Text mining with the WEBSOM

The emerging field of text mining applies methods from data mining and exploratory data analysis to analyzing text collections and to conveying information to the user in an intuitive manner. Visual, map-like displays provide a powerful and fast medium for portraying information about large collections of text. Relationships between text items and collections, such as similarity, clusters, gaps and outliers can be communicated naturally using spatial relationships, shading, and colors. In the WEBSOM method the self-organizing map (SOM) algorithm is used to automatically organize very large and high-dimensional collections of text documents onto two-dimensional map displays. The map forms a document landscape where similar documents appear close to each other at points of the regular map grid. The landscape can be labeled with automatically identified descriptive words that convey properties of each area and also act as landmarks during exploration. With the help of an HTML-based interactive tool the ordered landscape can be used in browsing the document collection and in performing searches on the map. An organized map offers an overview of an unknown document collection helping the user in familiarizing herself with the domain. Map displays that are already familiar can be used as visual frames of reference for conveying properties of unknown text items. Static, thematically arranged document landscapes provide meaningful backgrounds for dynamic visualizations of for example time-related properties of the data. Search results can be visualized in the context of related documents. Experiments on document collections of various sizes, text types, and languages show that the WEBSOM method is scalable and generally applicable. Preliminary results in a text retrieval experiment indicate that even when the additional value provided by the visualization is disregarded the document maps perform at least comparably with more conventional retrieval methods.reviewe

Word Sense Disambiguation in Document Space

We introduce a method for word sense disambiguation that uses an existing topical document map crated with an unsupervised method (WEBSOM) on a very large document collection. Results on the SENSEVAL-2 corpus indicate that the method is statistically significantly better than the baselins and on par with supervised methods. The method uses the document map as a representation of the semantic space of word contexts. The assumption is that similar meanings of a word have similar contexts, which are located in the same are on the self-organized document map. The results confirm this assumption. The benefi of the proposed method is that a single general purpose representation of the semantic space can be used for all words and their word senses.Peer reviewe

Yhteiskunnan laaja systeeminen murros haltuun

Viime vuosikymmeninä olemme yhteiskuntana käyneet läpi laajaa systeemistä murrosta. Digiajassa ja ennakoimattoman muutoksen keskelläkin on mahdollista rakentaa hyvää yhteiskuntaa, kun elämme aidossa vuorovaikutuksessa, nykytekniikan mahdollistamia tietovirtoja analysoiden. Kansalaisten omin sanoin sanoittamat kokemukset yhteiskunnasta ja sen palveluista tulisi ottaa keskiöön osana palveluiden ja prosessien arviointia ja kehittämistä. Tämä tulee mahdolliseksi big datan, tekoälyn ja tukiälyn menetelmien sekä avoimen tieteen ja tutkimuksen toimintakulttuurin avulla

Evaluating the effect of word frequencies in a probabilistic generative model of morphology

Proceedings of the 18th Nordic Conference of Computational Linguistics NODALIDA 2011. Editors: Bolette Sandford Pedersen, Gunta Nešpore and Inguna Skadiņa. NEALT Proceedings Series, Vol. 11 (2011), 230-237. © 2011 The editors and contributors. Published by Northern European Association for Language Technology (NEALT) http://omilia.uio.no/nealt . Electronically published at Tartu University Library (Estonia) http://hdl.handle.net/10062/16955

Morfessor and Hutmegs : Unsupervised Morpheme Segmentation for Highly-Inflecting and Compounding Languages

Peer reviewe

Transfer-Learning Methods in Programming Course Outcome Prediction

The computing education research literature contains a wide variety of methods that can be used to identify students who are either at risk of failing their studies or who could benefit from additional challenges. Many of these are based on machine-learning models that learn to make predictions based on previously observed data. However, in educational contexts, differences between courses set huge challenges for the generalizability of these methods. For example, traditional machine-learning methods assume identical distribution in all data—in our terms, traditional machine-learning methods assume that all teaching contexts are alike. In practice, data collected from different courses can be very different as a variety of factors may change, including grading, materials, teaching approach, and the students. Transfer-learning methodologies have been created to address this challenge. They relax the strict assumption of identical distribution for training and test data. Some similarity between the contexts is still needed for efficient learning. In this work, we review the concept of transfer learning especially for the purpose of predicting the outcome of an introductory programming course and contrast the results with those from traditional machine-learning methods. The methods are evaluated using data collected in situ from two separate introductory programming courses. We empirically show that transfer-learning methods are able to improve the predictions, especially in cases with limited amount of training data, for example, when making early predictions for a new context. The difference in predictive power is, however, rather subtle, and traditional machine-learning models can be sufficiently accurate assuming the contexts are closely related and the features describing the student activity are carefully chosen to be insensitive to the fine differences.Peer reviewe

Sosiaalitieteiden tiedon avoin saatavuus : Haasteita ja ratkaisuja

Peer reviewe

Lääketutka - Löytöretkeilyä ihmisten keskusteluihin omasta terveydestään

Peer reviewe

The interplay between cognitive, conative, and affective constructs along the entrepreneurial learning process

Purpose: Although the role of reflections in entrepreneurship education is undeniable, the research has focused mainly on their advantages and consequences for learning process, whereas their dynamics and interrelations with other mental processes remain unexplored. The purpose of this paper is to better understand how personality and intelligence constructs: cognition, conation, and affection evolve and change along the learning process during entrepreneurship education. Design/methodology/approach: To better understand reflective processes in entrepreneurial learning this paper adopts the tripartite constructs of personality and intelligence. By employing longitudinal explorative research approach and self-organizing map (SOM) algorithm, the authors follow students’ reflections during their two-year learning processes. First, the authors try to identify how the interplay between the cognitive, conative, and affective aspects emerges in students’ reflections. Then, the authors investigate how this interplay evolves during the individual learning process and finally, by looking for similarities in these learning pathways, the authors aim to identify patterns of students’ reflective learning process. Findings: All constructs are present during the learning process and all are prone to change. The individual constructs alone shed no light on the interplay between different constructs, but rather that the interplay between sub-constructs should be taken into consideration as well. This seems to be particularly true for cognition, as procedural and declarative knowledge have very different profiles. Procedural knowledge emerges together with emotions, motivation, and volition, whereas the profile of declarative knowledge is individual. The unique profile of declarative knowledge in students’ reflections is an important finding as declarative knowledge is regarded as the center of current pedagogic practices. Research limitations/implications The study broadens the understanding of reflective practices in the entrepreneurial learning process and the interplay between affective, cognitive, and conative sub-constructs and reflective practices in entrepreneurship education. The findings clearly indicate the need for further research on the interplay between sub-constructs and students’ reflection profiles. The authors see the study as an attempt to apply an exploratory statistical method for the problem in question. Practical implications: The results are able to advise pedagogy. Practical implications concern the need to develop reflective practises in entrepreneurial learning interventions to enhance all three meta-competencies, even though there are so far no irrefutable findings to indicate that some types of reflection may be better than others. Originality/value: The results of the analysis indicate that it is possible to study the complex and dynamic interplay between sub-constructs of cognitive, conative and affective constructs. Moreover, the research succeeded in identifying both individual variations and general reflection patterns and changes in these during the learning process. This was possible by adopting a longitudinal explorative research approach with SOM analyses.Peer reviewe