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1.
This paper summarizes three lines of research that are motivated by the practical problem of helping users find information from external data sources, most notably computers. The application areas include information retrieval, text categorization, and question answering. A common theme in these applications is that practical information access problems can be solved by analyzing the statistical properties of words in large volumes of real world texts. The same statistical properties constrain human performance, thus we believe that solutions to practical information access problems can shed light on human knowledge representation and reasoning.  相似文献   
2.
In two studies (N’s = 515 and 359), we examine the utility of the Dual-Process Model of Self-Forgiveness for conceptualizing and measuring trait self-forgiveness with South African and American adults. Exploratory and confirmatory factor analyses of the trait-adapted Dual-Process Self-Forgiveness Scale supported an eight-item, two-factor structure of self-forgivingness consistent with prior theorizing and empirical evidence. The trait-adapted measure predicted incrementally more variance in outcomes beyond an existing measure of trait self-forgiveness. Latent subgroups characterized by tendencies to forgive, punish, and exonerate oneself in response to wrongdoing or failure were identified. Comparisons of mean differences provided preliminary evidence supporting the validity of the subgroups. Implications of the findings for conceptualizing and measuring self-forgiveness are discussed.  相似文献   
3.
In this paper, we organize past and present theories and models of creativity by using a new conceptual framework—the creativity matrix—with the aim of highlighting the dimensions of creativity we know a lot about and those we tend to either ignore or find difficult to study. This matrix is formed by bringing together a developmental model of creativity (the 4 C's) and a structural one (the 5 A's). We start by briefly describing these two conceptual frameworks, and then, we proceed to exploring the matrix itself by describing how the 5 A's are dynamically organized at each “level” of the 4 C's. Importantly, our overview of the matrix is informed by existing models and concepts that address one of more of the C's and the A's. This gives us a unique opportunity to take stock of what has been studied so far and, toward the end, consider new avenues for the development of theory and research agendas within creativity studies.  相似文献   
4.
Main clause phenomena (MCPs) are syntactic constructions that occur predominantly or exclusively in main clauses. I propose a processing explanation for MCPs. Sentence processing is easiest at the beginning of the sentence (requiring less search); this follows naturally from widely held assumptions about sentence processing. Because of this, a wider variety of constructions can be allowed at the beginning of the sentence without overwhelming the sentence‐processing mechanism. Unlike pragmatic and grammatical accounts of MCPs, the processing account predicts avoidance of MCPs in non‐initial main clauses (non‐initial coordinate clauses and premodified clauses). A corpus study supports these predictions, but it is somewhat inconclusive. A further corpus study examines another type of syntactic construction, premodifying adjunct phrases (“openers”); the prediction here is that less common types of opener will be especially avoided in non‐initial contexts. The prediction is confirmed, supporting the processing view of rare constructions.  相似文献   
5.
This study aims to investigate the effect of employee–supervisor political skill congruence on the quality of leader–member exchange (LMX), which in turn influences employees' job satisfaction and turnover intention. For this purpose, two survey studies were conducted. The first study examined the relationship between employee–supervisor political skill congruence and LMX using multi-source data collected from 287 employee–supervisor dyads. The second study examined the indirect effect of congruence in political skill on work outcomes through LMX by using time-lagged multi-source data collected from 142 employee–supervisor dyads. The findings indicate that compared with incongruence, congruence in political skill is associated with higher employee-rated LMX. Moreover, among dyads with congruent political skills, congruence at high levels of political skill is associated with higher employee-rated LMX compared with congruence at low levels of political skill. Moreover, in case of incongruency, low employee–high supervisor political skill combination was related to higher supervisor-rated LMX compared with high employee–low supervisor political skill combination. Lastly, employee–supervisor political skill congruency indirectly influences job satisfaction and turnover intention through employee-rated LMX. This research significantly contributes to the political skill literature by examining potential consequences of employee–supervisor congruence in political skill in the workplace.  相似文献   
6.
