Sufficient conditions for uniqueness in Candecomp/Parafac and Indscal with random component matrices

A key feature of the analysis of three-way arrays by Candecomp/Parafac is the essential uniqueness of the trilinear decomposition. We examine the uniqueness of the Candecomp/Parafac and Indscal decompositions. In the latter, the array to be decomposed has symmetric slices. We consider the case where two component matrices are randomly sampled from a continuous distribution, and the third component matrix has full column rank. In this context, we obtain almost sure sufficient uniqueness conditions for the Candecomp/Parafac and Indscal models separately, involving only the order of the three-way array and the number of components in the decomposition. Both uniqueness conditions are closer to necessity than the classical uniqueness condition by Kruskal. Part of this research was supported by (1) the Flemish Government: (a) Research Council K.U. Leuven: GOA-MEFISTO-666, GOA-Ambiorics, (b) F.W.O. project G.0240.99, (c) F.W.O. Research Communities ICCoS and ANMMM, (d) Tournesol project T2004.13; and (2) the Belgian Federal Science Policy Office: IUAP P5/22. Lieven De Lathauwer holds a permanent research position with the French Centre National de la Recherche Scientifique (C.N.R.S.). He also holds an honorary research position with the K.U. Leuven, Leuven, Belgium.     

Degeneracy in Candecomp/Parafac and Indscal Explained For Several Three-Sliced Arrays With A Two-Valued Typical Rank

The Candecomp/Parafac (CP) method decomposes a three-way array into a prespecified number R of rank-1 arrays, by minimizing the sum of squares of the residual array. The practical use of CP is sometimes complicated by the occurrence of so-called degenerate sequences of solutions, in which several rank-1 arrays become highly correlated in all three modes and some elements of the rank-1 arrays become arbitrarily large. We consider the real-valued CP decomposition of all known three-sliced arrays, i.e., of size p×q×3, with a two-valued typical rank. These are the 5×3×3 and 8×4×3 arrays, and the 3×3×4 and 3×3×5 arrays with symmetric 3×3 slices. In the latter two cases, CP is equivalent to the Indscal model. For a typical rank of {m,m+1}, we consider the CP decomposition with R=m of an array of rank m+1. We show that (in most cases) the CP objective function does not have a minimum but an infimum. Moreover, any sequence of feasible CP solutions in which the objective value approaches the infimum will become degenerate. We use the tools developed in Stegeman (2006), who considers p×p×2 arrays, and present a framework of analysis which is of use to the future study of CP degeneracy related to a two-valued typical rank. Moreover, our examples show that CP uniqueness is not necessary for degenerate solutions to occur. The author is supported by the Dutch Organisation for Scientific Research (NWO), VENI grant 451-04-102.     

创造性思维之类比法在医学研究中的应用——论红细胞免疫系统假说的提出

文章阐述了创造性思维之类比法在红细胞免疫系统假说提出及完善中发挥的作用,表明培养学生的创造性思维,在医学实践观察、理论研究及临床思维中是极为重要的。使我们认识到,医学认识目的的实现,需要创造和使用某种适当的认识手段。     

Socially Situated Transmission: The Bias to Transmit Negative Information is Moderated by the Social Context

Cultural evolutionary theory has identified a range of cognitive biases that guide human social learning. Naturalistic and experimental studies indicate transmission biases favoring negative and positive information. To address these conflicting findings, the present study takes a socially situated view of information transmission, which predicts that bias expression will depend on the social context. We report a large-scale experiment (N = 425) that manipulated the social context and examined its effect on the transmission of the positive and negative information contained in a narrative text. In each social context, information was progressively lost as it was transmitted from person to person, but negative information survived better than positive information, supporting a negative transmission bias. Importantly, the negative transmission bias was moderated by the social context: Higher social connectivity weakened the bias to transmit negative information, supporting a socially situated account of information transmission. Our findings indicate that our evolved cognitive preferences can be moderated by our social goals.     

The role of the nucleus accumbens in knowing when to respond

While knowing what to expect is important, it is equally important to know when to expect it and to respond accordingly. This is apparent even in simple Pavlovian training situations in which animals learn to respond more strongly closer to reward delivery. Here we report that the nucleus accumbens core, an area well-positioned to represent information about the timing of impending rewards, plays a critical role in this timing function.     

Using the regulation of accuracy to study performance when the correct answer is not known

We examined memory performance in multiple‐choice questions when correct answers were not always present. How do participants answer when they are aware that the correct alternative may not be present? To answer this question we allowed participants to decide on the number of alternatives in their final answer (the plurality option), and whether they wanted to report or withhold their answer (report option). We also studied the memory benefits when both the plurality and the report options were available. In two experiments participants watched a crime and then answered questions with five alternatives. Half of the questions were presented with the correct alternative and half were not. Participants selected one alternative and rated confidence, then selected three alternatives and again rated confidence, and finally indicated whether they preferred the answer with one or with three alternatives (plurality option). Lastly, they decided whether to report or withhold the answer (report option). Results showed that participants’ confidence in their selections was higher, that they chose more single answers, and that they preferred to report more often when the correct alternative was presented. We also attempted to classify a posteriori questions as either presented with or without the correct alternative from participants’ selection. Classification was better than chance, and encouraging, but the forensic application of the classification technique is still limited since there was a large percentage of responses that were incorrectly classified. Our results also showed that the memory benefits of both plurality and report options overlap.     

