bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Spike Statistics in Neuronal Systems with Continuous Attractors or Multiple, Discrete Attractor States
Authors: Miller Paul
Published: May 2006

Attractor networks are likely to underlie working memory and integrator circuits in the brain. It is unknown whether continuous quantities are stored in an analog manner or discretized and stored in a set of discrete attractors. In order to investigate the important issue of how to differentiate the two systems, here we compare the neuronal spiking activity that arises from a continuous (line) attractor with that from a series of discrete attractors. Stochastic fluctuations cause the position of the system along its continuous attractor to vary as a random walk, whereas in a discrete attractor, noise causes spontaneous transitions to occur between discrete states at random intervals. We calculate the statistics of spike trains of neurons firing as a Poisson process with rates that vary according to the underlying attractor network. Since individual neurons fire spikes probabilistically and since the state of the network as a whole drifts randomly, the spike trains of individual neurons follow a doubly stochastic (Poisson) point process.

We compare the series of spike trains from the two systems using the autocorrelation function, Fano factor, and interspike interval (ISI) distribution. Although the variation in rate can be dramatically different, especially for short time intervals, surprisingly both the autocorrelation functions and Fano factors are identical, given appropriate scaling of the noise terms. Since the range of firing rates is limited in neurons, we also investigate systems for which the variation in rate is bounded by either rigid limits or because of leak to a single attractor state, such as the Ornstein-Uhlenbeck process. In these cases, the time dependence of the variance in rate can be different between discrete and continuous systems, so that in principle, these processes can be distinguished using second-order spike statistics.
When Response Variability Increases Neural Network Robustness to Synaptic Noise
Authors: Basalyga Gleb , Salinas Emilio
Published: May 2006

Cortical sensory neurons are known to be highly variable, in the sense that responses evoked by identical stimuli often change dramatically from trial to trial. The origin of this variability is uncertain, but it is usually interpreted as detrimental noise that reduces the computational accuracy of neural circuits. Here we investigate the possibility that such response variability might in fact be beneficial, because it may partially compensate for a decrease in accuracy due to stochastic changes in the synaptic strengths of a network. We study the interplay between two kinds of noise, response (or neuronal) noise and synaptic noise, by analyzing their joint influence on the accuracy of neural networks trained to perform various tasks. We find an interesting, generic interaction: when fluctuations in the synaptic connections are proportional to their strengths (multiplicative noise), a certain amount of response noise in the input neurons can significantly improve network performance, compared to the same network without response noise. Performance is enhanced because response noise and multiplicative synaptic noise are in some ways equivalent. So if the algorithm used to find the optimal synaptic weights can take into account the variability of the model neurons, it can also take into account the variability of the synapses. Thus, the connection patterns generated with response noise are typically more resistant to synaptic degradation than those obtained without response noise. As a consequence of this interplay, if multiplicative synaptic noise is present, it is better to have response noise in the network than not to have it. These results are demonstrated analytically for the most basic network consisting of two input neurons and one output neuron performing a simple classification task, but computer simulations show that the phenomenon persists in a wide range of architectures, including recurrent (attractor) networks and sensorimotor networks that perform coordinate transformations. The results suggest that response variability could play an important dynamic role in networks that continuously learn.
Optimal Neuronal Tuning for Finite Stimulus Spaces
Authors: Brown W. Michael , Bäcker Alex
Published: May 2006

The efficiency of neuronal encoding in sensory and motor systems has been proposed as a first principle governing response properties within the central nervous system. We present a continuation of a theoretical study presented by Zhang and Sejnowski, where the influence of neuronal tuning properties on encoding accuracy is analyzed using information theory. When a finite stimulus space is considered, we show that the encoding accuracy improves with narrow tuning for one- and two-dimensional stimuli. For three dimensions and higher, there is an optimal tuning width.
Temporal Decoding by Phase-Locked Loops: Unique Features of Circuit-Level Implementations and Their Significance for Vibrissal Information Processing
Authors: Zacksenhouse Miriam , Ahissar Ehud
Published: May 2006

Rhythmic active touch, such as whisking, evokes a periodic reference spike train along which the timing of a novel stimulus, induced, for example, when thewhiskers hit an external object, can be interpreted. Previous work supports the hypothesis that the whisking-induced spike train entrains a neural implementation of a phase-locked loop (NPLL) in the vibrissal system. Hereweextend thiswork and explorehowthe entrained NPLL decodes the delay of the novel, contact-induced stimulus and facilitates object localization. We consider two implementations of NPLLs, which are based on a single neuron or a neural circuit, respectively, and evaluate the resulting temporal decoding capabilities. Depending on the structure of the NPLL, it can lock in either a phase- or co-phase-sensitive mode, which is sensitive to the timing of the input with respect to the beginning of either the current or the next cycle, respectively. The co-phase-sensitive mode is shown to be unique to circuit-based NPLLs. Concentrating on temporal decoding in the vibrissal system of rats, we conclude that both the nature of the information processing task and the response characteristics suggest that the computation is sensitive to the co-phase. Consequently, we suggest that the underlying thalamocortical loop should implement a circuit-based NPLL.
Representation and Timing in Theories of the Dopamine System
Authors: Daw Nathaniel D. , Courville Aaron C. , Touretzky David S.
Published: May 2006

