Incomplete List Research Articles

A hidden ambiguity of the term "feedback" in its use as an explanatory mechanism for psychophysical visual phenomena.

Over the last decades many researchers have used concepts like “feedback,” “reentrance,” “backpropagation,” “top–down (modulation),” or “reverse hierarchy” to specify the mechanisms that underlie various visual phenomena (e.g., Di Lollo et al., 2000; Lamme and Roelfsema, 2000; Pascual-Leone and Walsh, 2001; Super et al., 2001; Ro et al., 2003; Ahissar and Hochstein, 2004; Bar et al., 2006; Fahrenfort et al., 2007; Koivisto, 2012). An incomplete list of these phenomena includes visual (object substitution) masking, shape discrimination, illusory contours, illusory motion, priming effects, etc. Empirical evidence or theoretical argumentation in favor of the suggested mechanismic explanations mainly consists in finding or postulating an association between a temporally delayed, secondary activition of lower level neural units with correct reports of target stimuli, even though the higher level neural units in the processing hierarchy were already activated earlier. On that basis, feedforward processing has been argued to be insufficient for target perception. However, in most of the studies the relative temporal order of activity at different levels alone is taken as proof of reentrant modulation without precisely measuring the neural sources of this top–down effect. In principle, it is equally possible that the source of the higher level activity from which the top–down signals are sent back to earlier feature-encoding neural units (i) is specifically linked to those features by virtue of constituting the higher level nodes associated with specific attributes of the target stimulus (thus mediating feature-binding for object integration) or (ii) is not specifically linked in this manner. In the latter case, the source of top–down modulation may be the result of the arousal or alerting boost triggered by the target stimulus via feedforward collateral activation of subcortical reticulo-thalamic units, which in turn is followed by the cortical spread of the thalamocortical activation, including the downpropagation of the non-specific wave of modulation to the early cortical areas. The non-specific system functions include arousal, attentional modulation, intercortical synchronization of neural activity, bringing the preconsciously processed specific content to awareness, “event-holding” the content in working memory, and alerting subjects to newly appearing objects and changes (Magoun, 1958; Purpura, 1970; Purpura and Schiff, 1997; Jones, 2001; Llinas and Ribary, 2001; Van der Werf et al., 2002; Ribary, 2005; Schiff et al., 2013; Saalmann, 2014). This non-specific system (NSP) targets layer-1 apical dendrites of the layer-5 and -6 pyramidal neurons. But since NSP-modulation is directed at the cortical neurons with specific representational functions, its function may go unacknowledged because the cortical units, when activated by NSP-modulation, can produce content-specific subjective effects misleading us to believe that the entire process has been specific throughout.

Corrections to “Effects of the Simultaneous Presence of Static Eccentricity and Broken Rotor Bars on the Stator Current of Induction Machine” [May 14 2452-2463

Due to an unfortunate omission, the above paper (ibid., vol. 61, no. 5, pp. 2452-2463, May 2014), was submitted and published with an incomplete list of authors. The full list of the authors of this paper is Mohamed Yazid Kaikaa, Marouane Hadjami, and Abdelmalek Khezzar. The third author, whose name was omitted from the original paper, is with the Laboratoire d'Electrotechnique de Constantine, Mentouri University of Constantine, 25000 Constantine, Algeria (e-mail: akhezzar@yahoo.fr). The photograph and biography of Prof. Khezzar are presented here.

Evolutionary conservation in genes underlying human psychiatric disorders.

