Using Latent Trait Modeling to Conceptualize an Alcohol Problems Continuum.

Recent research points toward the viability of conceptualizing alcohol problems as arrayed along a continuum. Nevertheless, modern statistical techniques designed to scale multiple problems along a continuum (latent trait modeling; LTM) have rarely been applied to alcohol problems. This study applies LTM methods to data on 110 problems reported during in-person interviews of 1,348 middle-aged men (mean age=43) from the general population. The results revealed a continuum of severity linking the 110 problems, ranging from heavy and abusive drinking, through tolerance and withdrawal, to serious complications of alcoholism. These results indicate that alcohol problems can be arrayed along a dimension of severity and emphasize the relevance of LTM to informing the conceptualization and assessment of alcohol problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Identifying Psychopathy Subtypes on the Basis of Personality Structure.

The authors used model-based cluster analysis to identify subtypes of criminal psychopaths on the basis of differences in personality structure. Participants included 96 male prisoners diagnosed as psychopathic, using the Psychopathy Checklist Revised (PCL-R; R. D. Hare, 1991). Personality was assessed using the brief form of the Multidimensional Personality Questionnaire (MPQ-BF; C. J. Patrick, J. J. Curtin, & A. Tellegen, 2002). The best-fitting model yielded two clusters. Emotionally stable psychopaths were characterized by low Stress Reaction and high Agency. Aggressive psychopaths were characterized by high Negative Emotionality, low Constraint, and low Communion. These results suggest that psychopaths as defined by the PCL-R includes distinct subtypes, distinguishable in terms of personality structure, that may reflect different etiologies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A new active position sensing method for ropeless elevator

Traditional cable driven elevators perform poorly in high-rise buildings because the weight of the cable limits the payload, and its elasticity degrades control performance. Further, it is not mechanically possible to include several elevator cars in the same hoistway because of the cable. However such multi-car elevator systems are desirable since they reduce passenger waiting time and reduce the space requirements of the elevator system. A promising solution is to use long armature linear motors spanning the hoistway to directly drive elevator cages. In such applications, the mover position sensing method must be explicitly addressed since most active position sensing methods require traveling cables, which are also an obstacle for multi-car elevator systems.In this paper, the linear-motor active position sensing method is formally introduced and the principle of operation, design and real-time operation methods are presented. The proposed method is used to measure the position of the mover of a long armature permanent magnet linear synchronous motor requiring no active components on the mover, thus traveling cables are eliminated. The principle of operation is inspired by linear variable differential transformer: A magnetic shunt positioned at a fixed distance ahead of the mover deforms the magnetic field created by one of the armature coils. The deformation can be determined by measuring the induced voltages on the neighboring coils, and the position of the shunt, and thus the mover, can be calculated.A design method for the optimal dimensions of the shunt for a given armature to provide long measurement range and small maximum position error is presented, accompanied by a real-time measurement algorithm that will enable the motor to be driven using the method. Finally the method is verified by simulations and experimental results conducted on a full scale linear-motor elevator prototype that was constructed in the laboratory.     

Correction to Markon et al. (2011).

Reports an error in "The reliability and validity of discrete and continuous measures of psychopathology: A quantitative review" by Kristian E. Markon, Michael Chmielewski and Christopher J. Miller (Psychological Bulletin, 2011[Sep], Vol 137[5], 856-879). In the Samples section of Meta-Analysis 1: Reliability, third paragraph, the number of studies reporting data on clinical samples is incorrect. The sentence “Four studies included clinical samples, and eight studies included nonclinical samples” should read “Twenty-four studies included clinical samples, and eight studies included nonclinical samples.” (The following abstract of the original article appeared in record 2011-09705-001.) In 2 meta-analyses involving 58 studies and 59,575 participants, we quantitatively summarized the relative reliability and validity of continuous (i.e., dimensional) and discrete (i.e., categorical) measures of psychopathology. Overall, results suggest an expected 15% increase in reliability and 37% increase in validity through adoption of a continuous over discrete measure of psychopathology alone. This increase occurs across all types of samples and forms of psychopathology, with little evidence for exceptions. For typical observed effect sizes, the increase in validity is sufficient to almost halve sample sizes necessary to achieve standard power levels. With important caveats, the current results, considered with previous research, provide sufficient empirical and theoretical basis to assume a priori that continuous measurement of psychopathology is more reliable and valid. Use of continuous measures in psychopathology assessment has widespread theoretical and practical benefits in research and clinical settings. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

A Double-Deck Elevator Group Supervisory Control System Using Genetic Network Programming

Elevator group supervisory control systems (EGSCSs) are designed so that the movement of several elevators in a building is controlled efficiently. The efficient control of EGSCSs using conventional control methods is very difficult due to its complexity, so it is becoming popular to introduce artificial intelligence (AI) technologies into EGSCSs in recent years. As a new approach, a graph-based evolutionary method named genetic network programming (GNP) has been applied to the EGSCSs, and its effectiveness is clarified. The GNP can introduce various a priori knowledge of the EGSCSs in its node functions easily, and can execute an efficient rule-based group supervisory control that is optimized in an evolutionary way. Meanwhile, double-deck elevator systems (DDESs) where two cages are connected in a shaft have been developed for the rising demand of more efficient transport of passengers in high-rise buildings. The DDESs have specific features due to the connection of cages and the need for comfortable riding; so its group supervisory control becomes more complex and requires more efficient group control systems than the conventional single-deck elevator systems (SDESs). In this paper, a new group supervisory control system for DDESs using GNP is proposed, and its optimization and performance evaluation are done through simulations. First, optimization of the GNP for DDSEs is executed. Second, the performance of the proposed method is evaluated by comparison with conventional methods, and the obtained control rules in GNP are studied. Finally, the reduction of space requirements compared with SDESs is confirmed.     