Although the responses of dopamine neurons in the primate midbrain are well characterized as carrying a temporal difference (TD) error signal for reward prediction, existing theories do not offer a credible account of how the brain keeps track of past sensory events that may be relevant to predicting future reward. Empirically, these shortcomings of previous theories are particularly evident in their account of experiments in which animals were exposed to variation in the timing of events. The original theories mispredicted the results of such experiments due to their use of a representational device called a tapped delay line.

Here we propose that a richer understanding of history representation and a better account of these experiments can be given by considering TD algorithms for a formal setting that incorporates two features not originally considered in theories of the dopaminergic response: partial observability (a distinction between the animal's sensory experience and the true underlying state of the world) and semi-Markov dynamics (an explicit account of variation in the intervals between events). The new theory situates the dopaminergic system in a richer functional and anatomical context, since it assumes (in accord with recent computational theories of cortex) that problems of partial observability and stimulus history are solved in sensory cortex using statistical modeling and inference and that the TD system predicts reward using the results of this inference rather than raw sensory data. It also accounts for a range of experimental data, including the experiments involving programmed temporal variability and other previously unmodeled dopaminergic response phenomena, which we suggest are related to subjective noise in animals' interval timing. Finally, it offers new experimental predictions and a rich theoretical framework for designing future experiments.
Experiments with AdaBoost.RT, an Improved Boosting Scheme for Regression
Authors: Shrestha D. L. , Solomatine D. P.
Published: May 2006

The application of boosting technique to regression problems has received relatively little attention in contrast to research aimed at classification problems. This letter describes a new boosting algorithm, AdaBoost.RT, for regression problems. Its idea is in filtering out the examples with the relative estimation error that is higher than the preset threshold value, and then following the AdaBoost procedure. Thus, it requires selecting the suboptimal value of the error threshold to demarcate examples as poorly or well predicted. Some experimental results using the M5 model tree as a weak learning machine for several benchmark data sets are reported. The results are compared to other boosting methods, bagging, artificial neural networks, and a single M5 model tree. The preliminary empirical comparisons show higher performance of AdaBoost.RT for most of the considered data sets.
A Connectionist Computational Model for Epistemic and Temporal Reasoning
Authors: Garcez Artur S. d'Avila , Lamb Luís C.
Published: May 2006

The importance of the efforts to bridge the gap between the connectionist and symbolic paradigms of artificial intelligence has been widely recognized. The merging of theory (background knowledge) and data learning (learning from examples) into neural-symbolic systems has indicated that such a learning system is more effective than purely symbolic or purely connectionist systems. Until recently, however, neural-symbolic systems were not able to fully represent, reason, and learn expressive languages other than classical propositional and fragments of first-order logic. In this article, we show that nonclassical logics, in particular propositional temporal logic and combinations of temporal and epistemic (modal) reasoning, can be effectively computed by artificial neural networks. We present the language of a connectionist temporal logic of knowledge (CTLK). We then present a temporal algorithm that translates CTLK theories into ensembles of neural networks and prove that the translation is correct. Finally, we apply CTLK to the muddy children puzzle, which has been widely used as a testbed for distributed knowledge representation. We provide a complete solution to the puzzle with the use of simple neural networks, capable of reasoning about knowledge evolution in time and of knowledge acquisition through learning.
The Hand Is More Easily Fooled than the Eye: Users Are More Sensitive to Visual Interpenetration than to Visual-Proprioceptive Discrepancy
Authors: Burns Eric , Razzaque Sharif , Panter Abigail T. , Whitton Mary C. , McCallus Matthew R. , Brooks Frederick P.
Published: May 2006

A virtual environment (VE) user's avatar may penetrate virtual objects. Some VE designers prevent visual interpenetration, assuming that prevention improves user experience. However, preventing visual avatar interpenetration causes a discrepancy between visual and proprioceptive cues. We investigated users' detection thresh-olds for visual interpenetration and visual-proprioceptive discrepancy and found that users are much less sensitive to visual-proprioceptive discrepancy than to visual interpenetration. We propose using this result to better deal with user penetration of virtual objects.
The Hedgehog: A Novel Optical Tracking Method for Spatially Immersive Displays
Authors: Vorozcovs A. , Stuerzlinger W. , Hogue A. , Allison R. S.
Published: May 2006

