Learning and Revising User Profiles: The Identification of Interesting Web Sites

We discuss algorithms for learning and revising user profiles that can determine which World Wide Web sites on a given topic would be interesting to a user. We describe the use of a naive Bayesian classifier for this task, and demonstrate that it can incrementally learn profiles from user feedback on the interestingness of Web sites. Furthermore, the Bayesian classifier may easily be extended to revise user provided profiles. In an experimental evaluation we compare the Bayesian classifier to computationally more intensive alternatives, and show that it performs at least as well as these approaches throughout a range of different domains. In addition, we empirically analyze the effects of providing the classifier with background knowledge in form of user defined profiles and examine the use of lexical knowledge for feature selection. We find that both approaches can substantially increase the prediction accuracy.     

Initial Stages in the Metal-dusting Process on Alloy 800

The initial stages of the metal-dusting process on Alloy 800 at 620 °C were investigated by light optical microscopy, RAMAN spectroscopy, atomic-force microscopy, Auger electron spectroscopy, transmission-electron microscopy and electron back-scatter diffraction. As it turned out the incubation period for metal-dusting is characterized by simultaneous formation of a heterogeneously growing oxide scale and deposition of carbon. The material surface shows different tarnish colors depending on the substrate-grain orientation with different susceptibility to the beginning of metal-dusting attack. “Low-index” grains were not attacked within the times investigated while the other grain orientations showed pitting. Carbon is evidently incorporated into the oxide scale from the very beginning of exposure with different intensities depending on the underlying substrate-grain orientation leading to differences in the tarnish colors. As a consequence carbides are formed even underneath “dense” oxide layers. Evidently metal-dusting attack starts at positions of the oxide scale where “higher carbon concentrations” are present.     

Effect of trichloroethylene on the exploratory and locomotor activity of rats exposed during development

Trichloroethylene (TCE) is a common contaminant of underground water supplies. To examine the effect of TCE on the developing central nervous system, rats were exposed to TCE throughout gestation until 21 days postpartum via their dams' drinking water. TCE concentrations of 312 mg/l, 625 mg/l and 1250 mg/l were tested. Exploratory behavior was higher in 60- and 90-day old male rats which were exposed to any level of TCE. The effect of TCE-exposure on locomotor activity (running wheel) was also examined in 60-day old males (625 and 1250 ppm exposure groups). Locomotor activity was significantly higher in rats exposed to 1250 ppm TCE. These data suggest that TCE has long-term effects on behaviour.     

Older and younger adults' attributions of responsibility toward rape victims and rapists.

Examined the judgments made by 384 undergraduates and 384 50–74 yr olds of assailant and victim responsibility for a sexual assault. Ss were assigned to 1 of 3 conditions: they viewed slides of an assault, read a passage about the crime, or read the passage and saw photographs of both the assailant and the victim. The rapist was presented as either a well-dressed or poorly dressed young man, and the victim appeared either as a provocative or demure young woman. Ss also learned that the victim either physically resisted or failed to resist the assailant. Young Ss attributed more responsibility to the assailant than did older Ss, and the provocative woman was perceived as more responsible for the victimization than the demure woman. Young Ss attributed greater responsibility to the victim when she resisted the assault of a well-dressed assailant than when she resisted a poorly dressed assailant. Females attributed less responsibility to the demure woman when she was assaulted by a poorly dressed assailant than a well dressed assailant. In contrast to older Ss, young Ss who visually observed the crime held the victim more responsible for her victimization. Results are interpreted in terms of the defensive attribution hypothesis of E. Walster (see record 1966-02829-001) and the discounting principle of attribution presented by H. H. Kelley (see record 1973-24800-001). (French abstract) (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Edward E. Jones (1926–1993): Obituary.

Memorializes E. E. Jones, whose early development of attribution theory, the actor–observer effect, and the correspondence bias as well as later work on self-handicapping, social stigma, and strategic self-presentation are central to modern social psychology. He built graduate programs at Duke and Princeton, trained many influential social psychologists, and received virtually every award in his field. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Varieties of working memory as seen in biology and in connectionist/control architectures

Biological and computational concepts that underlie the nature of working memory are briefly reviewed. The conceptualization of working memory has changed dramatically in the last 30 years. Current biological work has monitored several aspects of memory, including activation decay, sustained activation, long-term connection change, and differential structures for episodic (hippocampal formation) and procedural learning. Current connectionist modeling has identified factors including multiple-region-based processing, control processing as well as data storage, tradeoffs between fast- and slow-connection-change learning effects, and the speeding of acquisition via multiple levels of learning. The need to relate the biological, behavioral, and computational constraints into models of working memory is discussed. Finally, conceptualizations of working memory must acknowledge the need for human learning systems to be robust enough to operate in a dynamic world.     

Infants' predictive reaching for moving objects in the dark.

Infants were presented with a moving object under 2 lighting conditions to investigate the role of vision in early reaching. The motion of the target object also allowed for an analysis of the infants' ability to use a predictive style of reaching. Infants were tested twice, at 5 and 7.5 months of age, with a moving object in the light and the same object painted with luminescent paint in the dark. Infants successfully contacted the glowing object on about half of their attempts at both ages, although 7.5 month-olds reached more often. Infants also took into account the motion of the target object by aiming their reaches ahead of the object and by reaching with their contralateral hand. These results suggest that proprioceptive feedback and sight of the target allow for successful reaching with limited visual information, even in relatively complex reaching tasks. The infants' success also demonstrates their ability to adapt their movements and reaching strategy to the speed and trajectory of the target object in order to reach predictively. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

7.5 Gb/s monolithically integrated clock recovery circuit using PLLand 0.3-μm gate length quantum well HEMT's

A monolithically integrated clock recovery (CR) circuit making use of the phase-locked loop (PLL) circuit technique and enhancement/depletion AlGaAs/GaAs quantum well-high electron mobility transistors (QW-HEMT's) with gate lengths of 0.3 μm has been realized. A novel preprocessing circuit was used. In the PLL a fully-balanced varactorless VCO was applied. The VCO has a center oscillating frequency of about 7.7 GHz and a tuning range greater than 500 MHz. A satisfactory clock signal has been obtained at a bit rate of about 7.5 Gb/s. The power consumption is less than 200 mW at a supply voltage of -5 V     

Dislocations and flux pinning in YBa2Cu3O7

The dislocation structures of bulk textured and epitaxial thin film YBa₂Cu₃O₇ superconductors are examined. Correlations between increases in flux pinning and dislocation densities are noted. A model for flux pinning by individual dislocations is presented. This gives a treatment of strain induced effects and effects of normal state region interactions. It is shown that the values of pinning predicted are in line with experimental observations.     

Depressive symptomatology in maritally discordant women and men: The role of individual and relationship variables.

Marital discord and depressive symptomatology have repeatedly been found to be associated, but little is known about variables that influence this relationship. Data were collected from 139 couples seeking marital therapy, and analyses were conducted separately by gender. For wives, lower problem-solving ability, physical aggression by the partner, and 1 relationship belief predicted depressive symptomatology after the variance due to marital discord was removed in regression analyses. In addition to these predictors, less spouse-specific assertiveness, unemployment, and 1 other relationship belief were associated with depressive symptomatology for women after the variance due to marital discord was removed in partial correlation analyses. For men, only lower problem-solving ability added to the prediction of depressive symptomatology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)