Intelligent structuring and reducing of association rules with formal concept analysis

Association rules are used to investigate large databases. The analyst is usually confronted with large lists of such rules and has to find the most relevant ones for his purpose. Based on results about knowledge representation within the theoretical framework of Formal Concept Analysis, we present relatively small bases for association rules from which all rules can be deduced. We also provide algorithms for their calculation.

Efficient data mining based on formal concept analysis

Formal Concept Analysis is an unsupervised learning technique for conceptual clustering. We introduce the notion of iceberg concept lattices and show their use in Knowledge Discovery in Databases (KDD). Iceberg lattices are designed for analyzing very large databases. In particular they serve as a condensed representation of frequent patterns as known from association rule mining. In order to show the interplay between Formal Concept Analysis and association rule mining, we discuss the algorithm TITANIC. We show that iceberg concept lattices are a starting point for computing condensed sets of association rules without loss of information, and are a visualization method for the resulting rules.

Conceptual knowledge processing with formal concept analysis and ontologies

Among many other knowledge representations formalisms, Ontologies and Formal Concept Analysis (FCA) aim at modeling ‘concepts’. We discuss how these two formalisms may complement another from an application point of view. In particular, we will see how FCA can be used to support Ontology Engineering, and how ontologies can be exploited in FCA applications. The interplay of FCA and ontologies is studied along the life cycle of an ontology: (i) FCA can support the building of the ontology as a learning technique. (ii) The established ontology can be analyzed and navigated by using techniques of FCA. (iii) Last but not least, the ontology may be used to improve an FCA application.

Ontology merging with formal concept analysis

Ontologies have been established for knowledge sharing and are widely used as a means for conceptually structuring domains of interest. With the growing usage of ontologies, the problem of overlapping knowledge in a common domain becomes critical. In this short paper, we address two methods for merging ontologies based on Formal Concept Analysis: FCA-Merge and ONTEX. --- FCA-Merge is a method for merging ontologies following a bottom-up approach which offers a structural description of the merging process. The method is guided by application-specific instances of the given source ontologies. We apply techniques from natural language processing and formal concept analysis to derive a lattice of concepts as a structural result of FCA-Merge. The generated result is then explored and transformed into the merged ontology with human interaction. --- ONTEX is a method for systematically structuring the top-down level of ontologies. It is based on an interactive, top-down- knowledge acquisition process, which assures that the knowledge engineer considers all possible cases while avoiding redundant acquisition. The method is suited especially for creating/merging the top part(s) of the ontologies, where high accuracy is required, and for supporting the merging of two (or more) ontologies on that level.

Efficient mining of association rules based on formal concept analysis

Association rules are a popular knowledge discovery technique for warehouse basket analysis. They indicate which items of the warehouse are frequently bought together. The problem of association rule mining has first been stated in 1993. Five years later, several research groups discovered that this problem has a strong connection to Formal Concept Analysis (FCA). In this survey, we will first introduce some basic ideas of this connection along a specific algorithm, TITANIC, and show how FCA helps in reducing the number of resulting rules without loss of information, before giving a general overview over the history and state of the art of applying FCA for association rule mining.

Algorithmic Computation of Formal Fourier Series

KAAD (Katholischer Akademischer Ausländer-Dienst)

Nitrogen requirements of cassava in selected soils of Thailand

Cassava (Manihot esculenta) is one of the most important export crops in Thailand, yet the nitrogen requirement is unknown and not considered by growers and producers. Cassava requirements for N were determined in field experiments during a period of four years and four sites on the Satuk (Suk), Don Chedi (Dc), Pak Chong (Pc),and Ban Beung (BBg) soil series in Lopburi, Supanburi, Nakhon Ratchasima, and Chonburi sites, respectively. The fertilizer treatment structure comprised 0, 62.5, 125, 187.5, 250 and 312.5 kg N ha^(-1) as urea. At each site cassava was harvested at nine months and yield parameters and the minimum datasets were taken. The fertilizer rate which resulted in maximum yield ranged from 187.5 kg N ha^(-1) in Supanburi and Chonburi (fresh weight yield of 47,500 and 30,000 kg ha^(-1) respectively) to 250 kg N ha^(-1) in Lopburi and Nakhon Ratchasima (fresh weight yield of 64,100 and 46,700 kg ha^(-1) respectively). Yield appeared to decrease at the higher, 312 kg ha^(-1), at Supanburi and Lopburi, and 250 kg ha^(-1) (Chonburi) fertilizer N rates. Net revenue was 70.4 and 72.9 % higher than where no N was appliedLopburi and Nakhon Ratchasima sites. Net revenue at the Supanburi and Chonburi sites were 53.8 and 211.0 % higher than that where no N was applied. This study suggests that at all sites improved cassava production and net revenue could be obtained with the judicious application of higher quantities of N. The results provide needed guidance to nitrogen fertilization of the important industrial crop cassava in Thailand.