Many psychiatric diseases observed in humans have tenuous or absent analogs in other species. Most notable among these are schizophrenia and autism. One hypothesis has posited that these diseases have arisen as a consequence of human brain evolution, for example, that the same processes that led to advances in cognition, language, and executive function also resulted in novel diseases in humans when dysfunctional. Here, the molecular evolution of the protein-coding regions of genes associated with these and other psychiatric disorders are compared among species. Genes associated with psychiatric disorders are drawn from the literature and orthologous sequences are collected from eleven primate species (human, chimpanzee, bonobo, gorilla, orangutan, gibbon, macaque, baboon, marmoset, squirrel monkey, and galago) and 34 non-primate mammalian species. Evolutionary parameters, including dN/dS, are calculated for each gene and compared between disease classes and among species, focusing on humans and primates compared to other mammals, and on large-brained taxa (cetaceans, rhinoceros, walrus, bear, and elephant) compared to their small-brained sister species. Evidence of differential selection in humans to the exclusion of non-human primates was absent, however elevated dN/dS was detected in catarrhines as a whole, as well as in cetaceans, possibly as part of a more general trend. Although this may suggest that protein changes associated with schizophrenia and autism are not a cost of the higher brain function found in humans, it may also point to insufficiencies in the study of these diseases including incomplete or inaccurate gene association lists and/or a greater role of regulatory changes or copy number variation. Through this work a better understanding of the molecular evolution of the human brain, the pathophysiology of disease, and the genetic basis of human psychiatric disease is gained.

Stability of bivariate GWAS biomarker detection.

Given the difficulty and effort required to confirm candidate causal SNPs detected in genome-wide association studies (GWAS), there is no practical way to definitively filter false positives. Recent advances in algorithmics and statistics have enabled repeated exhaustive search for bivariate features in a practical amount of time using standard computational resources, allowing us to use cross-validation to evaluate the stability. We performed 10 trials of 2-fold cross-validation of exhaustive bivariate analysis on seven Wellcome–Trust Case–Control Consortium GWAS datasets, comparing the traditional test for association, the high-performance GBOOST method and the recently proposed GSS statistic (Available at http://bioinformatics.research.nicta.com.au/software/gwis/). We use Spearman's correlation to measure the similarity between the folds of cross validation. To compare incomplete lists of ranks we propose an extension to Spearman's correlation. The extension allows us to consider a natural threshold for feature selection where the correlation is zero.This is the first reported cross-validation study of exhaustive bivariate GWAS feature selection. We found that stability between ranked lists from different cross-validation folds was higher for GSS in the majority of diseases. A thorough analysis of the correlation between SNP-frequency and univariate score demonstrated that the test for association is highly confounded by main effects: SNPs with high univariate significance replicably dominate the ranked results. We show that removal of the univariately significant SNPs improves replicability but risks filtering pairs involving SNPs with univariate effects. We empirically confirm that the stability of GSS and GBOOST were not affected by removal of univariately significant SNPs.These results suggest that the GSS and GBOOST tests are successfully targeting bivariate association with phenotype and that GSS is able to reliably detect a larger set of SNP-pairs than GBOOST in the majority of the data we analysed. However, the test for association was confounded by main effects.

Influence of plastids on light signalling and development.

In addition to their contribution to metabolism, chloroplasts emit signals that influence the expression of nuclear genes that contribute to numerous plastidic and extraplastidic processes. Plastid-to-nucleus signalling optimizes chloroplast function, regulates growth and development, and affects responses to environmental cues. An incomplete list of plastid signals is available and particular plastid-to-nucleus signalling mechanisms are partially understood. The plastid-to-nucleus signalling that depends on the GENOMES UNCOUPLED (GUN) genes couples the expression of nuclear genes to the functional state of the chloroplast. Analyses of gun mutants provided insight into the mechanisms and biological functions of plastid-to-nucleus signalling. GUN genes contribute to chloroplast biogenesis, the circadian rhythm, stress tolerance, light signalling and development. Some have criticized the gun mutant screen for employing inhibitors of chloroplast biogenesis and suggested that gun alleles do not disrupt significant plastid-to-nucleus signalling mechanisms. Here, I briefly review GUN-dependent plastid-to-nucleus signalling, explain the flaws in the major criticisms of the gun mutant screen and review the influence of plastids on light signalling and development.

