Sharvy’s Lucy and Benjamin Puzzle

Sharvy’s puzzle concerns a situation in which common knowledge of two parties is obtained by repeated observation each of the other, no fixed point being reached in finite time. Can a fixed point be reached?     

Reference point adaptation: Tests in the domain of security trading

According to prospect theory [Kahneman, D., & Tversky, A. (1979). Prospect theory: An analysis of decision under risk, Econometrica, 47, 263–292], gains and losses are measured from a reference point. We attempted to ascertain to what extent the reference point shifts following gains or losses. In questionnaire studies, we asked subjects what stock price today will generate the same utility as a previous change in a stock price. From participants’ responses, we calculated the magnitude of reference point adaptation, which was significantly greater following a gain than following a loss of equivalent size. We also found the asymmetric adaptation of gains and losses persisted when a stock was included within a portfolio rather than being considered individually. In studies using financial incentives within the BDM procedure [Becker, G. M., DeGroot, M. H., & Marschak, J. (1964). Measuring utility by a single-response sequential method. Behavioral Science, 9(3), 226–232], we again noted faster adaptation of the reference point to gains than losses. We related our findings to several aspects of asset pricing and investor behavior.     

科学研究始于机会,还是始于问题或观察?

With the recent rise of the philosophy of scientific practices, SSK (Sociology of Scientific Knowledge), and feminist approaches to the philosophy of science, a new perspective is gradually coming into being, holding that the starting point for scientific research is opportunity. Opportunistic features in solar neutrino experiments, Opportunistic features of complexity studies emerging from economics, and the measurement of insects’ flight can prove the above perspective from different angels. It is important and significant to determine whether the starting point for scientific research is opportunity, a problem, or an observation. Translated by Tian Xiaofei from Zhexue Yanjiu 哲学研究 (Philosophical Research), 2007, (1): 98–104     

风险决策中的双参照点效应

以预期理论为代表的决策理论认为, 决策者自身的损益状态对风险决策有重要作用, 因此, 将决策者的现状定义为个人参照点。它决定了决策情境是个人获益还是个人损失。个人参照点直接关乎决策者实际的得失, 具有直接性、真实性和绝对性的特征。然而, 社会比较理论认为, 与他人的比较结果同样对风险决策具有不可忽视的意义。因此, 将他人的状态定义为社会参照点。自身的现状与他人状态相比较的结果决定了决策情境是社会获益还是社会损失。社会参照点无关决策者的实际得失, 具有间接性、假设性和相对性的特征。社会参照点通过自我概念、情绪、认知等路径作用于风险决策。更为重要的是, 社会参照点和个人参照点同时存在于风险决策过程中, 决策者对两者的心理感受和行为倾向具有相似性, 因此两者将共同影响决策者的风险选择。基于此, 本文提出风险决策中的双参照点效应。有关双参照点对风险决策过程的影响机制还需进一步的探讨。     

知识点认知规律的实验研究

知识点是人的认知单位,人学习知识,必须以知识点为单位、逐个知识点地学习。本实验以概念学习为例,研究了人一次学习一个知识点与同时学习两个知识点时的成绩差异。研究结果表明,1. 在概念中的信息组块数不超过短时记忆容量的前提下,一次学习一个概念,构成概念的信息组块数对概念掌握影响不显著。2.在同样条件下,一次学习一个知识点的成绩好于同时学习两个知识点的成绩,从而验证了知识点认知规律。     

无性生育的伦理考量

从有性生育到无性生育,这是人类生育方式的重大变革。无性生育是从细胞水平上对人类生育方式的干预。无性生育技术的出现及其实验,并不意味“人类的自然生育方式将要终结”,它只是有性生育的必要补充。无性生育技术的滥用和无性生育的泛滥有可能导致人类尊严的彻底丧失和以人的尊严为基础的人类明的倒退。对无性生育技术的研究和应用必须实施社会控制。     