Institutions, Behavior and Evolution

The three articles constituting this thesis are for reasons of content or method related to the following three fields in economics: Behavioral Economics, Evolutionary Game Theory and Formal Institutional Economics. A core element of these fields is the concept of individual preferences. Preferences are of central importance for the conceptional framework to analyze human behavior. They form the foundation for the theory of rational choice which is defined by the determination of the choice set and the selection of the most preferred alternative according to some consistency requirements. The theory of rational choice is based on a very simplified description of the problem of choice (object function and constraints). However, that choices depend on many more factors is for instance propagated by psychological theories and is supported by many empirical and experimental studies. This thesis adds to a better understanding of individual behavior to the extent that the evolution of certain characteristics of preferences and their consequences on human behavior forms the overarching theme of the dissertation. The long-term effect of evolutionary forces on a particular characteristic of importance in the theoretical, empirical and experimental economic literature, the concept of inequality aversion, is subject of the article “The evolution of inequality aversion in a simplified game of life” (Chapter 4). The contribution of the article is the overcoming of a restriction of former approaches to analyze the evolution of preferences in very simple environments. By classifying human interaction into three central economic games, the article provides a first step towards a simplified and sufficiently complete description of the interaction environment. Within such an environment the article characterizes the evolutionary stable preference distribution. One result shows, that the interaction of the aforementioned three classes can stabilize a preference of inequality aversion in the subpopulation which is favored in the problem of redistribution. The two remaining articles are concerned with social norms, which dissemination is determined by medium-run forces of cultural evolution. The article “The impact of market innovations on the evolution of social norms: the sustainability case.“ (Chapter 2) studies the interrelation between product innovations which are relevant from a sustainability perspective and an according social norm in consumption. This relation is based on a conformity bias in consumption and the attempt to avoid cognitive dissonances resulting from non-compliant consumption. Among others, it is shown that a conformity bias on the consumption side can lead to multiple equilibria on the side of norm adoption. The article “Evolution of cooperation in social dilemmas: signaling internalized norms.” (Chapter 3) studies the emergence of cooperation in social dilemmas based on the signaling of social norms. The article provides a potential explanation of cooperative behavior, which does not rely on the assumption of structured populations or on the unmotivated ability of social norms to restrict individual actions or strategy spaces. A comprehensive result of the single articles is the explanation of the phenomenon of partial norm adaption or dissemination of preferences. The plurality of the applied approaches with respect to the proximity to the rational choice approach and regarding the underlying evolutionary mechanics is a particular strength of the thesis. It shows the equality of these approaches in their potential to explain the phenomenon of cooperation in environments that provide material incentives for defective behavior. This also points to the need of a unified framework considering the biological and cultural coevolution of preference patterns.