Assessing Student Pharmacists’ Ability to Identify Drug-Related Problems in Patients Within a Patient-Centered Medical Home

To quantify, describe, and categorize patient drug-related problems (DRPs) and recommendations identified by fourth-year (P4) student pharmacists during a live medication reconciliation activity within a patient-centered medical home (PCMH). Fourth-year student pharmacists conducted chart reviews, identified and documented DRPs, obtained live medication histories, and immediately provided findings and recommendations to the attending physicians. Documentation of DRPs and recommendations were analyzed retrospectively. Thirty-eight students completed 99 medication reconciliation sessions from June 2011 to October 2012 during their advanced pharmacy practice experience (APPE). The students obtained 676 patient medication histories and identified or intervened on 1308 DRPs. The most common DRPs reported were incomplete medication list and diagnostic/laboratory testing needed. Physicians accepted 1,018 (approximately 78%) recommendations. Student pharmacists successfully identified and reduced DRPs through a live medication reconciliation process within an academic-based PCMH model. Their medication history-taking skills improved and medication use was optimized.

Eles eram muitos cavalos : Challenging the Regulating Fiction of the Global City

PUBLISHED in 2001, Eles eram muitos cavalos by Luiz Ruffato has been critically acclaimed as one of the most important novels in contemporary Brazilian literature. Having won the 2001 Machado de Assis award from Biblioteca Nacional and been selected as best novel by the Associacao Paulista de Criticos de Arte in the same year, Eles eram muitos cavalos received in 2005 fourth place among the most important 125 works of Brazilian fiction to be published since 1990. Taking place in Sao Paulo on May 9, 2000, the novel narrates a single day in the lives of people living in the city. Numerous anonymous characters are the protagonists of multiple stories that read as entries more than as chapters, which do not build up as a connected longer narrative. Hence, the continuous shift in narrative voice and perspective announces various experiences that travel across class, gender, and race, ultimately unfolding a conjuncture of extreme social inequality. Most of the excitement around Eles eram muitos cavalos in the years following its publication celebrated the novel's narrative style and format, namely its realist narrative approach as well as the unusual use of layout and grammatical experimentation. The realist style can be seen in the portrayal of the daily struggles of a multitude of poor urban dwellers in a way that challenges the normalized banality of their condition of marginality as a form of social criticism. The formal experimentation appears throughout the text in the constant use of incomplete phrases, unanswered questions, partial lists, unconventional punctuation, and unusual layout. Arguably, the most immediate question that emerges in Eles eram muitos cavalos contends that there is a set of reasons for the occurrence of this form of representation in the particular context of late twentieth-century Brazil. To ask these questions is to think of how Eles eram muitos cavalos favors modes of representation that resonate with ways of experiencing the world in a context of contemporary developments of globalization. As a critical space used to make sense of discourses and experiences of globalization, Eles eram muitos cavalos, I argue, presents new perspectives on the problems and possibilities prompted by globalization. Ruffato's work helps us reflect on the intersections between globalization and fiction and explore its effects by showing that literatures of globalization are not only narratives that partake in constructing fictions of a globalized era but also help expose the fictions that globalization creates. Globalization, as Milton Santos indicates, should be understood in a triple sense (18). First, as a fable, it is presented to us as a fantastic story of a network of an economic-productive-technological future; second, as perversity, where it has intensified a worldwide situation of unequal concentration of wealth; and third, as a possibility of emergence of alternative ways of interacting with the world. Santos's argument acknowledges that deeply embedded in different political, social, and economic realities, globalization cannot be defined as a homogeneous experience, but should be understood as a complex process with inherently different variables and consequences. The global city concept is derivative of that larger framework and speaks to the notion of globalization as fable. In her seminal work on the topic, Saskia Sassen defines global cities as strategic sites where global processes materialize (5). These cities, according to Sassen, are the spaces where crucial political decisions are made and serve as the organizing centers of global power in the geography of globalization. Initially conceptualized as a scholarly tool used to address the effects of globalization in the urban landscape, the concept of a global city turned into a homogenizing organizing principle with enough weight to influence how cities in a globalized world should be structured as well as imagined. …