The contribution of familiarity to recognition memory is a function of test format when using similar foils

Patient Y.R., who suffered hippocampal damage that disrupted recollection but not familiarity, was impaired on a yes/no (YN) object recognition memory test with similar foils. However, she was not impaired on a forced-choice corresponding (FCC) version of the test that paired targets with corresponding similar foils (Holdstock et al., 2002). This dissociation is explained by the Complementary Learning Systems (CLS) neural-network model (Norman & O'Reilly, 2003) if recollection is impaired but familiarity is preserved. The CLS model also predicts that participants relying exclusively on familiarity should be impaired on forced-choice noncorresponding (FCNC) tests, where targets are presented with foils similar to other targets. The present study tests these predictions for all three test formats (YN, FCC, FCNC) in normal participants using two variants of the remember/know procedure. As predicted, performance using familiarity alone was significantly worse than standard recognition on the YN and FCNC tests, but not on the FCC test. Recollection in the form of recall-to-reject was the major process driving YN recognition. This adds support to the interpretation of patient data, according to which hippocampal damage causes a recollection deficit that leads to poor performance on the YN test relative to FCC.     

Self-esteem predicts quality of responding to interview questions when skill in responding is low

Self-esteem, skill in responding, and skill appraisals have each been posited to influence the quality of information gathered during interviews about witnessed events. This study examined whether self-esteem exacerbates or buffers skill related deficits and awareness of skill. Participants viewed a video, completed measures of self-esteem, estimated their skill in responding, responded to answerable and unanswerable questions about the video, and re-estimated their skill. Skill was indexed as effectiveness in resisting unanswerable questions. Moderated regression analyses showed that high self-esteem was associated with higher accuracy and fewer errors to answerable questions, but only when skill was low. Low skill individuals overestimated their ability. Following practice, low skill individuals with low trait self-esteem recalibrated their skill appraisals, while low skill high self-esteem individuals did not become aware of their lack of skill. When skill was high, self-esteem was not related to responding. Understanding the influence of self-esteem on the quality of information gathered during interviews about witnessed events requires attention to interactions with skill and performance appraisals.     

散文学习过程中自我解释的实验研究

自我解释已经为许多研究所证实,但是多数研究使用的都是自然学科的内容作为实验材料,探讨散文学习过程中自我解释的研究较少.因此,本研究引入组别变量,自我解释对散文学习的影响.结果发现:(1)自我解释对散文学习产生了影响,对散文的阅读理解具有促进作用;(2)自我解释对散文学习产生影响机制可能是认知缺口填补和心理模型修正(3)自我解释是可以学习和迁移的,并且其中提供的反馈有助于提升自我解释的准确性.     

The Proof is in the Punch: Gender Differences in Perceptions of Action and Aggression as Components of Manhood

Two studies test the hypotheses that men, relative to women: 1) see manhood as a more elusive, impermanent state than womanhood, and 2) understand aggression as a means of proving or re-establishing threatened manhood, but not threatened womanhood. In Study 1 (N?=?175 Northeastern U.S. undergraduates), men’s (but not women’s) sentence completions revealed tendencies to define manhood by actions and womanhood by enduring traits. In Study 2 (N?=?113 Southeastern U.S. undergraduates), men were more likely than women to explain a man’s physical aggression in primarily situational terms, whereas men and women did not differ in the attributions they made for a woman’s physical aggression. Results suggest that men perceive active and aggressive behaviors as integral parts of manhood and its defense.     

The Orthodox Understanding of Marriage in the Ecumenical Context

This article deals with interchurch and interreligious marriage as a challenge to Orthodox theology and its self-conscience. The canons of the church came into being at a time when the church identified itself with history, and the Empire with the kingdom of God. Their purpose was to strengthen the historical construction of the church and the Empire. In such a context, the “other” was a threat to the historical existence of the church. Eschatology offers a different perspective, seeing the whole world as a church “in becoming.” Mixed marriages pose the following questions: How do we understand ourselves? How do we understand others? Our tradition has been challenged with new events and new realities, demanding bravery to solve them.     

The Rorschach in the Context of Performance-Based Personality Assessment

Twenty-eight normal and 28 learning disabled children were given the Bender-Gestalt Test under instructional sets of low (standard) attention or high attention. Results failed to support the hypothesis that high attention instructions would lead to differential recall performance of the diagnostic groups. Normal children produced better designs during recall than learning disabled children regardless of instructional set. The evidence suggests that standard Bender instructions should not be altered in an attempt to elicit recall performance differences.     