Existing commercial technologies do not adequately meet the requirements for tracking in fully enclosed Virtual Reality displays. We present a novel six degree of freedom tracking system, the Hedgehog; which overcomes several limitations inherent in existing sensors and tracking technology. The system reliably estimates the pose of the user's head with high resolution and low spatial distortion. Light emitted from an arrangement of lasers projects onto the display walls. An arrangement of cameras images the walls and the two-dimensional centroids of the projections are tracked to estimate the pose of the device. The system is able to handle ambiguous laser projection configurations, static and dynamic occlusions of the lasers, and incorporates an auto-calibration mechanism due to the use of the SCAAT (single constraint at a time) algorithm. A prototype system was evaluated relative to a state-of-the-art motion tracker and showed comparable positional accuracy (1–2 mm RMS) and significantly better absolute angular accuracy (0.1° RMS).
A Spring Model for Whole-Hand Virtual Grasping
Authors: Borst Christoph W. , Indugula Arun P.
Published: May 2006

We present a physically-based approach to grasping and manipulation of virtual objects that produces visually realistic results, addresses the problem of visual inter-penetration of hand and object models, and performs force rendering for force-feedback gloves, in a single framework. Our approach couples a simulation-controlled articulated hand model to tracked hand configuration using a system of linear and torsional virtual spring-dampers. We discuss an implementation of our approach that uses a widely available simulation tool for collision detection and response. We pictorially illustrate the resulting behavior of the virtual hand model and of grasped objects, discuss user behavior and difficulties encountered, and show that the simulation rate is sufficient for control of current force-feedback glove designs. We also present a prototype system for natural whole-hand interactions in a desktop-sized workspace.
Enabling Scalability by Partitioning Virtual Environments Using Frontier Sets
Authors: Steed Anthony , Angus Cameron
Published: May 2006

We present a class of partitioning scheme that we have called frontier sets. Frontier sets build on the notion of a potentially visible set (PVS). In a PVS, a world is subdivided into cells and for each cell all the other cells that can be seen are computed. In contrast, a frontier set considers pairs of cells, A and B. For each pair, it lists two sets of cells (two frontiers), FAB and FBA. By definition, from no cell in FAB is any cell in FBA visible and vice versa.

Our initial use of frontier sets has been to enable scalability in distributed networking. This is possible because, for example, if at time t0 Player1 is in cell A and Player2 is in cell B, as long as they stay in their respective frontiers, they do not need to send update information to each other.

In this paper we describe two strategies for building frontier sets. Both strategies are dynamic and compute frontiers only as necessary at runtime. The first is distance-based frontiers. This strategy requires precomputation of an enhanced potentially visible set. The second is greedy frontiers. This strategy is more expensive to compute at runtime, however it leads to larger and thus more efficient frontiers.

Network simulations using code based on the Quake II engine show that frontiers have significant promise and may allow a new class of scalable peer-to-peer game infrastructures to emerge.
Measuring Gaze Direction Perception Capability of Humans to Design Human Centered Communication Systems
Authors: Imai Tomoko , Sekiguchi Dairoku , Inami Masahiko , Kawakami Naoki , Tachi Susumu
Published: May 2006

We describe experiments designed to measure gaze direction perception capability of humans under face-to-face and display mediated conditions. Gaze perception capability was determined by means of the absolute values of the pitch differences between a looker's actual regards and participants' judgments. We compared the capability under face-to-face, stereoscopic image, and monoscopic image conditions. On average, participants perceived the looker's gaze direction most accurately under the face-to-face condition. As expected, the accuracy under the stereoscopic image condition was higher than the results obtained under the monoscopic image condition. However, individual data did not follow the expected order and our exploratory experiments showed that participants with narrower interpupillary distance than the distance between two stereo cameras had difficulty in judging gaze directions. We also found that the perception of the pitch component of gaze direction is affected by gaze transmission methods but the yaw component is robust and is not affected by the transmission conditions.
Human Behavior Models for Agents in Simulators and Games: Part II: Gamebot Engineering with PMFserv
Authors: Silverman Barry G. , Bharathy Gnana , O'Brien Kevin , Cornwell Jason
Published: May 2006

Many producers and consumers of legacy training simulator and game environments are beginning to envision a new era where psycho-socio-physiologic models could be interoperated to enhance their environments' simulation of human agents. This paper explores whether we could embed our behavior modeling framework (described in the companion paper, Part 1) behind a legacy first person shooter 3D game environment to recreate portions of the Black Hawk Down scenario. Section 1 amplifies the interoperability needs and challenges confronting the field, presents the questions that are examined, and describes the test scenario. Sections 2 and 3 review the software and knowledge engineering methodology, respectively, needed to create the system and populate it with bots. Results (Section 4) and discussion (Section 5) reveal that we were able to generate plausible and adaptive recreations of Somalian crowds, militia, women acting as shields, suicide bombers, and more. Also, there are specific lessons learned about ways to advance the field so that such interoperabilities will become more affordable and widespread.
On Consistency and Network Latency in Distributed Interactive Applications: A Survey—Part I
Authors: Delaney Declan , Ward Tomás , McLoone Seamus
Published: May 2006