10.5937/kultura1443168t = The norm, women writers and the truth

In this paper the author classifies and explains some of numerous examples of marginalisation of significant Serbian female authors from the second half of the 19th century and the beginning of the 20th century - Milica Stojadinović Srpkinja, Draga Gavrilović, Mileva Simić, Danica Bandić, Milka Grgurova, Jelena J. Dimitrijević. Their works were negatively evaluated by the dominant intepreters, academic professors and the historians of Serbian literature. Contrary to expectations their criticism was not supported by reasoning. Historians also ignored relevant historical events. To to acknowledge a few female authors meant to present them inadequately, mainly as beautiful women or spinsters. Some other discriminatory facts in presenting female writers were connected with the length of analyses, attitude and the language. The dominant interpreters usually named incomplete list of women authors' works, regularly omitting their translated pieces. There was even an open statement that the author's gender was a starting point for attributing discriminatory values to male or female authors, in favor of the male ones. As one of the most manipulative strategies, one can point out the obstructions to research and publishing of women authors.

An Introduction to Geoffrey Chaucer by Tison Pugh (review)

Reviewed by: An Introduction to Geoffrey Chaucer by Tison Pugh T. S. Miller Tison Pugh, An Introduction to Geoffrey Chaucer (Gainesville: University Press of Florida 2013) xviii + 251 pp. Tison Pugh’s An Introduction to Geoffrey Chaucer enters a market already glutted with introductions and companions to Chaucer. Our options include Derek Brewer’s An Introduction to Chaucer (1984, revised as A New Introduction to Chaucer in 1998); Dieter Mehl’s Geoffrey Chaucer, An Introduction to His Narrative Poetry (1986); The Cambridge Companion to Chaucer (1986, rev. 2003); The Oxford Companion to Chaucer (2003); Chaucer: An Oxford Guide (2005); The Yale Companion to Chaucer (2006); Blackwell’s A Companion to Chaucer (2000); Blackwell’s Chaucer and the Canterbury Tales: A Short Introduction (2003); Blackwell’s Concise Companion to Chaucer (2006); Broadview’s A Companion to Chaucer and His Contemporaries (2009); and finally various introductory anthologies like Beryl Rowland’s original Companion to Chaucer Studies (1968, 1979) or Harold Bloom’s Geoffrey Chaucer (1985), including those volumes that introduce particular works, for example Peter G. Beidler’s entry in the Case Studies in Contemporary Criticism series for The Wife of Bath (1996). As this expansive but incomplete list attests, the idea of an introduction to Chaucer is an old one, yet these companions truly began to proliferate in the twenty-first century: in spite of their abundance, these introductory texts still seem to be a safe bet for publishers, such that Blackwell could produce three separate volumes in a span of only seven years. Is Pugh’s new book a worthwhile endeavor in the face of this plethora of prolegomena? Whether or not we believe that Chaucer studies needed yet another introductory text, I can say with confidence that Pugh has managed to carve out a small niche for his own book by devoting most of it to plot summaries coupled with running commentary, with a target audience of undergraduates having had little or no exposure to Chaucer or medieval literature. In addition to these lengthy plot synopses, the book also includes some excellent modular features, including a concise and highly accessible guide to Middle English pronunciation. Pugh’s Introduction should prove valuable to instructors as a resource for selective use. The first chapter takes the form of a serviceable but greatly abbreviated biographical sketch, only eight pages in length. This obligatory discussion of “Chaucer’s Life and Times” includes all the salacious anecdota from the history of Chaucerian biography, even the poet’s alleged beating of a friar on [End Page 310] Fleetstreet (2). Unfortunately, Pugh cannot spare the time here to emphasize that the story is almost certainly untrue, or explain the narrative’s rhetorical position in the reclamation of Chaucer in Reformation discourse. In my opinion, this section also mishandles Chaucer’s release from the raptus of Cecily Champaigne, although Pugh does describe the incident as “the most vexing episode of Chaucer’s life” (4). Yet “vexing” seems a curious word choice to describe a possible sexual assault committed by an author often adduced as a proto-feminist, and Pugh provides his readers with little direction about how they should interpret this biographical detail. Perhaps Pugh prefers to leave more substantial discussion of the Champaigne case to the individual classroom in part because his Introduction to Geoffrey Chaucer must first present Chaucer as a great author worthy of student attention rather than a potential site of critique. Make no mistake: Pugh’s book is selling Chaucer, consistently advertising the “pleasure” and the “allure” of the author’s poetry, and extolling the poetic genius waiting to be revealed in his “archaic and yet enchanting language” (xii). Readers are even invited to join the ranks of those who “delight in spending time with this man” (xiii), a line that might recall the critiques of the canonization of Chaucer as great author and great man presented in Stephanie Trigg’s 2002 book Congenial Souls. At various later points in An Introduction to Geoffrey Chaucer, Pugh again sacrifices some critical complexity in favor of enticing his audience to appreciate Chaucer, but perhaps this is simply Chaucer’s fate in the undergraduate classroom. Pugh’s goals here remain admirable, especially because the all...

