José A. León

Intervention in Comprehension and Memory Strategies: Knowledge and Use of Text Structure.

Abstract A reading comprehension instructional programme was analyzed in two complementary studies. This programme was designed to improve knowledge and use of the text structure as a comprehension strategy. In the first empirical study, intervention was carried out through an instructional programme applied to a group of high school students (aged 14–15) at two different reading ability levels. The performance of good and poor readers was contrasted with the results obtained from two control groups. In general, the study indicated that the readers trained in this programme benefitted from improved text comprehension in comparison with their counterparts in the control groups. The aim of the second study was to determine if this improvement could be maintained with a different text structure. Thus, the question addressed was if the participants in the instructional programme transferred their newly acquired knowledge to a text with a structure which had not been previously taught. The results indicate that this is the case.

Latent Semantic Analysis Parameters for Essay Evaluation using Small-Scale Corpora*

Abstract Some previous studies (e.g. that carried out by Van Bruggen et al. in 2004) have pointed to a need for additional research in order to firmly establish the usefulness of LSA (latent semantic analysis) parameters for automatic evaluation of academic essays. The extreme variability in approaches to this technique makes it difficult to identify the most efficient parameters and the optimum combination. With this goal in mind, we conducted a high spectrum study to investigate the efficiency of some of the major LSA parameters in small-scale corpora. We used two specific domain corpora that differed in the structure of the text (one containing only technical terms and the other with more tangential information). Using these corpora we tested different semantic spaces, formed by applying different parameters and different methods of comparing the texts. Parameters varied included weighting functions (Log-IDF or Log-Entropy), dimensionality reduction (truncating the matrices after SVD to a set percentage of dimensions), methods of forming pseudo-documents (vector sum and folding-in) and measures of similarity (cosine or Euclidean distances). We also included two groups of essays to be graded, one written by experts and other by non-experts. Both groups were evaluated by three human graders and also by LSA. We extracted the correlations of each LSA condition with human graders, and conducted an ANOVA to analyse which parameter combination correlates best. Results suggest that distances are more efficient in academic essay evaluation than cosines. We found no clear evidence that the classical LSA protocol works systematically better than some simpler version (the classical protocol achieves the best performance only for some combinations of parameters in a few cases), and found that the benefits of reducing dimensionality arise only when the essays are introduced into semantic spaces using the folding-in method.

The effects of headlines and summaries on news comprehension and recall

In two experiments, we attempted to analyze the effects of newspaper article headlines and summaries on final comprehension and recall. During the first experiment, the participants consisted of 117 high school students from the 9th grade, 68 from the 11th grade, 79 first year Psychology students from the Autonoma University of Madrid and 66 fifth year Journalism students from the Complutense University of Madrid. The subjects were randomly required to read a news report in one of the following experimental conditions: (1) the whole news article (headline, summary and text), (2) the headline and text, (3) the summary and text, and (4), the text only. The data from immediate and delayed free recall tasks were recorded. The results showed that the structure of the news article did not influence the recall and that there were differences among groups in the amount and quality of recall. The headline and the summary modified by the use of macrostructural criteria constituted additional elements introduced into the second experiment to provide a contrast with the original headline and summary. The results showed that an improvement in article recall did occur with the modified version in comparison with the original version. These two experiments have confirmed that the aims and criteria of journalists differ from those held by the authors of scientific texts and question whether the reading strategies applied are the same in both cases.

Procesos inferenciales en la comprensión del discurso escrito: Infuencia de la estructura del texto en los procesos de comprensión

A traves de este trabajo se examinan diversas cuestiones relacionadas con los procesos de comprension y los tipos de texto o discurso escrito. El objetivo fundamental de este articulo es tratar de desvelar si el procesamiento que realiza el lector durante la comprension de un discurso determinado requiere de una actividad cognitiva diferente a cuando se trata de comprender otro de distinta naturaleza. Esta actividad cognitiva se identifica con la generacion de inferencias. Para ello, se analizan las diferencias existentes entre diversos tipos de texto, centrandonos fundamentalmente en el narrativo y el expositivo, analizando sus repercusiones sobre la cognicion humana. Se proponen diferencias en funcion del analisis de su naturaleza causal y de las inferencias que se generan cuando se comprenden

New algorithms assessing short summaries in expository texts using latent semantic analysis.

In this study, we compared four expert graders with latent semantic analysis (LSA) to assess short summaries of an expository text. As is well known, there are technical difficulties for LSA to establish a good semantic representation when analyzing short texts. In order to improve the reliability of LSA relative to human graders, we analyzed three new algorithms by two holistic methods used in previous research (León, Olmos, Escudero, Cañas, & Salmerón, 2006). The three new algorithms were (1) the semantic common network algorithm, an adaptation of an algorithm proposed by W. Kintsch (2001, 2002) with respect to LSA as a dynamic model of semantic representation; (2) a best-dimension reduction measure of the latent semantic space, selecting those dimensions that best contribute to improving the LSA assessment of summaries (Hu, Cai, Wiemer-Hastings, Graesser, & McNamara, 2007); and (3) the Euclidean distance measure, used by Rehder et al. (1998), which incorporates at the same time vector length and the cosine measures. A total of 192 Spanish middle-grade students and 6 experts took part in this study. They read an expository text and produced a short summary. Results showed significantly higher reliability of LSA as a computerized assessment tool for expository text when it used a best-dimension algorithm rather than a standard LSA algorithm. The semantic common network algorithm also showed promising results.