This paper is the first part of a two-part paper that documents a detailed survey of the research carried out on consistency and latency in distributed interactive applications (DIAs) in recent decades. Part I reviews the terminology associated with DIAs and offers definitions for consistency and latency. Related issues such as jitter and fidelity are also discussed. Furthermore, the various consistency maintenance mechanisms that researchers have used to improve consistency and reduce latency effects are considered. These mechanisms are grouped into one of three categories, namely time management, information management, and system architectural management. This paper presents the techniques associated with the time management category. Examples of such mechanisms include time warp, lock step synchronization, and predictive time management. The remaining two categories are presented in part II of the survey.
The Borderline of Science: On the Value of Factor Analysis for Understanding Presence
Authors: Waller David , Bachmann Eric R.
Published: May 2006

The use of exploratory factor analysis in research on presence is summarized and critically examined. We conclude that, as with research on human intelligence in the first half of the twentieth century, exploratory factor analysis has been extremely limited in its ability to test hypotheses and to advance theory. To illustrate these ideas, we examine a recent analysis by Witmer, Jerome, and Singer (2005, Presence 14, 298–312). We suggest that analyses based on confirmatory methods are in general better suited to advance our understanding of the concept of presence.
Anger Feelings and Anger Expression as a Mediator of the Effects of Witnessing Family Violence on Anxiety and Depression in Japanese Adolescents
Authors: Kitamura Toshinori , Hasui Chieko
Published: May 2006

The effects of anger feelings (rated by the State-Trait Anger Expression Inventory) and witnessing family violence on anxiety and depression (rated by the Hospital Anxiety and Depression Scale) were examined in 457 junior high school students. Anxiety and depression scores were correlated with frequencies of witnessing family violence. In a regression analysis, however, after controlling for the demographic variables and depression score, the anxiety score was predicted by State Anger, Anger-Out, and Anger-Control; the depression score was predicted, after controlling for the demographic and anxiety score, by State Anger, Anger-In positively, and by Anger-Out and Anger-Control negatively. Witnessing family violence failed to add significant contribution in predicting anxiety or depression. These results were generally supported by structural equation modeling. The effects of witnessing family violence on dysphoric mood may be mediated by anger feelings. The style of dysphoric mood may be predicted by the style of anger expression.
Violence-Related Attitudes and Beliefs
Authors: Brand Pamela A. , Anastasio Phyllis A.
Published: May 2006

The 50-item Violence-Related Attitudes and Beliefs Scale (V-RABS) includes three subscales measuring possible causes of violent behavior (environmental influences, biological influences, and mental illness) and four subscales assessing possible controls of violent behavior (death penalty, punishment, prevention, and catharsis). Each subscale demonstrates good internal consistency and test-retest reliability. Thus, the V-RABS and its component subscales can be valuable research tools for understanding people's beliefs about the causes and controls of violent crime.
The Dark Figure of Infanticide in England and Wales
Authors: Brookman Fiona , Nolan Jane
Published: May 2006

Infants aged younger than 12 months have the highest homicide victimization rate of any single age group in England and Wales. In addition, there are good grounds for believing that the official homicide statistics for this particular age group are an underestimate and subject to distortion. At the same time there is evidence mounting in the United Kingdom that some parents have been incorrectly convicted of infanticide. This article first explores all recorded cases of infanticide in England and Wales for the period 1995-2002 (298 cases in total). Characteristics of the offenders, victims, offense, and court outcomes are examined. The second part of the article takes a critical gaze at the complexities involved in distinguishing infanticide from sudden infant death syndrome (SIDS) and other sudden unexplained deaths in infancy (SUDI). The article ends by considering in what ways infant deaths might be more effectively investigated.
Effects of Victims' Characteristics on Attitudes Toward Hate Crimes
Authors: Saucier Donald A. , Brown Tamara L. , Mitchell Raquel C. , Cawman Audrey J.
Published: May 2006

Hate crimes are motivated by perpetrators' prejudice toward targets' group. To examine individuals' attitudes toward hate crime perpetrators and targets, participants responded to vignettes of court cases in which the victim's group membership was varied. Results showed that participants recommended more severe sentences for perpetrators when the targets of their crimes were not White males or White females and reported those crimes as more closely fitting the definition of “hate crime.” These results show that participants consider penalty enhancements appropriate for hate crimes and that they do not consider crimes against women to be hate crimes, consistent with present hate crime legislation. These results have implications for the utility and support of hate crime legislation but may showcase the resistance to expanding the legislation to protect individuals of other groups, especially women.
Exploring the Possible Link Between Childhood and Adolescent Bestiality and Interpersonal Violence
Authors: Hensley Christopher , Tallichet Suzanne E. , Singer Stephen D.
Published: May 2006