Body language reading of emotion in schizophrenia: Associations with symptoms and functional outcome

Our aim was to explore how body language reading of emotion relates to neurocognition, symptoms and functional outcome in schizophrenia. Fifty‐four individuals with schizophrenia and eighty‐four healthy controls participated in the study. Emotion perception was assessed with a point‐light display (PLD) task, the Emotion in Biological Motion (EmoBio) test, neurocognition was measured with the MATRICS Consensus Cognitive Battery (MCCB), and functioning was indexed by one measure of functional capacity and by one self‐report questionnaire. Clinical symptoms were assessed with a five factor Positive and Negative Syndrome Scale (PANSS) symptoms model. Participants with schizophrenia had impaired body language reading of emotions compared to healthy controls (Cohen's d = 0.69). In participants with schizophrenia, emotion perception was associated with neurocognition (r = 0.42), functional capacity (r = 0.27) and disorganization symptoms (r = –0.27). Mediation analyses showed that disorganization symptoms mediated the effects of emotion perception and neurocognition, respectively, on social functional capacity. These results suggest that in individuals with schizophrenia, reduced emotion perception from body movements has negative consequences for functional outcome, but that the effect is mediated through disorganization symptoms.     

Melting point depression method for determining the solid–liquid interfacial energy of metal elements: theoretical validation and updated compilation of data

Comparative analyses of the crystal nucleation method and the melting point depression (MPD) method for measuring the solid–liquid interface energy γ_sl are carried out. The MPD method is found more reliable and has several advantages from experiment through data analysis to theoretical generalisation. The MPD data in use, all reported before the 1970s, are updated with the derived γ_sl re-compiled. Finally, by invoking a melting model that we developed recently, an equation for calculating γ_sl is proposed on basis of the melting point depression method.     

Switching memory perspective

The perspective in which memories were spontaneously recalled, field (original perspective) or observer (see oneself in the memory), was examined for both recent and remote memories. Recent memories were dominated by field perspective whilst remote memories were dominated by observer perspective. Further, field memories contained reliably more episodic detail than observer memories. After a 1-week interval, the same memories were recalled again but with a switched memory perspective. Switching from an observer to a field perspective did not reliably increase the amount of episodic details in a memory. Switching from field to observer perspective did, however, reliably reduce the number of episodic details. These findings suggest that memories may be represented in long-term memory with a fixed perspective, either field or observer, which can be temporarily altered sometimes changing the nature of a memory, i.e. how much detail remains accessible.     

Pupillometry reveals communication‐induced object expectations in 12‐ but not 8‐month‐old infants

Several interaction‐based and looking‐time studies suggest that 1‐year‐old infants understand the referential nature of deictic gestures. However, these studies have not unequivocally established that referential gestures induce object expectations in infants prior to encountering a referent object, and have thus remained amenable to simpler attentional highlighting interpretations. The current study tested whether nonlinguistic referential communication induces object expectations in infants by using a novel pupil dilation paradigm. In Experiment 1, 12‐month‐olds watched videos of a protagonist who either pointed communicatively toward an occluder in front of her or remained still. At test, the occluder opened to reveal one of two outcomes: an empty surface or a toy. Results showed that infants’ pupils were larger for the unexpected outcome of an empty surface following a point compared to the control condition (an empty surface following no point). These differences were not caused by differences in looking times or directions. In Experiment 2, an attention‐directing nonsocial control cue replaced the referential communication. The cue did direct 12‐month‐olds’ attention to the occluder, but it did not induce an object expectation. In Experiment 3, we tested 8‐month‐olds in the setting of Experiment 1. In contrast to 12‐month‐olds, 8‐month‐olds did not reveal object expectations following communication. Findings demonstrate that communicative pointing acts induce object expectations at 12 months of age, but not at 8 months of age, and that these expectations are specific to a referential‐communicative as opposed to an attention‐directing nonsocial cue.