Formal Multilevel Hierarchical Verification of Synchronous MOS Circuits

I have designed and implemented a system for the multilevel verification of synchronous MOS VLSI circuits. The system, called Silica Pithecus, accepts the schematic of an MOS circuit and a specification of the circuit's intended digital behavior. Silica Pithecus determines if the circuit meets its specification. If the circuit fails to meet its specification Silica Pithecus returns to the designer the reason for the failure. Unlike earlier verifiers which modelled primitives (e.g., transistors) as unidirectional digital devices, Silica Pithecus models primitives more realistically. Transistors are modelled as bidirectional devices of varying resistances, and nodes are modelled as capacitors. Silica Pithecus operates hierarchically, interactively, and incrementally. Major contributions of this research include a formal understanding of the relationship between different behavioral descriptions (e.g., signal, boolean, and arithmetic descriptions) of the same device, and a formalization of the relationship between the structure, behavior, and context of device. Given these formal structures my methods find sufficient conditions on the inputs of circuits which guarantee the correct operation of the circuit in the desired descriptive domain. These methods are algorithmic and complete. They also handle complex phenomena such as races and charge sharing. Informal notions such as races and hazards are shown to be derivable from the correctness conditions used by my methods.

Familia y educación formal : implicación de la familia en el proceso de enseñanza-aprendizaje.

Examinar la importancia que concede la familia, padres e hijos, a la Educación Formal. Para ello analiza la implicación de los padres en el proceso de enseñanza-aprendizaje de los hijos explorando su conducta en algunas variables de proceso familiar relativas al estudio y sondea, al mismo tiempo, la conducta que los hijos esperan de ellos. Pretende identificar aspectos de proceso familiar relativos al estudio donde padres e hijos muestren concordancia y discrepancia. Alumnos de séptimo de EGB y sus padres de 4 centros públicos de Oviedo, de dos zonas diferenciadas de la ciudad, elegidos dentro de cada zona según la posibilidad de acceso a los mismos, por lo que la muestra no es aleatoria. El número de alumnos fue el de dos aulas pero no siempre fueron los mismos sujetos en las tres aplicaciones del cuestionario. Variables procesuales (intereses, comportamientos) y evaluativas-perceptivas (actitudes, expectativas, percepciones) relativas al estudio, examinadas en padres y en hijos que, en conjunto, informan sobre las formas de implicación de los padres en el proceso de enseñanza-aprendizaje de los hijos y las formas de implicación de los padres esperadas por los hijos en dicho proceso. Variables de clasificación de dos tipos: estructurales como el nivel de estudios de los padres y de producto como el rendimiento escolar. Cuestionario ad hoc y entrevistas semiestructuradas a padres, con preguntas sobre intereses, actitudes, opiniones y expectativas. Los padres mantienen un nivel de implicación considerable sobre todo en las cuestiones referidas a actitudes, comportamiento que es esperado por los hijos. No todos los hijos esperan que sus padres se impliquen en aspectos de tipo afectivo y material del modo tan frencuente en que los hacen. A pesar de la coincidencia entre ellos, hay variables en las que los hijos esperan mayor implicación que el mostrado por sus padres como en aspectos relacionales, control del estudio diario, etc. La tipología de las variables relevantes en ambos colectivos, los aspectos intelectuales-culturales, cognitivo-perceptivos y de estatus son los mas asociados al rendimiento escolar. Padres e hijos conceden un gran valor a la educación formal. Ello lleva a los padres a implicarse en el proceso de enseñanza-aprendizaje y a los hijos a demandar esa implicación. Las formas de implicación suelen ser comunes entre padres e hijos por lo que se podría hablar de pautas de conducta configuradas en un contexto social, e incluso de pautas de conducta familiar. A la vista de los resultados se ofrece una serie de orientaciones y prácticas educativas que pueden ser relevantes para profesores, padres o alumnos.

Nonlinear Device Noise Models:Thermodynamic Requirements

This paper proposes three tests to determine whether a given nonlinear device noise model is in agreement with accepted thermodynamic principles. These tests are applied to several models. One conclusion is that every Gaussian noise model for any nonlinear device predicts thermodynamically impossible circuit behavior: these models should be abandoned. But the nonlinear shot-noise model predicts thermodynamically acceptable behavior under a constraint derived here. Further, this constraint specifies the current noise amplitude at each operating point from knowledge of the device v - i curve alone. For the Gaussian and shot-noise models, this paper shows how the thermodynamic requirements can be reduced to concise mathematical tests involving no approximatio

Material didáctico de educación ambiental no formal para el programa “yo, sí puedo cuidar el ambiente”, en Nicaragua