Bestiality is a serious although less frequently occurring form of animal cruelty that may be linked to subsequent aggression against humans. This investigation examines whether a perpetrator's race, childhood residence, education, commission of a personal crime, and the number of personal crimes committed affects acts of bestiality committed during childhood or adolescence among a sample of incarcerated males. The results show that respondents with less education and those who had been convicted of committing crimes against people on one or more occasions were more likely to have had sex with animals during their childhood or adolescence than other respondents in the sample. These findings lend some support to the sexually polymorphous theory that among these perpetrators sex and aggression have become mutually inclusive and that bestiality as a form of animal cruelty may be linked with interpersonal human violence.
Exposure to Interpersonal Violence as a Predictor of PTSD Symptomatology in Domestic Violence Survivors
Authors: Griffing Sascha , Lewis Carla S. , Chu Melissa , Sage Robert E. , Madry Lorraine , Primm Beny J.
Published: May 2006

This study examines the interrelationships between childhood abuse, exposure to maternal domestic violence, and posttraumatic stress disorder (PTSD) symptomatology in a multiethnic sample of 111 adult female residents of a domestic violence (DV) shelter. Participants completed structured interviews about the DV and their prior violence exposure, as well as the Impact of Event Scale–Revised. As hypothesized, there was high co-occurrence between exposure to maternal DV and childhood physical and sexual abuse, and the frequency of lifetime violence exposure predicted PTSD symptomatology. A series of multiple regressions indicated a more complex pattern of relationships, in which specific forms of prior violence exposure predicted different PTSD symptom dimensions. A history of witnessing maternal DV predicted intrusion symptoms, and a history of childhood sexual abuse predicted hyperarousal symptoms. Ethnicity was not related to levels of violence exposure or to PTSD symptoms. Clinical implications of the findings are discussed.
Alcohol Problems and the Differentiation of Partner, Stranger, and General Violence
Authors: Cogan Rosemary , Ballinger Bud C.
Published: May 2006

To explore the relationship between alcohol problems and physical violence with partners and strangers, 457 college men and 958 college women with low, intermediate, or high scores on the Short Michigan Alcohol Screening Test reported conflict tactics on the Conflict Tactics Scale in the past year to and by partners and strangers. More men than women had high alcohol problems scores. Men with alcohol problems were more likely than other men to commit violence toward strangers or to partners and strangers. However, men with alcohol problems were not more likely than other men to commit violence toward partners only. Among women, alcohol problems had little relationship to committing violence or being the victim of violence.
Intimate Partner Violence, PTSD, and Adverse Health Outcomes
Authors: Dutton Mary Ann , Green Bonnie L. , Kaltman Stacey I. , Roesch Darren M. , Zeffiro Thomas A. , Krause Elizabeth D.
Published: May 2006

The high prevalence of adverse health outcomes related to intimate partner violence (IPV) is well documented. Yet we know little about the pathways that lead to adverse health outcomes. Research concerning the psychological, biological, neurological, behavioral, and physiological alterations following exposure to IPV—many of which are associated with posttraumatic stress disorder (PTSD)—represents a promising area of empirical discovery. New technologies and interdisciplinary collaborative efforts are required to integrate diverse methodologies and to apply new findings to improving the health and well being of those affected by IPV. This article focuses on victimization by IPV and addresses the most important research findings in the last 20 years (health and mental health burden of IPV), the most important research issue for the next decade (pathways between IPV and adverse health outcomes), and the most promising methodological innovation for the study of IPV (integrated, interdisciplinary, biobehavioral methodology).
Do Social Workers Make Better Child Welfare Workers Than Non–Social Workers?
Authors: Perry Robin E.
Published: May 2006

Objective: To empirically examine whether the educational background of child welfare workers in Florida impacts on performance evaluations of their work. Method: A proportionate, stratified random sample of supervisor and peer evaluations of child protective investigators and child protective service workers is conducted. ANOVA procedures are used to test if performance scores on a multitude of items differ for workers with university degrees in social work, psychology, sociology, criminology, education, business, and other fields. Results: The ratings of social workers' skills and competency do not statistically differ from those workers with other educational backgrounds on 20 measures of performance. Conclusion: Findings suggest that the educational background of child welfare workers is a poor predictive variable of their performance as evaluated by supervisors and peers. However, more research is needed to determine if performance evaluations of workers are positively correlated with successful service outcomes with clients.
Why Don't Social Workers Make Better Child Welfare Workers Than Non–Social Workers?
Authors: Holosko Michael J.
Published: May 2006

