scholarly journals Logic Grammars for Diagnosis and Repair

2003 ◽  
Vol 12 (03) ◽  
pp. 227-248 ◽  
Author(s):  
Henning Christiansen ◽  
Veronica Dahl

We propose an abductive model based on Constraint Handling Rule Grammars (CHRGs) for detecting and correcting errors in problem domains that can be described in terms of strings of words accepted by a logic grammar. We provide a proof of concept for the specific problem of detecting and repairing natural language errors, in particular, those concerning feature agreement. Our methodology relies on grammar and string transformation in accordance with a user-defined dictionary of possible repairs. This transformation also serves as top-down guidance for our essentially bottom-up parser. With respect to previous approaches to error detection and repair, including those that also use constraints and/or abduction, our methodology is surprisingly simple while far-reaching and efficient.

Author(s):  
SUNGHO KIM ◽  
GIJEONG JANG ◽  
WANG-HEON LEE ◽  
IN SO KWEON

This paper presents a combined model-based 3D object recognition method motivated by the robust properties of human vision. The human visual system (HVS) is very efficient and robust in identifying and grabbing objects, in part because of its properties of visual attention, contrast mechanism, feature binding, multiresolution and part-based representation. In addition, the HVS combines bottom-up and top-down information effectively using combined model representation. We propose a method for integrating these aspects under a Monte Carlo method. In this scheme, object recognition is regarded as a parameter optimization problem. The bottom-up process initializes parameters, and the top-down process optimizes them. Experimental results show that the proposed recognition model is feasible for 3D object identification and pose estimation.


2020 ◽  
Author(s):  
Laura Braun ◽  
Sven Rieger ◽  
Marion Spengler ◽  
Richard Göllner ◽  
Norman Rose ◽  
...  

The multidimensional, hierarchical model of self-concept by Shavelson, Hubner, and Stanton (1976) is a cornerstone of modern self-concept research. Given the comprehensive research interest in it, it is surprising that one core aspect of this model has yet to be clarified: What is the best way to operationalize the elusive construct of global self-concept as the apex of the hierarchy? Previous research implemented global self-concept by applying reflective modeling procedures (e.g., second-order factor models) that followed a top-down logic, which assumes that global self-concept affects lower order self-concepts. However, theoretical considerations have often equally emphasized bottom-up processes, in which lower order self-concepts form a global self-concept. Yet, a bottom-up approach has not garnered much empirical interest, most likely because the requisite statistical models have not been available. The recently proposed model-based latent composite score can fill this gap. Therefore, we contrasted top-down and bottom-up representations of global self-concept by comparing conventional second-order factors and model-based latent composite scores. Across three independent large-scale studies (Study 1: N = 8,063; Study 2: N = 3,081; Study 3: N = 2,106), the second-order factors reproduced only small amounts of interindividual differences, which boosted the correlations with external criteria (i.e., self-esteem, enjoyment of school, academic outcomes) to theoretically and somewhat empirically implausible levels. By contrast, the composite score showed a more plausible pattern of stabilities and correlations. We discuss the consequences of the two approaches and propose the latent composite score as a new perspective on the apex of the Shavelson model.


PsycCRITIQUES ◽  
2005 ◽  
Vol 50 (19) ◽  
Author(s):  
Michael Cole
Keyword(s):  
Top Down ◽  

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