam Pryor 《Dialog》2021,60(1):97-102
Responding to the analyses that Andreas Losch and Lucas John Mix offer regarding Living with Tiny Aliens: The Image of God for the Anthropocene, this article begins to address how their respective concerns regarding ratiocentric and anthropocentric ideas haunt the construction of a planetary account of the imago Dei. The article then introduces a subsequent line of critique not mentioned by Losch or Mix related to decentering the human individual from accounts of the imago Dei in order to highlight an ongoing challenge for transdisciplinary theological projects that involve astrobiology.  相似文献   
49.
Initial evidence suggests that gains in relationship functioning from brief, web‐based programs are maintained through one year following the intervention; however, whether these results generalize to a low‐income sample is unclear. Furthermore, previous research from in‐person couple therapy suggests there may be different shapes of maintenance slopes for behavioral versus acceptance‐based techniques. This study contacted 668 individuals who enrolled in online behavioral (ePREP) or acceptance‐based (OurRelationship) programs one year following completion of the program. Multilevel modeling was used to examine linear and quadratic rates of change in the year following the online intervention as well as total amount of change from pretreatment to 12‐month follow‐up for both relationship and individual functioning. The majority of couples who responded continued to be in a relationship with the same partner (68.3%). Examinations of relationship functioning indicated couples in both programs maintained their gains over follow‐up (i.e., no significant linear or quadratic changes), with medium‐to‐large within‐group effect sizes from pre‐ to one‐year follow‐up. There were no significant differences in relationship outcomes between OurRelationship and ePREP. Similarly, examinations of individual functioning outcomes indicated couples maintained their gains over follow‐up or continued to improve. In total, couples experienced small‐to‐medium within‐group effect sizes from pretreatment to one‐year follow‐up, with larger effects for individuals who were initially distressed. These results suggest that online programs create lasting change for low‐income couples in relationship and individual functioning, with minimal differences between behavioral and acceptance‐based orientations.  相似文献   
50.
The purpose of this study was to examine the effects of exposure to political violence on preschool children and their mothers. We explored whether these dyads are different from dyads with no known history of exposure to violence and from mother–child dyads with known exposure to domestic violence. Specifically, we explored differences in mothers' psychological status (depression and anxiety), dyadic emotional availability (EA), children's social information processing, and children's social behaviour, in a sample of 216 dyads divided into three groups (exposure to political violence, no exposure to violence, and exposure to domestic violence). We found evidence to support our hypotheses that children exposed to domestic violence exhibit the highest levels of social maladjustment with smaller but still significant differences between children exposed to political violence and children in the comparison group. As expected, the lowest EA scores were found in the exposure to domestic violence group, followed by dyads in the exposure to political violence group. Dyads belonging to the comparison group (no exposure) exhibited the highest levels of EA. These findings contribute to our understanding of the meaning of exposure to political violence, as well as sharpen the difference between exposure to political and domestic violence.  相似文献   
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