This invited response contends that Dr. Perry's main findings are really not that surprising nor should they be. It argues that he should have asked a different question rather than the one posed in his title. The reasons offered for social workers not differing from non–social workers in their respective performance of tasks at Florida's Department of Children and Families are the relative sameness in baccalaureate education at their foundation years, personality characteristics of those who enter helping professions in general, and the pervasive organizational culture in which they work. The response argues for an understanding of the sameness rather than an apology for the nondifference.
Social Workers in Child Welfare: Ready for Duty
Authors: Whitaker Tracy , Clark Elizabeth J.
Published: May 2006

This article responds to Do Social Workers Make Better Child Welfare Workers than Non-Social Workers? by Dr. Robin E. Perry. The article articulates National Association of Social Workers'support for a professional social work labor force to serve children and their families and for continued federal investment in the training of these workers. Professionally educated and trained social workers in child welfare agencies have good retention rates, report high satisfaction with their work, and have a solid understanding of the child welfare service arena. Children and families in crisis deserve access to the best resources available, including professional social workers.
No Simple Answers to a Complex Question: A Response to Perry
Authors: Zlotnik Joan Levy
Published: May 2006

The issue of whether professional social workers make better child welfare workers than nonsocial workers is a considerably complex one. Simply determining better is itself a difficult undertaking. For example, does better mean reduced turnover among professionally trained social worker child welfare specialists, or should it mean better outcomes for children served? Considerable prior work supports the contention that social workers can make better child welfare workers than non–social workers, research conducted using diverse methodologies and among different states. The performance evaluation process used by Perry may not be a valid method of assessing child welfare worker skills. However, his results certainly indicate the need for additional and more rigorous empirical research to answer the question he posed.
The Context and Process for Performance Evaluations: Necessary Preconditions for the Use of Performance Evaluations as a Measure of Performance—A Critique of Perry
Authors: Mccarthy Mary L.
Published: May 2006

This article challenges Perry's research using performance evaluations to determine whether the educational background of child welfare workers is predictive of performance. Institutional theory, an understanding of street-level bureaucracies, and evaluations of field education performance measures are offered as necessary frameworks for Perry's findings. Performance evaluations are insufficient absent a discussion of the link between organizational goals, supervisor training, practice protocols, and performance measurement tools. Three questions inform this critique and examples from child welfare practice illustrate the ways performance measures in this study may actually be a measure of organizational stasis and pressure to conform to practice as it has been.
The (Mis)Measurement of Job Performance in Child Welfare Using (Non)Experimental Design
Authors: Lieberman Alice A. , Levy Michelle M.
Published: May 2006

This commentary explicates two principal arguments against the conclusions drawn by Robin Perry in his article “Do Social Workers Make Better Child Welfare Workers Than Non-Social Workers?” The first concerns the methodology used, whereas the second centers on the measurement of the dependent variable, performance expectation. Considering the difficulty of drawing any valid conclusions given these flaws, the authors suggest that the reader view this study with extreme caution. Suggestions for subsequent research efforts in this area are offered.
Broad Study but Narrow Question: A Friendly Critique of Perry's Article
Authors: Ellett Alberta J.
Published: May 2006

This article is a critique of the article by Robin Perry in this issue that describes a study in Florida to compare supervisor and peer performance evaluations of child welfare staff. An overview of prior studies related to the importance of the social work degree is provided. Subsequently, selected technical, design issues, and results in the Perry study are identified and discussed. Issues and speculations about the validity of supervisor and peer ratings in Perry's study and other studies are addressed. Finally, a discussion of the need to broaden perspectives on the importance of the social work degree is included. Perry's results indicate more about the invalidity of supervisor and peer ratings of child welfare staff performance than anything about the importance of the social work degree for effective job performance. Perry's study focused on a narrow issue pertaining to a larger set of issues.
We Really Should Get on With It: An Argument for Not Assuming Social Workers Make Better Child Welfare Workers Than Non–Social Workers
Authors: Mathias Chris
Published: May 2006

Being in full support of asking the question, “Do social workers make better child welfare workers?” we must be open to what we might find. It may bring us closer to what practices work and what practices do not work for children and families. By framing the issue in this way, we remove the debate about social worker usefulness in child welfare and move toward advancing the field of child welfare. Perhaps child welfare is child welfare and not social work; perhaps social workers do child welfare better than those with different educational backgrounds. We do not now. Grappling with this question should push all social workers (administrators, researchers, clinicians, practitioners, community organizers, and case managers) to advocate for necessary system change so that more focused studies can be done to improve practice to better help the children and families.
ACORN's Accelerated Income Redistribution Project: A Program Evaluation
Authors: Brooks Fred , Russell Daniel , Fisher Robert
Published: May 2006

