On the empirical indistinguishability of knowledge structures

In recent years a number of articles have focused on the identifiability of the basic local independence model. The identifiability issue usually concerns two model parameter sets predicting an identical probability distribution on the response patterns. Both parameter sets are applied to the same knowledge structure. However, nothing is known about cases where different knowledge structures predict the same probability distribution. This situation is referred to as ʻempirical indistinguishabilityʼ between two structures and is the main subject of the present paper. Empirical indistinguishability is a stronger form of unidentifiability, which involves not only the parameters, but also the structural and combinatorial properties of the model. In particular, as far as knowledge structures are concerned, a consequence of empirical indistinguishability is that the existence of certain knowledge states cannot be empirically established. Most importantly, it is shown that model identifiability cannot guarantee that a certain knowledge structure is empirically distinguishable from others. The theoretical findings are exemplified in a number of different empirical scenarios.     

A Theological Challenge: Coordinating Biological, Social, and Religious Visions of Humanity

This paper attempts two tasks. First, it sketches how the natural sciences (including especially the biological sciences), the social sciences, and the scientific study of religion can be understood to furnish complementary, consonant perspectives on human beings and human groups. This suggests that it is possible to speak of a modern secular interpretation of humanity (MSIH) to which these perspectives contribute (though not without tensions). MSIH is not a comprehensive interpretation of human beings, if only because it adopts a posture of neutrality with regard to the reality of religious objects and the truth of theological claims about them. MSIH is certainly an impressively forceful interpretation, however, and it needs to be reckoned with by any perspective on human life that seeks to insert its truth claims into the arena of public debate. Second, the paper considers two challenges that MSIH poses to specifically theological interpretations of human beings. On the one hand, in spite of its posture of religious neutrality, MSIH is a key element in a class of wider, seemingly antireligious interpretations of humanity, including especially projectionist and illusionist critiques of religion. It is consonance with MSIH that makes these critiques such formidable competitors for traditional theological interpretations of human beings. On the other hand, and taking the religiously neutral posture of MSIH at face value, theological accounts of humanity that seek to coordinate the insights of MSIH with positive religious visions of human life must find ways to overcome or manage such dissonance as arises. The goal of synthesis is defended as important, and strategies for managing these challenges, especially in light of the pluralism of extant philosophical and theological interpretations of human beings, are advocated.     

Process, Content, and Feminist Reflexivity: One Researcher's Exploration

This article explores the unraveling of the relationship between research methodology, process, and content as revealed through my own feminist research project. I examine the evolution of my research process with one participant from a larger study, as I sought to better understand a story she told about racism. First, I address the theoretical underpinnings of feminist reflexivity and research, which challenge traditional paradigms. Next, I present the participant's (a white family day care provider's) story about racism in her practice which was revealed during an interview process. Subsequently, I present a second dialogue around the story in which we (researcher and participant) later engaged. In the process, I analyze my struggles, as a researcher trained in positivist methods, to engage in reflexive research methods. Finally, I evaluate the gains made for me as a researcher in the process and content of research conducted with a feminist reflexive frame and suggest their utility in deconstructing White racism.     

Claudia Card's Concept of Social Death: A New Way of Looking at Genocide

Scholarship in the multidisciplinary field of genocide studies often emphasizes body counts and the number of biological deaths as a way of measuring and comparing the severity and scope of individual genocides. The prevalence of this way of framing genocide is problematic insofar it risks marginalizing the voices and experiences of victims who may not succumb to biological death but nevertheless suffer the loss of family members and other loved ones, and suffer the destruction of relationships, as well as the foundational institutions that give rise to and sustain those relationships. The concept of social death, which Claudia Card offers as the central evil of genocide, marks a radical shift in conceptualizing genocide and provides space for recovering the marginalized voices of many who suffer the evils of genocide but do not suffer biological death. Here her concept of social death is explored, defended, and criticized.     

