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71.
The fixed point combinator (Y) is an important non-proper combinator, which is defhable from a combinatorially complete base. This combinator guarantees
that recursive equations have a solution. Structurally free logics (LC) turn combinators into formulas and replace structural rules by combinatory ones. This paper introduces the fixed point and
the dual fixed point combinator into structurally free logics. The admissibility of (multiple) cut in the resulting calculus is not provable by a simple adaptation of the similar proof for LC with proper combinators. The novelty of our proof—beyond proving the cut for a newly extended calculus–is that we add a fourth induction to the by-and-large Gentzen-style proof.
Presented by Robert Goldblatt 相似文献
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74.
We evaluated an outcome management program for increasing choice opportunities provided by 2 job coaches for 5 supported workers with severe multiple disabilities in a community job. The program involved specifying and monitoring behavioral outcomes among workers and staff, training staff, and supportive and corrective feedback. Increased choice provision occurred for both job coaches across a 1-year period. Results indicate how outcome management can help translate advances in choice research into routine practice. 相似文献
75.
The effects of manipulations of response requirement, intertrial interval (ITI), and psychoactive drugs (ethanol, phencyclidine, and d-amphetamine) on lever choice under concurrent fixed-ratio schedules were investigated in rats. Responding on the "certain' lever produced three 45-mg pellets, whereas responding on the "risky" lever produced either 15 pellets (p = .33) or no pellets (p .67). Rats earned all food during the session, which ended after 12 forced trials and 93 choice trials or 90 min, whichever occurred first. When the response requirement was increased from 1 to 16 and the ITI was 20 s, percentage of risky choice was inversely related to fixed-ratio value. When only a single response was required but the ITI was manipulated between 20 and 120 s (with maximum session duration held constant), percentage of risky choice was directly related to length of the ITI. The effects of the drugs were investigated first at an ITI of 20 s, when risky choice was low for most rats, and then at an ITI of 80 s, when risky choice was higher for most rats. Ethanol usually decreased risky choice. Phencyclidine did not usually affect risky choice when the ITI was 20 s but decreased it in half the rats when the ITI was 80 s. For d-amphetamine, the effects appeared to he related to baseline probability of risky choice; that is, low probabilities were increased and high probabilities were decreased. Although increase in risky choice as a function of the ITI is at variance with previous ITI data, it is consistent with foraging data showing that risk aversion decreases as food availability decreases. The pharmacological manipulations showed that drug effects on risky choice may be influenced by the baseline probability of risky choice, just as drug effects can be a function of baseline response rate. 相似文献
76.
基于等级反应模型的规则空间方法 总被引:1,自引:0,他引:1
本研究基于Tatsuoka的规则空间方法, 对理想反应模式与异常反应指标进行了扩展, 推导了多级评分项目下规则空间方法的算法公式。在4种属性层级结构(发散型、收敛型、线型与无结构型)×4种“失误”作答概率(2%、5%、10%与15%)测验情境下, 以属性模式判准率、被试属性判准率、敏感性与特异性为指标, 检验了多级评分项目下规则空间方法的分类准确性。结果表明:(1) 基于多级评分项目构建的异常反应指标, 能有效地对被试进行分类与解释, 且0-1评分项目下异常反应指标及其性质都是多级评分下的特例; (2) 随着“失误”作答概率的增加, 4种属性层级结构的分类准确性都会降低; (3) 线型和收敛型的分类准确性明显好于发散型与无结构型; (4) 纯规则点的分布对规则空间方法的分类准确性有显著影响。 相似文献
77.
Rita Chiesa Fabio Massei Dina Guglielmi 《Journal of counseling and development : JCD》2016,94(2):210-224
The authors explored the effects of a structured‐group career intervention among 280 Italian high school students. Hierarchical linear models indicated the intervention's effectiveness in increasing career decision‐making self‐efficacy and, consequently, career exploration, but not in decreasing career choice anxiety. In addition, partial confirmation was found for the moderating effects of participants' expectations and motivation to change on the relationship between career decision‐making self‐efficacy and career choice anxiety. The findings support the development of a systematic vocational guidance program in Italian schools. 相似文献
78.
This study examined the relationship between physical contact and decision type in predicting “harm to save” behavior. Participants were assigned to making either a judgment or a choice involving moral dilemmas. All participants were presented with dilemmas that either required or did not require having physical contact with potential victims. Participants were asked to decide whether to sacrifice fewer people to save more (utilitarian responses) or not to do so and thus more people would die (deontological responses). The study sample included 345 participants who completed a set of self‐report measures. Results indicated an interaction between physical contact and decision type. In the choice condition only, participants reported significantly less utilitarian responses to the dilemmas that required having physical contact with the person to be harmed than to dilemmas that did not require physical contact. This difference was not found in the judgment condition. These results contribute to a greater understanding of the nature and potential malleability of human morality. 相似文献
79.
Previous research on preference between variable-interval terminal links in concurrent chains has most often used variable-duration terminal links ending with a single reinforcer. By contrast, most research on resistance to change in multiple schedules has used constant-duration components that include variable numbers of reinforcers in each presentation. Grace and Nevin (1997) examined both preference and resistance in variable-duration components; here, preference and resistance were examined in constant-duration components. Reinforcer rates were varied across eight conditions, and a generalized-matching-law analysis showed that initial-link preference strongly over-matched terminal-link reinforcer ratios. In multiple schedules, baseline response rates were unaffected by reinforcer rates, but resistance to intercomponent food, to extinction, and to intercomponent food plus extinction was greater in the richer component. The between-component difference in resistance to change exhibited additive effects for the three resistance tests, and was systematically related to reinforcer ratios. However, resistance was less sensitive to reinforcer ratios than was preference. Resistance to intercomponent food and to intercomponent food plus extinction was more sensitive to reinforcer ratios in the present study than in Grace and Nevin (1997). Thus, relative to variable-duration components, constant-duration components increased the sensitivity of both preference and relative resistance, supporting the proposition that these are independent and convergent measures of the effects of a history of reinforcement. 相似文献
80.
David S. Chester Sarah Beth Bell C. Nathan DeWall Samuel J. West Marisabel Romero-Lopez Adam W. Craig 《Aggressive behavior》2019,45(5):507-516
People often have to make decisions between immediate rewards and more long-term goals. Such intertemporal judgments are often investigated in the context of monetary choice or drug use, yet not in regard to aggressive behavior. We combined a novel intertemporal aggression paradigm with functional neuroimaging to examine the role of temporal delay in aggressive behavior and the neural correlates thereof. Sixty-one participants (aged 18–22 years; 37 females) exhibited substantial variability in the extent to which they selected immediate acts of lesser aggression versus delayed acts of greater aggression against a same-sex opponent. Choosing delayed-yet-more-severe aggression was increased by provocation and associated with greater self-control. Preferences for delayed aggression were associated with greater activity in the ventromedial prefrontal cortex (VMPFC) during such choices, and reduced functional connectivity between the VMPFC and brain regions implicated in motor impulsivity. Preferences for immediate aggression were associated with reduced functional connectivity between the VMPFC and the frontoparietal control network. Dispositionally aggressive participants exhibited reduced VMPFC activity, which partially explained and suppressed their preferences for delayed aggression. Blunted VMPFC activity may thus be a neural mechanism that promotes reactive aggression towards provocateurs among dispositionally aggressive individuals. These findings demonstrate the utility of an intertemporal framework for investigating aggression and provide further evidence for the similar underlying neurobiology between aggression and other rewarding behaviors. 相似文献