Objective: This study evaluated the Association of Community Organizations for Reform Now's (ACORN) efforts to increase the uptake of families claiming the earned income tax credit through door-to-door canvassing and managing free tax preparation clinics in three pilot cities. Method: The mixed-method program evaluation included administrative record review, a telephone survey (N = 1,063), and individual and focus group interviews. Results: During the 2003 tax year, ACORN prepared taxes at no charge for 3,850 families who collected a total of $4 million in earned income tax credit and other tax credits. In two pilot cities, ACORN led all other free sites in number of returns filed. Canvassing and word of mouth were the most productive marketing tools for the free tax preparation sites. Conclusions: Canvassing appears to be effective outreach in getting families to take advantage of free tax preparation. ACORN's approach to combining services and direct action organizing appears to be a good fit and sustainable.
Assessment of Perceived Parental Psychological Control in Chinese Adolescents in Hong Kong
Authors: Shek Daniel T. L.
Published: May 2006

Objective: There is no validated self-report measure of parental psychological control in the Chinese culture. The reliability and validity of the Chinese Paternal Psychological Control Scale (CPPCS) and Chinese Maternal Psychological Control Scale (CMPCS) were examined. Method: A total of 3,017 Chinese secondary school students responded to the CPPCS and CMPCS and measures of psychological well-being, parent-child relational qualities, parental knowledge, parental monitoring, and perceived parental endorsement of traditional Chinese parenting beliefs. Results: The CPPCS and CMPCS were internally consistent in different samples. Evidence supporting the convergent validity (negative relationships between the CPPCS and CMPCS with psychological well-being, parent-child relational qualities, and parental knowledge but positive relationship with perceived parental endorsement of traditional Chinese parental beliefs) and discriminant validity (weak relationship between psychological control measures and parental monitoring) of these two measures was found. Conclusions: The present study suggests that the CPPCS and CMPCS possess sound psychometric properties that can objectively assess perceived parental psychological control in Chinese adolescents.
B.A.s are B.S. in Child Welfare: Did Anybody Learn Anything?
Authors: Hughes Ronald C. , Baird Christopher
Published: May 2006

Robin E. Perry's study compared the job performance of public child welfare agency caseworkers who had received bachelors degrees in social work and caseworkers whose bachelors degrees were in other practice fields. The study found no significant effects on subsequent job performance from having received a social work degree. Several methodological concerns are identified that challenge this conclusion, including whether the agency performance evaluations, used as the primary means of measuring job performance, provided accurate or complete information regarding the job performance of the study subjects. It is suggested that conclusions not be drawn about the impact of social work education on the job performance of child welfare on the basis of this study.
An Important Question Half-Answered: A Response to Perry's Article
Authors: Dickinson Nancy S.
Published: May 2006

Robin E. Perry's article, Do Social Workers Make Better Child Welfare Workers Than Non-Social Workers?, is an important step in studying the relationship between education of child welfare workers and their job performance. In this case, however, workers’ performance was measured by poorly designed performance evaluation tools completed routinely by Florida supervisors and peers. The iterative and labor-intensive process of job analysis, competency development, and performance appraisal validation is not typically done in child welfare nor studied in social work research. Until we can validate and reliably measure the knowledge and skills necessary to perform child welfare work, we cannot answer many questions about the relationship between worker education and performance on the job.
A Suggested Authors' Checklist for Submitting Manuscripts to Research on Social Work Practice
Authors: Holosko Michael J.
Published: May 2006

A checklist of factors to be considered by authors planning to submit an outcome study for editorial review and possible publication in the journal Research on Social Work Practice is presented. This list is intended to help authors assure themselves that their article is indeed appropriate for this journal. It is hoped that the presentation of this type of checklist will further advance the methodological rigor of research into the outcomes of social work practice and stimulate other research journals in our discipline to adopt similarly clear guidelines.
Competency Is Not Guaranteed by the Letters That Follow Your Name: A Response to My Critics
Authors: Perry Robin E.
Published: May 2006

This article is a formal response to those that authored critiques of the author1's research. Each author has provided a thoughtful and critical perspective highlighting the perceived merits and demerits of the research questions posed, theoretical assumptions underlying the inquiry, study design and methodology, and interpretations garnered from summarized findings. In the end, no sound evidence was presented that refutes suggestions that the educational background of child welfare workers is a poor predictive variable of their performance. Regardless, taken together, the insights and criticisms of my colleagues provide other researchers with a foundation for better answering the questions the authors pose. These include questions about the efficacy of Title IV-E educational programs, what factors are predicative of competent child welfare practice, the means and mechanisms by which practice and worker competency is evaluated, and who has a right or privilege to receive specialized child welfare education and training.
Regionalism and Reform
Authors: Kantor Paul
Published: May 2006

Advocates of regional political cooperation find favor with political theorists while encountering widespread rejection by real-world governments. Why do practitioners often fail to follow the reformers? Employing a comparative perspective, this analysis examines theories of regional reform and then surveys metropolitan political cooperation within a context that theorists expect should be highly supportive of it—Randstad Holland and the Amsterdam metropolitan area. Regional political development finds little success in this region. Dutch experience suggests that regional theory makes unrealistic assumptions about the conditions that favor intergovernmental cooperation and underestimates the political barriers to this kind of reform.
Determinants of Neighborhood Satisfaction in Fee-Based Gated and Nongated Communities
Authors: Chapman David W. , Lombard John R.
Published: May 2006