The Photo Archives of the United States Holocaust Memorial Museum

Abstract

The primary function of the United States Holocaust Memorial Museum is educational. Its secondary role, no less important, is to preserve and record the history of the Holocaust for future generations. In this regard, the collection and preservation of photographs, textual records and artefacts that enable us to study this tragic period are of paramount importance. ‘After Daguerre, every man's family acquired a visual past: a tangible link with the history of the species’, wrote John Szarkowski in Looking at Photographs.¹ Now, after many years of dogged collecting, the ‘family’ of Holocaust survivors has a heavily documented visual past lodged at the US Holocaust Memorial Museum. Established in 1989, the photo archive of the Museum now counts 60 000 photographs in its roster. The photographs document Jewish life throughout the world before the Second World War, as well as the history of the persecution and extermination of Europe's Jews as well as non-Jewish victims. It is one of the largest such repositories in the world and one which historians, journalists and researchers ask to use every day.     

A cross-cultural study of the structure of comorbidity among common psychopathological syndromes in the general health care setting.

This study presents analyses of 7 common psychopathological syndromes in the World Health Organization (WHO) Collaborative Study of Psychological Problems in General Health Care (T. B. Ustun & N. Sartorius, 1995). Data on depression, somatization, hypochondriasis, neurasthenia, anxious worry, anxious arousal, and hazardous use of alcohol were analyzed for 14 countries (Ns for each country ranged from 196 to 800). Four models were evaluated: a 1-factor model; a 2-factor model in which all syndromes except hazardous use of alcohol represented internalizing problems; and two 3-factor models. The 2-factor model fit best. These results extend previous research on the 2-factor model to the current complaints of attendees of general health care clinics, to a new set of syndromes, and to a variety of both Western and non-Western countries. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The reliability and validity of discrete and continuous measures of psychopathology: A quantitative review.

[Correction Notice: An erratum for this article was reported in Vol 137(6) of Psychological Bulletin (see record 2011-24066-002). In the Samples section of Meta-Analysis 1: Reliability, third paragraph, the number of studies reporting data on clinical samples is incorrect. The sentence “Four studies included clinical samples, and eight studies included nonclinical samples” should read “Twenty-four studies included clinical samples, and eight studies included nonclinical samples.”] In 2 meta-analyses involving 58 studies and 59,575 participants, we quantitatively summarized the relative reliability and validity of continuous (i.e., dimensional) and discrete (i.e., categorical) measures of psychopathology. Overall, results suggest an expected 15% increase in reliability and 37% increase in validity through adoption of a continuous over discrete measure of psychopathology alone. This increase occurs across all types of samples and forms of psychopathology, with little evidence for exceptions. For typical observed effect sizes, the increase in validity is sufficient to almost halve sample sizes necessary to achieve standard power levels. With important caveats, the current results, considered with previous research, provide sufficient empirical and theoretical basis to assume a priori that continuous measurement of psychopathology is more reliable and valid. Use of continuous measures in psychopathology assessment has widespread theoretical and practical benefits in research and clinical settings. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Externalizing psychopathology in adulthood: A dimensional-spectrum conceptualization and its implications for DSM-V.

Mental disorders involving antisocial behavior and substance use are genetically linked and vary continuously. The authors present a review and integrative conceptualization of these observations in terms of a dimensional and hierarchically organized externalizing spectrum. As a foundation for this conceptualization, the authors introduce a quantitative, model-based approach to comparing categorical and continuous conceptions of psychopathology and apply this approach in an empirical study of patterns of comorbidity among externalizing disorders as defined in the Diagnostic and Statistical Manual of Mental Disorders. The authors present evidence that comorbidity among externalizing disorders is best modeled by an underlying normally distributed continuum of risk for multiple disorders within the externalizing spectrum. The authors conclude by discussing implications of the externalizing spectrum conceptualization for classification of disorders in the upcoming 5th edition of the Diagnostic and Statistical Manual of Mental Disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Information-theoretic latent distribution modeling: Distinguishing discrete and continuous latent variable models.

Distinguishing between discrete and continuous latent variable distributions has become increasingly important in numerous domains of behavioral science. Here, the authors explore an information-theoretic approach to latent distribution modeling, in which the ability of latent distribution models to represent statistical information in observed data is emphasized. The authors conclude that loss of statistical information with a decrease in the number of latent values provides an attractive basis for comparing discrete and continuous latent variable models. Theoretical considerations as well as the results of 2 Monte Carlo simulations indicate that information theory provides a sound basis for modeling latent distributions and distinguishing between discrete and continuous latent variable models in particular. (PsycINFO Database Record (c) 2010 APA, all rights reserved)