Intervención en estrategias de comprensión: un modelo basado en el conocimiento y aplicación de la estructura del texto

ResumenEn dos estudios complementarios se analizo la implantacion y posterior evaluacion de un programa de instruccion en alumnos con diferente grado de habilidad lectora. Este programa incidia basicamente en estrategias que requerian para su aplicacion un conocimiento expreso sobre la estructura del texto. En un primer estudio, los 72 alumnos de 1.° de BUP que tomaron parte (36 con buen nivel y 36 con un pobre nivel de comprension) se distribuyeron equitativamente en tres grupos: un grupo experimental y dos grupos control. A todos los grupos se aplicaron dos pruebas de recuerdo libre: inmediato y demorado (7 dias). Los resultados indicaron una mejora sustantiva de los lectores que fueron entrenados en este programa respecto a sus companeros homologos de los grupos control, en la comprension y recuerdo de la informacion relevante (macroestructura). En un segundo estudio, se evaluo el grado de transferencia de lo aprendido a situaciones nuevas. Los resultados indicaron que los sujetos entrenados en este pr...

Las inferencias en la comprensión e interpretación del discurso: Un análisis para su estudio e investigación

La realizacion de inferencias se considera actualmente una actividad tan imprescindible como compleja que media en los procesos de comprension del discurso. Dada la complejidad de su estudio, las inferencias han sido analizadas desde diferentes posiciones teoricas y metodologicas no siempre coincidentes. Al mismo tiempo, han surgido datos contradictorios, lo que ha generado importantes cuestiones aun no resueltas. Varias de estas cuestiones aluden a la naturaleza taxonomica de las inferencias, a como y cuando se generan y procesan, o que teoria de las propuestas predice y explica mejor su funcionamiento. En este trabajo abordaremos algunos de estos problemas centrandonos en el analisis de algunas teorias y sistemas de clasificacion propuestos por diferentes autores, asi como a las diferentes metodologias utilizadas debido fundamentalmente a la naturaleza interdisciplinar de su estudio. Como forma de solucionar estas limitaciones necesitamos de un modelo mas integrado que incluya un continuo de inferencias y que prediga inferencias en otros contextos distintos al narrativo, como son el periodistico y cientifico, a la vez que permita explicar mejor la interconectividad entre los procesos de comprension e inferencias.

La comprensión y recuerdo de textos expositivos a través del análisis de algunas variables del texto y lector

In the present study, we investigated the effects of the lexical and semantic complexity on the text comprehension and recall in different reader groups who differenciated in their comprehension and previous knowledge level about the topics of the text. Subjects were 48 «experts» (post-graduates students) and 96 «novices» (junior high school students), 48 good readers and 48 poor readers. All of the subjects read two expository texts at different levels of difficulty. Two recall tests were made, inmediate free recall and delayed free recall (seven days). The results demonstrated that this feature texts, complexi, of the text, were an essentuil factor in the comprehension, unce it decide the conduct of the different reader groups. So, althought the results in general demonstrated that the expert readers obtain the best scores, especially in the macrostructure, these results depend on the comprehension difficulty of the text.

La mejora de la comprensión lectora: un análisis interactivo

ResumenEl presente trabajo analiza, desde un enfoque interactivo, algunas caracteristicas del texto y del lector. Desde esta perspectiva se revisan algunos de los modelos de intervencion encaminados a facilitar en el sujeto el producto final de la comprension lectora. Como es sabido, esta intervencion puede introducirse tanto desde el mismo material escrito, a traves de tecnicas y recursos sobre planes de escritura que aplica el escritor, como desde las caracteristicas del lector, como es el conocimiento previo y el uso de estrategias lectoras mas eficaces en los sujetos. Desde esta ultima perspectiva incidimos especialmente en aquellos entrenamientos de estrategias encaminadas a potenciar un conocimiento y aplicacion de la estructura organizativa de los textos.

Transforming Selected Concepts Into Dimensions in Latent Semantic Analysis

This study presents a new approach for transforming the latent representation derived from a Latent Semantic Analysis (LSA) space into one where dimensions have nonlatent meanings. These meanings are based on lexical descriptors, which are selected by the LSA user. The authors present three analyses that provide examples of the utility of this methodology. The first analysis demonstrates how document terms can be projected into meaningful new dimensions. The second demonstrates how to use the modified space to perform multidimensional document labeling to obtain a high and substantive reliability between LSA experts. Finally, the internal validity of the method is assessed by comparing an original semantic space with a modified space. The results show high consistency between the two spaces, supporting the conclusion that the nonlatent coordinates generated using this methodology preserve the semantic relationships within the original LSA space.