Neighborhoods unable to adequately satisfy perceived resident needs are susceptible to the migration of their inhabitants to areas that better address their needs. Using the American Housing Survey, the authors examine neighborhood satisfaction and its relationship to perceptions of residents living in both gated and nongated fee-based neighborhoods. The findings indicate that respondent age and the lack of knowledge of crime have the largest positive impact on how the residents rated their neighborhoods. While chronological age may have myriad possible influential factors, the simple knowledge by residents of neighborhood crime has implications for crime prevention and community awareness efforts.
Impact Fees, Growth Management, and Development
Authors: Jeong Moon-Gi , Feiock Richard C.
Published: May 2006

This article explores economic consequences of impact fees on local economic development and job growth. The authors focus on the implied contractual relationship between local governments and the development community in shaping patterns of economic growth in the community. Pooled time series cross-section analyses are employed to estimate economic consequences of impact fees in 66 Florida counties from 1991 to 2001. Contrary to the conventional wisdom that impact fees increase development costs and impede economic development, the authors report that implementation of impact fee systems enhances economic performance and lead to job growth.
Rail Transit Security in an International Context
Authors: Loukaitou-Sideris Anastasia , Taylor Brian D. , Fink Camille N. Y.
Published: May 2006

Open, accessible urban public transportation systems have become increasingly frequent targets for terrorists in recent years. This article draws from a series of interviews with transit officials responsible for the security of rail transit systems, as well as architects and engineers responsible for designing and operating these systems in four world cities: London, Paris, Tokyo, and Madrid. The findings show that transit security is, not surprisingly, a major and growing concern of transit operators in these cities. Collectively, the interviewees report drawing on a broad mix of strategies to respond to terrorism and, in the process, struggle mightily to balance the trade-offs between increased security on one hand and openness and attractiveness of their systems on the other. Accordingly, coordination between transit agencies and police/intelligence agencies has become a crucial component of security planning.
Reclaiming Cultural Heritage in Singapore
Authors: Yuen Belinda
Published: May 2006

The issue of cultural heritage in urban settings is of increasing importance as cities seek a better future in a globalizing world. This article aims to explore how such heritage themes and assets are treated in rapidly urbanizing cities to redress the creation of tabula rasa. Using the case study of Singapore's latest attempt to build a distinctive global city, the article will analyze the changing images of heritage and discuss how heritage conservation may yet give urban redevelopment unique places. The challenge for Singapore, as in other cities, is to identify those parts of the urban environment most worthy of preservation while fostering a new and distinctive skyline.
Higher urine 1-hydroxy pyrene glucuronide (1-OHPG) is associated with tobacco smoke exposure and drinking maté in healthy subjects from Rio Grande do Sul, Brazil
Authors: Fagundes Renato B , Abnet Christian C , Strickland Paul T , Kamangar Farin , Roth Mark J , Taylor Philip R , Dawsey Sanford M
Published: May 2006

Background

The highest rates of esophageal squamous cell carcinoma (ESCC) in Brazil occur in Rio Grande do Sul, the most southern state, which has incidence rates of 20.4/100,000/year for men and 6.5/100,000/year for women. Exposure to carcinogenic polycyclic aromatic hydrocarbons (PAHs) through tobacco smoke and other sources may increase the risk of ESCC. The aims of the current study were to investigate the degree and sources of PAH exposure of the inhabitants of this region of southern Brazil.

Methods

Two hundred healthy adults (half smokers, half non smokers, half male and half female) were recruited, given a standardized questionnaire, and asked to provide a urine sample for measurement of 1-hydroxypyrene glucuronide (1-OHPG), a PAH metabolite). Urine 1-OHPG concentrations were measured using immunoaffinity chromatography and synchronous fluorescence spectroscopy and urine cotinine was measured using a dipstick test. We examined factors associated with 1-OHPG concentration using Wilcoxon tests and multiple linear regression.

Results

Urine 1-hydroxypyrene glucuronide (1-OHPG) was successfully measured on 199 subjects. The median (interquartile range) of urine 1-OHPG in the 199 participants was 2.09 pmol/mL (0.51, 5.84). Tobacco smoke exposure and maté drinking were statistically significantly associated with higher urine 1-OHPG concentrations in the multivariate linear regression model.

Conclusion

Tobacco smoke and maté both contribute to high levels of benzo[a]pyrene exposure in the people of southern Brazil. This high PAH exposure may contribute to the high rates of ESCC observed in this population. The increased urine 1-OHPG concentrations associated with maté suggest that contaminants, not just thermal injury, may help explain the increased risk of ESCC previously reported for maté consumption.