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41.
Query reformulation mining: models,patterns, and applications 总被引：1，自引：0，他引：1
Paolo Boldi Francesco Bonchi Carlos Castillo Sebastiano Vigna 《Information Retrieval》2011,14(3):257-289
Understanding query reformulation patterns is a key task towards next generation web search engines. If we can do that, then
we can build systems able to understand and possibly predict user intent, providing the needed assistance at the right time,
and thus helping users locate information more effectively and improving their web-search experience. As a step in this direction,
we build a very accurate model for classifying user query reformulations into broad classes (generalization, specialization,
error correction or parallel move), achieving 92% accuracy. We then apply the model to automatically label two very large
query logs sampled from different geographic areas, and containing a total of approximately 17 million query reformulations.
We study the resulting reformulation patterns, matching some results from previous studies performed on smaller manually annotated
datasets, and discovering new interesting reformulation patterns, including connections between reformulation types and topical
categories. We annotate two large query-flow graphs with reformulation type information, and run several graph-characterization
experiments on these graphs, extracting new insights about the relationships between the different query reformulation types.
Finally we study query recommendations based on short random walks on the query-flow graphs. Our experiments show that these
methods can match in precision, and often improve, recommendations based on query-click graphs, without the need of users’
clicks. Our experiments also show that it is important to consider transition-type labels on edges for having recommendations
of good quality. 相似文献
42.
Miguel Ángel Cano Linda G. Castillo Yessenia Castro Marcel A. de Dios Angelica M. Roncancio 《International journal for the advancement of counseling》2014,36(2):136-149
This study examined associations of intragroup marginalization and cultural incongruity with acculturative stress and depressive symptoms among 155 undergraduate U.S. college students of Mexican heritage. Findings indicate that perceived interpersonal distancing by the family (intragroup marginalization) and perceived lack of cultural fit between the respondent and academic institution (cultural incongruity) had statistically significant direct and indirect effects on depressive symptoms via acculturative stress. Results also show that 39.7 % of the variance corresponding with depressive symptoms was accounted for by intragroup marginalization, cultural incongruity, acculturative stress, and other exogenous variables. 相似文献
43.
Cristina Castillo 《Cultura y Educación》2013,25(1):125-157
AbstractClassroom interaction is a key element in the teaching-learning process. Our aim was to determine the impact of teaching practices, children’s initial knowledge of written language and children’s linguistic condition on the dynamics of classroom interactions in the course of reading and writing activities. We followed longitudinally 205 students from kindergarten to first grade and examined the interactions in which they took part according to the agents involved and the function interactions fulfilled. Results showed an increase in the frequency of interactions as school level increased. Teachers had a predominant role as interaction agents and teaching practices and students’ initial literacy knowledge had a significant impact on the distribution of the interactions. Monolingual students with non-instructional teachers and a high level of initial knowledge participated in a higher number of interactions than bilingual students with instructional teachers and a lower level of initial knowledge. We suggest encouraging peer interaction as a means of promoting knowledge construction processes. 相似文献
44.
Margaret O’Dougherty Wright Emily Crawford Darren Del Castillo 《Child abuse & neglect》2009,33(1):59-68
ObjectiveTheoretically, exposure to experiences of emotional abuse (EA) and emotional neglect (EN) in childhood may threaten the security of attachment relationships and result in maladaptive models of self and self-in-relation to others. The purpose of this study was to explore the extent to which EA and EN treatment by parents contributed uniquely to young adult maladaptive long-term outcome with respect to symptoms of anxiety, depression, and dissociation. The extent to which the relationships between EA and EN and later symptoms were mediated by specific internalized maladaptive interpersonal schemas was also explored.MethodsQuestionnaires completed by 301 college men and women (52% female) assessed perceptions of experiences of childhood abuse and neglect, exposure to parental alcoholism, current symptoms of psychological distress, and endorsement of maladaptive interpersonal schemas.ResultsHierarchical regression analyses revealed that perceptions of childhood EA and EN each continued to exert an influence on later symptoms after controlling for gender, income, parental alcoholism, and other child abuse experiences. Both EA and EN were associated with later symptoms of anxiety and depression and were mediated by schemas of vulnerability to harm, shame, and self-sacrifice. Only EN was related to later symptoms of dissociation; this relationship was mediated by the schemas of shame and vulnerability to harm.ConclusionThe findings are discussed from an attachment perspective, focusing on how early interactions with parents contribute to the development of internal working models of self and self-in-relation to others that influence later cognitive schemas and psychological adjustment.Practice implicationsAlthough emotional abuse and emotional neglect are the least studied of all forms of child maltreatment, they may be the most prevalent. The current findings suggest that how college students have evaluated and internalized these experiences may be even more important than the events themselves in determining the extent to which these experiences exert a long-term impact. For this reason, early intervention might be particularly important in helping to modify internal working models of the self as worthless, others as abusive, or the world as threatening and dangerous as a result of past abuse experiences. This study underscores the need for counselors to actively elicit and explore experiences of emotional abuse and neglect in clients, in addition to inquiring about other abuse experiences and types of family dysfunction.The results of this study also support existing data suggesting that internalized representational models of self and others are a key mechanism underlying the relationship between emotional maltreatment and later psychopathology. Young's schema questionnaire proved to be quite sensitive in detecting specific maladaptive schemas that mediated later difficulties with depression, anxiety, and dissociation. Targeting these negative schemas in therapy may help to ameliorate such symptoms. The therapeutic relationship provides a particularly effective context for developing more positive models of self and others, as well as providing a context to explore core relationship themes across different relationship contexts (e.g., intimate partner, parent, friend, and work relationships). In particular, if the assessment of the client reveals that dissociative symptoms are present, counselors can acknowledge the adaptive function that this strategy once served, while also addressing potential limitations to over-reliance on this coping strategy. 相似文献
45.