El presente trabajo ha consistido en elaborar el material didáctico para la educación ambiental no formal de los ciudadanos de Nicaragua, con nivel escolar equivalente a sexto grado. Este material en un futuro cercano será la base del programa de alfabetización ambiental “Yo, Sí Puedo Cuidar el Ambiente”,coordinado por la “Red Universitaria Yo, Sí Puedo” en distintas partes de Nicaragua. El resultado del proyecto es una cartilla destinada al alumno y una Guía Metodológica para el educador. Para la realización de este proyecto ha sido necesaria una estancia de tres meses y medio para la recopilación de información y la elaboración de material didáctico. El principal objetivo del material elaborado es contribuir en la sensibilización y la formación de valotres ambientales de los participantes, mejorando asi su calidad de vida y su entorno

How to improve the formal analytic reasoning and scientific motivation in the intellectual training of medical students

A review article of the The New England Journal of Medicine refers that almost a century ago, Abraham Flexner, a research scholar at the Carnegie Foundation for the Advancement of Teaching, undertook an assessment of medical education in 155 medical schools in operation in the United States and Canada. Flexner’s report emphasized the nonscientific approach of American medical schools to preparation for the profession, which contrasted with the university-based system of medical education in Germany. At the core of Flexner’s view was the notion that formal analytic reasoning, the kind of thinking integral to the natural sciences, should hold pride of place in the intellectual training of physicians. This idea was pioneered at Harvard University, the University of Michigan, and the University of Pennsylvania in the 1880s, but was most fully expressed in the educational program at Johns Hopkins University, which Flexner regarded as the ideal for medical education. (...)

Educaci??n formal, no formal e informal en el Espacio Europeo : nuevas exigencias para los procesos de formaci??n en educaci??n

Resumen tomado de la publicaci??n

El Aprendizaje del derecho inglés en modo cooperativo formal

En primer curso de Derecho económico de la Universidad de Vigo, se planteó la posibilidad de llevar a cabo un proyecto piloto de aprendizaje cooperativo. Nos pareció interesante la idea y propusimos que la asignatura “Introducción a los Sistemas Jurídicos” se impartiese en aprendizaje cooperativo formal, como requisito previo a la realización de un examen final. Nuestro objetivo era conseguir una mayor implicación del discente en su propio proceso de aprendizaje, al mismo tiempo que la adquisición de determinadas destrezas necesarias en el ámbito jurídico, como la interacción cara a cara, la interdependencia positiva, la responsabilidad personal, el saber desenvolverse en público y la capacidad de autoanálisis o evaluación de los resultados del grupo. En este caso concreto, era necesario dotar de las destrezas necesarias a los discentes para que el aprendizaje del Derecho Inglés, como sistema jurídico diferente al nuestro, resultase atractivo y suscitase el interés de los estudiantes a la hora de abordar el conocimiento del Common Law. La diferencia fundamental, reflejada en "Judge made Law", en referencia a la labor creadora del derecho que realizan los jueces en el mundo jurídico anglosajón, puede ser explicada mucho mejor en un contexto de creatividad como el que ofrece una metodología docente activa como es el Aprendizaje Cooperativo, y por ello resultó elegida. Elegimos el Aprendizaje Cooperativo Formal porque nos pareció adecuada su vocación de continuidad, en el sentido de formar grupos para una determinada tarea que puede durar desde una clase a varias semanas. En un grupo formal los estudiantes trabajan juntos para conseguir objetivos compartidos, intentando maximizar su aprendizaje y el de sus propios compañeros. El número de miembros que conforman un grupo formal es pequeño, 2 o 4 estudiantes, organizado por el profesor, a menudo al azar, y en ellos se espera que el estudiante interaccione con sus compañeros, compartiendo los conceptos y estrategias que aprendan, y que se consideren mutuamente responsables de la tarea asignada, acudiendo sólo en último término al profesor en caso de dudas. Pero teníamos dudas con respecto a la realidad del proyecto, por el elevado número de estudiantes en el grupo de “Introducción a los Sistemas Jurídicos”. Con todo, la ilusión y un gran esfuerzo hicieron posible llevar a cabo el proyecto previsto, y los resultados fueron totalmente positivos