Predicting positive mental health in internally displaced persons in Indonesia: the roles of economic improvement and exposure to violent conflict

Positive mental health, rather than just the absence of mental illness, is rarely investigated among the internally displaced persons (IDPs) affected by violent conflict in low-income countries. The purpose of this study was to investigate a model that could explain the interrelationship between factors contributing to positive mental health in displaced populations. In a longitudinal study we examine poverty, exposure to traumatic events and the change of material well-being after one year. We collected data in two consecutive years (2005 and 2006) from a community-based sample of IDPs in Ambon, Indonesia, through face-to-face structured interviews with consenting adults. Participants of this study were IDPs lived in Ambon during the violent conflict period. We interviewed 471 IDPs in the first year and reinterviewed 399 (85%) of the same subjects in the second year. The IDPs possessed good sense of coherence and subjective well-being. Our final model, which was generated by the use of structural equation modeling, fits the data well (χ² = 52.51, df = 45, p = .21, CFI = .99, RMSEA = .019). Exposure to violent conflict had a negative impact on IDPs’ mental health initially and better economic conditions improved it (r = ?.30 and .29 respectively). Mental health status one year previously was a strong predictor of future mental health, followed by individual economic growth in the past year (r = .43 and .29 respectively). On a group level the IDPs were resilient and adaptive to survive in adverse living conditions after devastating violent conflict, and the economic improvement contributed to it.     

Sexual Nature? (Re)presenting Sexuality and Science in the Museum

The past 15 years have seen dramatic changes in social norms around sex and sexuality in the UK and worldwide. In 2011, the London Natural History Museum (NHM) contributed to these debates by opening the temporary exhibition Sexual Nature, which aimed to provide ‘a candid exploration of sex in the natural world’ whilst also drawing in an under-represented audience of young adults. Sexual Nature provides an opportunity to explore Macdonald's ‘politics of display’ in the mutual construction of (public) scientific knowledge, society and sexuality, at a time of intense contestation over sexual norms. Whilst Sexual Nature both reflected and contributed to major reframings of sexuality and what science can say about it, the assumption that it would be possible to present this topic as morally neutral, reliable and uncontested, in line with traditions of public science, proved to be problematic. The language of the exhibition moved back and forth between human/animal similarity and difference, and between scientific and cultural tropes as the NHM tried to maintain epistemic authority whilst also negotiating the moral boundaries of acceptable sexual behaviour. The topic of sex pushed the museum far beyond its usual expertise in the natural sciences towards the unfamiliar territory of the social and human, resulting in an ad hoc search for, and negotiation with, alternative sources of expertise. Boon et al.’s co-curation approach to exhibition building has the potential to extend the NHM's audience-driven strategy, whilst also producing a more coherent and nuanced exhibition about the science of sex.     

在综合基础上创新——鼠伤寒菌pla基因及其功能研究的思考

鼠伤寒菌pla基因及功能的研究从课题确立到取得结果整个过程,充分展现了综合研究方法在现代科学研究中的重要作用;在综合基础上的创新是科学研究成功的中心环节。     

Information matrix estimation procedures for cognitive diagnostic models

Two new methods to estimate the asymptotic covariance matrix for marginal maximum likelihood estimation of cognitive diagnosis models (CDMs), the inverse of the observed information matrix and the sandwich-type estimator, are introduced. Unlike several previous covariance matrix estimators, the new methods take into account both the item and structural parameters. The relationships between the observed information matrix, the empirical cross-product information matrix, the sandwich-type covariance matrix and the two approaches proposed by de la Torre (2009, J. Educ. Behav. Stat., 34, 115) are discussed. Simulation results show that, for a correctly specified CDM and Q-matrix or with a slightly misspecified probability model, the observed information matrix and the sandwich-type covariance matrix exhibit good performance with respect to providing consistent standard errors of item parameter estimates. However, with substantial model misspecification only the sandwich-type covariance matrix exhibits robust performance.