James Wilson versus the Bill of Rights

Americans today may take the Bill of Rights for granted, but its inclusion in the U.S. Constitution originally was controversial. To understand why, I turn to James Wilson, a leading statesman of the founding era and the chief opponent of the Bill of Rights. Among other things, Wilson thought a bill of rights would bind future generations to an incomplete list of rights and deprive them of the right to define individual rights over time. His arguments against a constitutional bill of rights also offer a useful view of the complexity and diversity of American founding era thought.

ODE/IM correspondence for the Fateev model

The Fateev model is somewhat special among two-dimensional quantum field theories. For different values of the parameters,it can be reduced to a variety of integrable systems. An incomplete list of the reductions includes O(3) and O(4) non-linear sigma models and their continuous deformations (2D and 3D sausages, anisotropic principal chiral field), the Bukhvostov-Lipatov model, the N=2 supersymmetric sine-Gordon model, as well as the integrable perturbed SU_2(n)\otimes SU_2(p-2)/SU_2(n+p-2) coset CFT. The model possesses a mysterious symmetry structure of the exceptional quantum superalgebras U_q{\hat{\big(D(2|1;\alpha)}}\big). In this work, we propose the ODE/IM correspondence between the Fateev model and a certain generalization of the classical problem of constant mean curvature embedding of a thrice-punctured sphere in AdS_3.

Predictors of Completeness of Patients’ Self-reported Personal Medication Lists and Discrepancies With Clinic Medication Lists

Transfer of medication information during transitions in care is crucial to preventing medication errors. Few studies evaluate patients' self-reported personal medication lists. To assess completeness of personal medication lists and identify factors associated with incomplete personal lists and discrepancies between personal and clinic medication lists. We analyzed patients' personal medication lists at an academic hospital preoperative clinic from January 2010 to October 2010. Completeness of personal medication lists was measured as reporting the name, dose, and frequency for all prescription and nonprescription medications or dietary supplements. Discrepancies between personal and clinic medication lists were measured as omitted medications or differing directions. Among 94 patients meeting inclusion criteria, 82 (87%) personal medication lists were evaluated. Most personal lists were incomplete (56%; 46/82), missing information for at least one medication reported; 94% (77/82) of personal lists had at least one discrepancy with clinic medication lists (median 4 discrepancies per patient list). On multivariate analyses, taking 10 or more medications (adjusted odds ratio [OR] = 3.52; 95% CI = 1.37 to 9.08) and being divorced, widowed, or single (adjusted OR = 3.10; 95% CI = 1.05 to 9.12) were independent predictors of incomplete personal medication lists. Taking 10 or more medications (adjusted OR = 3.44; 95% CI = 1.35 to 8.78) was also associated with higher rates of medication discrepancies. Patients' self-reported personal medication lists are often incomplete and have discrepancies with clinic medication lists. Interventions are needed to improve medication information transfer between patients, providers and healthcare systems.

