Validating Automatically Generated Students’ Conceptual Models from Free-text Answers at the Level of Concepts

Evaluating a Bilingual Text-Mining System With a Taxonomy of Key Words and Hierarchical Visualization for Understanding Learner-Generated Text

“…Learner-generated text in this study refers to text generated from discussions and self-reflections in the learning process using features such as discussion forums in LMSs. Pérez-Marín and Pascual-Nieto (2010) studied the automatic generation of learners’ conceptual models using a hierarchical structure of domain knowledge with learner-generated text. Before constructing this conceptual model for each learner, domain knowledge and the related concepts were defined by the teacher, in which a set of questions per concept and the corresponding correct answers or references were provided by the teacher.…”

“…On the one hand, the above multilingual text-mining applications have focused on the development of automated techniques for information extraction, lexicon and key word extraction, and topic discovery from multilingual text. On the other hand, there are an increasing number of studies committed to show learners’ conceptual understanding through examining learner-generated text (Pérez-Marín & Pascual-Nieto, 2010; Lárusson & White, 2012; Dzikovska et al., 2014). However, the text-mining techniques attempting to understand conceptual model of learners are limited to text generated in a single language such as English only.…”

“…A bilingual taxonomy of key words is therefore adopted in this study to include a number of bilingual key words for each concept and subconcept for matching with text generated by the learners in order to comprehend their understanding of a domain. Referring to the work by Daems, Erkens, Malzahn, and Hoppe (2014) and Pérez-Marín & Pascual-Nieto (2010), the bilingual taxonomy adopted in this study sets a number of specific words and terms characterizing each concept and subconcept. When learners are asked to discuss their understanding of a domain, some of these key words will be covered in their elaborations of the related concepts and subconcepts of the domain.…”

“…This study focuses on exploring learners’ conceptual understanding of a domain and provides a domain-specific model from learner-generated text about their degree of proficiency in a domain. Some previous studies have presented the construction of conceptual models for identifying learners’ domain concepts covered by their text in English (Dzikovska, Steinhauser, Farrow, Moore, & Campbell, 2014; Pérez-Marín & Pascual-Nieto, 2010), in which a conceptual model may be specified by a concept map, conceptual diagram, hierarchical model, or other knowledge representation formats. In these models, each concept is represented by a set of predefined answers or references.…”