“Icing the shooter” in basketball: The unintended consequences of time-out management when the game is on the line

While the sport of basketball is usually characterized by a non-segmented and mostly uninterrupted play, the stoppage of the time due to time-outs (TOs) is widespread when the game is on the line. In the current investigation, we studied the effects of TOs on free-throw performance when NCAA (National Collegiate Athletic Association) games were close and time was winding down (n = 99,026 combined sample). We generally found that time extension before execution undermined performance but not in the last minute of play when performance deteriorated altogether. In line, traditional icing when TOs were called by opposing coaches specifically to undermine performance in the last minute of play failed to exact the intended goal of lowering free-throw performance.     

生命伦理学语境下黑格尔《精神现象学》的生命向度阐释

黑格尔的<精神现象学>在某种意义上亦可作为一种生命哲学和生命伦理学,它所阐明的精神运动的各个环节都饱含着对于生命的深度关切,毋宁说,<精神现象学>本身就是一种生命的精神表征,由此这种生命向度在其构筑的精神体系之中成为内在的伦理价值旨趣.在生命哲学与生命伦理学的语境下阐释<精神现象学>的生命向度,指明生命在时间和空间维度中的各个环节及其辩证运动过程,可为当下生命伦理精神的构建提供一种可能的哲学基础和精神质料.     

The Witness to Witness Program: Helping the Helpers in the Context of the COVID-19 Pandemic

The Witness to Witness Program (W2W), based on Weingarten’s witnessing model (2000, 2003, 2004), began in July 2018 and originally was established to support healthcare workers and attorneys (our partners) who were experiencing empathic distress working with people involved in various stages of the detention process. The W2W program evolved to offer four primary components: clinician listening sessions geared to deep understanding of the person’s story of their work and its challenges; an inventory of the person’s current internal and external resources both in the present and in the past; help with removal of barriers to those resources; and development of a personal toolkit to handle stress. Additional services available to partners and their organizations included psycho-educational webinars, facilitated peer support groups, and organizational consultations to foster trauma-sensitive and resilience-hardy work environments. In March, after lockdowns due to the coronavirus pandemic, W2W pivoted to focus on handouts and webinars addressing how to cope with distress and moral injury, maintaining resilience, coping with grief, and dealing with multiple losses caused by the pandemic. Disaster sparked collaboration and innovation. A train the trainer model was developed to reach more community health workers providing services to the Latinx community dealing with losses similar to those experienced by the clients they serve. W2W continues to create virtual communities of support. In doing so we practice doing reasonable hope together (Weingarten, Family Process, 2010, 49, 5).     

The semantic specificity of gestures when verbal communication is not possible: The case of emergency evacuation

The aim of the present study was to examine the comprehension of gesture in a situation in which the communicator cannot (or can only with difficulty) use verbal communication. Based on theoretical considerations, we expected to obtain higher semantic comprehension for emblems (gestures with a direct verbal definition or translation that is well known by all members of a group, or culture) compared to illustrators (gestures regarded as spontaneous and idiosyncratic and that do not have a conventional definition). Based on the extant literature, we predicted higher semantic specificity associated with arbitrarily coded and iconically coded emblems compared to intrinsically coded illustrators. Using a scenario of emergency evacuation, we tested the difference in semantic specificity between different categories of gestures. 138 participants saw 10 videos each illustrating a gesture performed by a firefighter. They were requested to imagine themselves in a dangerous situation and to report the meaning associated with each gesture. The results showed that intrinsically coded illustrators were more successfully understood than arbitrarily coded emblems, probably because the meaning of intrinsically coded illustrators is immediately comprehensible without recourse to symbolic interpretation. Furthermore, there was no significant difference between the comprehension of iconically coded emblems and that of both arbitrarily coded emblems and intrinsically coded illustrators. It seems that the difference between the latter two types of gestures was supported by their difference in semantic specificity, although in a direction opposite to that predicted. These results are in line with those of Hadar and Pinchas‐Zamir (2004), which showed that iconic gestures have higher semantic specificity than conventional gestures.     

Holistic representation of negative numbers is formed when needed for the task

Past research suggested that negative numbers are represented in terms of their components—the polarity marker and the number (e.g., Fischer & Rottmann, 2005 Fischer, M. and Rottmann, J. 2005. Do negative numbers have a place on the mental number line?. Psychology Science, 47(1): 22–32.  [Google Scholar]; Ganor-Stern & Tzelgov, 2008 Ganor-Stern, D. and Tzelgov, J. 2008. Negative numbers are generated in the mind. Experimental Psychology, 55(3): 157–163.  [Google Scholar]). The present study shows that a holistic representation is formed when needed for the task requirement. Specifically, performing the numerical comparison task on positive and negative numbers presented sequentially required participants to hold both the polarity and the number magnitude in memory. Such a condition resulted in a holistic representation of negative numbers, as indicated by the distance and semantic congruity effects. This holistic representation was added to the initial components representation, thus producing a hybrid holistic-components representation.