Local Search Approaches in Stable Matching Problems

The stable marriage (SM) problem has a wide variety of practical applications, ranging from matching resident doctors to hospitals, to matching students to schools or, more generally, to any two-sided market. In the classical formulation, n men and n women express their preferences (via a strict total order) over the members of the other sex. Solving an SM problem means finding a stable marriage where stability is an envy-free notion: no man and woman who are not married to each other would both prefer each other to their partners or to being single. We consider both the classical stable marriage problem and one of its useful variations (denoted SMTI (Stable Marriage with Ties and Incomplete lists)) where the men and women express their preferences in the form of an incomplete preference list with ties over a subset of the members of the other sex. Matchings are permitted only with people who appear in these preference lists, and we try to find a stable matching that marries as many people as possible. Whilst the SM problem is polynomial to solve, the SMTI problem is NP-hard. We propose to tackle both problems via a local search approach, which exploits properties of the problems to reduce the size of the neighborhood and to make local moves efficiently. We empirically evaluate our algorithm for SM problems by measuring its runtime behavior and its ability to sample the lattice of all possible stable marriages. We evaluate our algorithm for SMTI problems in terms of both its runtime behavior and its ability to find a maximum cardinality stable marriage. Experimental results suggest that for SM problems, the number of steps of our algorithm grows only as O(n log(n)), and that it samples very well the set of all stable marriages. It is thus a fair and efficient approach to generate stable marriages. Furthermore, our approach for SMTI problems is able to solve large problems, quickly returning stable matchings of large and often optimal size, despite the NP-hardness of this problem.

Transition to Adulthood in Cerebral Palsy: Does Independent Walking Make a Difference?

To review current knowledge and identify health status and mobility in individuals with cerebral palsy (CP) as they mature. Specifically, we will describe the relationship between ambulation and health status, particularly the incidence of secondary conditions attributed to premature aging often reported in this population. CorrectionArchives of Physical Medicine and RehabilitationVol. 95Issue 2PreviewPoster 165 in the 2013 ACRM | American Congress of Rehabilitation Medicine Annual Conference abstracts published in October contained an incomplete list of authors. (To view the full issue, please visit the Archives journal website at http://www.archives-pmr.org/issues .) The poster title and corrected author list appear below. Full-Text PDF

When do stable roommate matchings exist? A review

We compare different preference restrictions that ensure the existence of a stable roommate matching. Some of these restrictions are generalized to allow for indifferences as well as incomplete preference lists, in the sense that an agent may prefer remaining single to matching with some agents. We also introduce a new type of cycles and in greater detail investigate the domain of preferences that have no such cycles. In particular, we show how the absence of these cycles relates to the “symmetric utilities hypothesis” by Rodrigues-Neto (J Econ Theory 135:545–550, 2007) when applied to roommate problems with weak preferences.

Chemical Name Extraction Based on Automatic Training Data Generation and Rich Feature Set

The automation of extracting chemical names from text has significant value to biomedical and life science research. A major barrier in this task is the difficulty of getting a sizable and good quality data to train a reliable entity extraction model. Another difficulty is the selection of informative features of chemical names, since comprehensive domain knowledge on chemistry nomenclature is required. Leveraging random text generation techniques, we explore the idea of automatically creating training sets for the task of chemical name extraction. Assuming the availability of an incomplete list of chemical names, called a dictionary, we are able to generate well-controlled, random, yet realistic chemical-like training documents. We statistically analyze the construction of chemical names based on the incomplete dictionary, and propose a series of new features, without relying on any domain knowledge. Compared to state-of-the-art models learned from manually labeled data and domain knowledge, our solution shows better or comparable results in annotating real-world data with less human effort. Moreover, we report an interesting observation about the language for chemical names. That is, both the structural and semantic components of chemical names follow a Zipfian distribution, which resembles many natural languages.