This paper deals with a supervised learning method devoted to producing categorization models of text documents. The goal
of the method is to use a suitable numerical measurement of example similarity to find centroids describing different categories
of examples. The centroids are not abstract or statistical models, but rather consist of bits of examples. The centroid-learning
method is based on a Genetic Algorithm for Texts (GAT). The categorization system using this genetic algorithm infers a model
by applying the genetic algorithm to each set of preclassified documents belonging to a category. The models thus obtained
are the category centroids that are used to predict the category of a test document. The experimental results validate the
utility of this approach for classifying incoming documents. 相似文献
46.
OBJECTIVE: Adaptation of the Multidimensional Trauma Recovery and Resilience (MTRR) in a Chilean sample. METHOD: Participants were 80 mothers drawn from two large metropolitan areas (Santiago and Temuco). Sample participants (in a case control design) were redivided in two groups: 40 mothers identified as physical abusers with history of physical child abuse and 40 mothers identified as nonabusers with history of physical child abuse. Groups were matched on 5 sociodemographic variables. Reliability analysis, item analysis, and group comparisons on the 8 scales of the instrument were performed. RESULTS: Interrater agreement level was .79 (Kendall's W coefficient) and the internal consistency as measured by Cronbach's alpha coefficient was .75. Twenty-five items (26.3%) significantly discriminated between the groups. Group comparison tests (Wilcoxon Rank-sum Test) also indicated that six of the eight domains discriminated between the groups. CONCLUSION: In our sample, the instrument has reliable results which discriminate between the studied groups. These preliminary findings support future work toward the development of a Chilean version of this instrument. 相似文献
47.
Alicia Castillo Salvador García-Ruvalcaba Luis M. Martínez R. 《Environmental Education Research》2002,8(4):395-411
Ecological research is expected to provide a scientific basis on which environmental management decisions can be taken. Environmental education is seen as raising environmental awareness among human populations and as a provider of the knowledge, values, attitudes and skills needed to protect the environment. This article proposes that in the context of developing countries such as Mexico, one role for environmental education is to facilitate the utilisation of ecological information in the solution of problems. In order to outline how this can work in practice, a case study is used to outline the role of environmental education as the linkage between science (its institutions, actors and products) and different sectors of society involved in the management of ecosystems, their resources and the services they provide. 相似文献
48.
Micaela F. Sousa-Rodrigues José P. Espada María T. Gonzálvez Mireia Orgilés 《Psychology in the schools》2020,57(11):1680-1688
Separation anxiety symptoms are very common in children. The present study aims to examine the psychometric properties and the factorial structure of the Portuguese version of the Separation Anxiety Scale for Children (SASC). The participants included 874 children, 52% male, aged between 8 and 11 years (M = 9.50; SD = 1.15). Factor analysis supported the three-factor model found in the original scale. The instrument demonstrated to have good reliability for the total score (α = .81) and for its three factors (Discomfort from separation, α = .80; Worry about separation, α = .72; Calm at separation, α = .59). The validity, examined via the correlation of the SASC with the separation anxiety subscale of the SCARED, was satisfactory (r = .49); the test–retest reliability for the total scale was good (r = .81). The SASC was shown to have good psychometric properties for its use with Portuguese children for clinical and research purposes. 相似文献
49.
Linda G. Castillo 《International journal for the advancement of counseling》2009,31(4):245-254
The purpose of this article is to examine how intragroup marginalization has a potential impact on Latino college students’
psychological adjustment. The concept of intragroup marginalization in this context relates to the perceived rejection of
students by persons of their heritage culture group in response to the students’ acculturation efforts in regard to the college
culture. Counselors can facilitate college success of Latino students by addressing acculturative stressors. Intragroup marginalization
and its relationship to Latino college student adjustment is illustrated and discussed through a vignette. 相似文献
50.
Mauro Cappelli Bernardino Castillo–Toledo Stefano Di Gennaro 《Journal of The Franklin Institute》2021,358(2):1308-1326
In this work, dynamic controllers are designed for reactor power, pressurizer water level, and pressure control in the primary circuit of a pressurized water reactor. These nonlinear controllers use super-twisting sliding-mode estimators to enhance their robustness versus parameter variations and external disturbances. Hence, the perturbative terms can be canceled by the control, thus improving the dynamic behavior of the controlled system. The designed controllers ensure good performances and better transient behavior, also in the presence of uncertainties and disturbances. A performance study of the proposed controllers is carried out in the presence also of unmodeled dynamics. 相似文献