De la escuela infantil a la escuela primaria : ¿continuidad o ruptura en las matrices interactivas de la enseñanza y el aprendizaje?

Resumen tomado de la revista

Caracterización del conocimiento matemático para la enseñanza (MKT) de matrices en Bachillerato.

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El test de matrices progresivas de Raven : manual de aplicación y baremación española en preescolar y EGB.

Trabajo que recoge los resultados tras la aplicación del test de Raven en diferentes grupos de EGB para conocer de manera objetiva la realidad de los alumnos españoles de este nivel educativo. Todo ello va precedido por unas normas simplificadas de aplicación, acompañadas de las que dió el autor del test, y un estudio sintético y práctico de las variadas y diversas potencialidades del mismo encaminadas al conocimiento exhaustivo del examinando, así como diversas observaciones prácticas del autor..

Grafos e matrices. 'Gráficas y matrices'.

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Grafos e matrices. 'Grafos y matrices'.

Se introduce en el nuevo Bachillerato el tema 'grafos y matrices' cuyo objetivo principal es aportar una nueva justificación de la utilización de las matrices e introducir al alumno en la teoría de los grafos. Se hace una introducción a los elementos básicos de esta teoría definiendo brevemente algunos de ellos.

Introducción de las matrices de valoración analítica en el proceso de evaluación del Practicum de los Grados de Infantil y de Primaria.

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Reanalysis of perceptual confusion matrices

This paper presents a study reformatting and reanalyzing data collected in a 1955 study of the perception of sixteen different consonants in consonant-vowel combinations, by human listeners.

Big Decisions and Sparse Data: Adapting Scientific Publishing to the Needs of Practical Conservation

The biggest challenge in conservation biology is breaking down the gap between research and practical management. A major obstacle is the fact that many researchers are unwilling to tackle projects likely to produce sparse or messy data because the results would be difficult to publish in refereed journals. The obvious solution to sparse data is to build up results from multiple studies. Consequently, we suggest that there needs to be greater emphasis in conservation biology on publishing papers that can be built on by subsequent research rather than on papers that produce clear results individually. This building approach requires: (1) a stronger theoretical framework, in which researchers attempt to anticipate models that will be relevant in future studies and incorporate expected differences among studies into those models; (2) use of modern methods for model selection and multi-model inference, and publication of parameter estimates under a range of plausible models; (3) explicit incorporation of prior information into each case study; and (4) planning management treatments in an adaptive framework that considers treatments applied in other studies. We encourage journals to publish papers that promote this building approach rather than expecting papers to conform to traditional standards of rigor as stand-alone papers, and believe that this shift in publishing philosophy would better encourage researchers to tackle the most urgent conservation problems.

Determining nugget: sill ratios of standardized variograms from aerial photographs to krige sparse soil data

Maps of kriged soil properties for precision agriculture are often based on a variogram estimated from too few data because the costs of sampling and analysis are often prohibitive. If the variogram has been computed by the usual method of moments, it is likely to be unstable when there are fewer than 100 data. The scale of variation in soil properties should be investigated prior to sampling by computing a variogram from ancillary data, such as an aerial photograph of the bare soil. If the sampling interval suggested by this is large in relation to the size of the field there will be too few data to estimate a reliable variogram for kriging. Standardized variograms from aerial photographs can be used with standardized soil data that are sparse, provided the data are spatially structured and the nugget:sill ratio is similar to that of a reliable variogram of the property. The problem remains of how to set this ratio in the absence of an accurate variogram. Several methods of estimating the nugget:sill ratio for selected soil properties are proposed and evaluated. Standardized variograms with nugget:sill ratios set by these methods are more similar to those computed from intensive soil data than are variograms computed from sparse soil data. The results of cross-validation and mapping show that the standardized variograms provide more accurate estimates, and preserve the main patterns of variation better than those computed from sparse data.

Approximate factorization constraint preconditioners for saddle-point matrices

We consider the application of the conjugate gradient method to the solution of large, symmetric indefinite linear systems. Special emphasis is put on the use of constraint preconditioners and a new factorization that can reduce the number of flops required by the preconditioning step. Results concerning the eigenvalues of the preconditioned matrix and its minimum polynomial are given. Numerical experiments validate these conclusions.