Although educational attainment has been identified as a significant factor that reduces uncritical positive attachment to one's country (i.e., blind patriotism), little is known about whether the remedial effect of education on uncritical patriotism is universal across countries with different histories of democratic rule. This article examines the extent to which democracy stock (the accumulated amount of democratic traditions, legacies, and experiences consolidated over time) conditions the relationship between education and blind patriotism. Using international data from 33 countries, the article shows that the remedial effect of education is more pronounced in countries with larger stocks of democracy than in countries with higher levels of democracy (current or recent). The results imply that the political socialization of critical patriotism is a cumulative process in which citizens internalize their potentially democratic competencies (e.g., knowledge, skills, and dispositions) and develop a sense of national attachment based on critical reflection on government policy and practice (i.e., critical loyalty) over an extended period of time.  相似文献   
7.
Pigeons and other animals soon learn to wait (pause) after food delivery on periodic-food schedules before resuming the food-rewarded response. Under most conditions the steady-state duration of the average waiting time, t, is a linear function of the typical interfood interval. We describe three experiments designed to explore the limits of this process. In all experiments, t was associated with one key color and the subsequent food delay, T, with another. In the first experiment, we compared the relation between t (waiting time) and T (food delay) under two conditions: when T was held constant, and when T was an inverse function of t. The pigeons could maximize the rate of food delivery under the first condition by setting t to a consistently short value; optimal behavior under the second condition required a linear relation with unit slope between t and T. Despite this difference in optimal policy, the pigeons in both cases showed the same linear relation, with slope less than one, between t and T. This result was confirmed in a second parametric experiment that added a third condition, in which T + t was held constant. Linear waiting appears to be an obligatory rule for pigeons. In a third experiment we arranged for a multiplicative relation between t and T (positive feedback), and produced either very short or very long waiting times as predicted by a quasi-dynamic model in which waiting time is strongly determined by the just-preceding food delay.  相似文献   
8.
A general model is developed for the analysis of multivariate multilevel data structures. Special cases of the model include repeated measures designs, multiple matrix samples, multilevel latent variable models, multiple time series, and variance and covariance component models.We would like to acknowledge the helpful comments of Ruth Silver. We also wish to thank the referees for helping to clarify the paper. This work was partly carried out with research funds provided by the Economic and Social Research Council (U.K.).  相似文献   
9.
Test theory without an answer key   总被引:2,自引:0,他引:2  
A general model is presented for homogeneous, dichotomous items when the answer key is not known a priori. The model is structurally related to the two-class latent structure model with the roles of respondents and items interchanged. For very small sets of respondents, iterative maximum likelihood estimates of the parameters can be obtained by existing methods. For other situations, new estimation methods are developed and assessed with Monte Carlo data. The answer key can be accurately reconstructed with relatively small sets of respondents. The model is useful when a researcher wants to study objectively the knowledge possessed by members of a culturally coherent group that the researcher is not a member of.This research was supported by NSF Grant No. SES-8320173 to the authors. We gratefully acknowledge comments and suggestions from John Boyd, Tarow Indow, and Kathy Maher as well as the editor and several anonymous referees.  相似文献   
10.
Canonical analysis of two convex polyhedral cones and applications   总被引:1,自引:0,他引:1  
Canonical analysis of two convex polyhedral cones consists in looking for two vectors (one in each cone) whose square cosine is a maximum. This paper presents new results about the properties of the optimal solution to this problem, and also discusses in detail the convergence of an alternating least squares algorithm. The set of scalings of an ordinal variable is a convex polyhedral cone, which thus plays an important role in optimal scaling methods for the analysis of ordinal data. Monotone analysis of variance, and correspondence analysis subject to an ordinal constraint on one of the factors are both canonical analyses of a convex polyhedral cone and a subspace. Optimal multiple regression of a dependent ordinal variable on a set of independent ordinal variables is a canonical analysis of two convex polyhedral cones as long as the signs of the regression coefficients are given. We discuss these three situations and illustrate them by examples.  相似文献   
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