Linear Time Local Approximation Algorithm for Maximum Stable Marriage

We consider a two-sided market under incomplete preference lists with ties, where the goal is to find a maximum size stable matching. The problem is APX-hard, and a 3/2-approximation was given by McDermid [1]. This algorithm has a non-linear running time, and, more importantly needs global knowledge of all preference lists. We present a very natural, economically reasonable, local, linear time algorithm with the same ratio, using some ideas of Paluch [2]. In this algorithm every person make decisions using only their own list, and some information asked from members of these lists (as in the case of the famous algorithm of Gale and Shapley). Some consequences to the Hospitals/Residents problem are also discussed.

Valores de funciones de distribución de probabilidad en el teléfono móvil

La Ingeniería, en su ámbito académico y de aplicación, así como cualquier trabajo formal de investigación precisa del uso de la Estadística, y todo tratamiento estadístico inferencial requiere de la utilización de valores de funciones de distribución de probabilidad que, usualmente, se encuentran disponibles en tablas. En general, el manejo de estas tablas presenta problemas físicos (transporte y consulta dispendiosa) y operativos (listados incompletos y precisión limitada). La investigación titulada “Valores de funciones de distribución de probabilidad en el teléfono móvil”, permitió determinar, mediante un sondeo de necesidad aplicado a estudiantes involucrados con el estudio de la Estadística en la Universidad de Nariño, que los valores más conocidos y utilizados corresponden a las distribuciones Ji-Cuadrado, binomial, t-Student y normal estándar. De igual manera, evidenció el interés de los usuarios en disponer de los valores en cuestión en un medio alternativo que subsanara, al menos en parte, los problemas presentados por “las famosas tablas”. Para tratar de contribuir a la solución, se construyó un software que permite obtener en forma inmediata y dinámica los valores de las funciones de distribución de probabilidad de uso más frecuente a través del teléfono móvil.

Rank Aggregation via Low-Rank and Structured-Sparse Decomposition

Rank aggregation, which combines multiple individual rank lists toobtain a better one, is a fundamental technique in various applications such as meta-search and recommendation systems. Most existing rank aggregation methods blindly combine multiple rank lists with possibly considerable noises, which often degrades their performances. In this paper, we propose a new model for robust rank aggregation (RRA) via matrix learning, which recovers a latent rank list from the possibly incomplete and noisy input rank lists. In our model, we construct a pairwise comparison matrix to encode the order information in each input rank list. Based on our observations, each comparison matrix can be naturally decomposed into a shared low-rank matrix, combined with a deviation error matrix which is the sum of a column-sparse matrix and a row-sparse one. The latent rank list can be easily extracted from the learned low-rank matrix. The optimization formulation of RRA has an element-wise multiplication operator to handle missing values, a symmetric constraint on the noise structure, and a factorization trick to restrict the maximum rank of the low-rank matrix. To solve this challenging optimization problem, we propose a novel procedure based on the Augmented Lagrangian Multiplier scheme. We conduct extensive experiments on meta-search and collaborative filtering benchmark datasets. The results show that the proposed RRA has superior performance gain over several state-of-the-art algorithms for rank aggregation.

State involvement in limiting textbook choice by school districts

Who gets to decide what textbooks are used in America’s public school classrooms varies by state. States can let each school district decide, provide standards that must be followed and make available an incomplete listing of books meeting those standards, or allow schools to choose books only from a list provided by the state. I present a model that provides an explanation for state limits on textbook selection by school districts. I examine the roles played by decision making costs, effectiveness of voters, religious composition, power of teachers, and propensity of state governments to interfere with or to help districts in textbook selection policies at the state level. There has been virtually no research on this topic. My findings corroborate the extant literature that addresses interference by state governments in local affairs and extend the morality politics literature by finding a strong link between religious fundamentalism and state-level policies. I also find that state book lists are less likely (1) in more educated states, where voters are better able to select the most appropriate textbook, (2) in states with smaller school districts, where voters are more involved in the schools, and (3) in states with stronger teacher unions, giving teachers more power in textbook selection.