Publications

What's in it for me? Augmenting Recommended Learning Resources with Navigable Annotations

This paper introduces an interface that enables the user to quickly identify relevant fragments within multiple long documents. The proposed method relies on a machine-generated layer of annotations that reveals the coverage of topics per fragment and document. To illustrate how the annotations double as a tool for preview as well as navigation, an example application is presented in the form of a personalised learning system that recommends relevant fragments of video lectures according to user’s history. Potential implications of this approach for lifelong learning are discussed. We argue that this approach is generally applicable to recommender and information retrieval systems, across multiple knowledge domains and document types.

TrueLearn: A Family of Bayesian Algorithms to Match Lifelong Learners to Open Educational Resources

The recent advances in computer-assisted learning systems and the availability of open educational resources today promise a pathway to providing cost-efficient, high-quality education to large masses of learners. One of the most ambitious use cases of computer-assisted learning is to build a lifelong learning recommendation system. Unlike short-term courses, lifelong learning presents unique challenges, requiring sophisticated recommendation models that account for a wide range of factors such as background knowledge of learners or novelty of the material while effectively maintaining knowledge states of masses of learners for significantly longer periods of time (ideally, a lifetime). This work presents the foundations towards building a dynamic, scalable and transparent recommendation system for education, modelling learner’s knowledge from implicit data in the form of engagement with open educational resources. We i) use a text ontology based on Wikipedia to automatically extract knowledge components of educational resources and, ii) propose a set of online Bayesian strategies inspired by the well-known areas of item response theory and knowledge tracing. Our proposal, TrueLearn, focuses on recommendations for which the learner has enough background knowledge (so they are able to understand and learn from the material), and the material has enough novelty that would help the learner improve their knowledge about the subject and keep them engaged. We further construct a large open educational video lectures dataset and test the performance of the proposed algorithms, which show clear promise towards building an effective educational recommendation system.

Towards an Integrative Educational Recommender for Lifelong Learners

One of the most ambitious use cases of computer-assisted learning is to build a recommendation system for lifelong learning. Most recommender algorithms exploit similarities between content and users, overseeing the necessity to leverage sensible learning trajectories for the learner. Lifelong learning thus presents unique challenges, requiring scalable and transparent models that can account for learner knowledge and content novelty simultaneously, while also retaining accurate learners representations for long periods of time. We attempt to build a novel educational recommender, that relies on an integrative approach combining multiple drivers of learners engagement. Our first step towards this goal is TrueLearn, which models content novelty and background knowledge of learners and achieves promising performance while retaining a human interpretable learner model.

SUM'20: State-based User Modelling

Capturing and effectively utilising user states and goals is becoming a timely challenge for successfully leveraging intelligent and usercentric systems in differentweb search and data mining applications. Examples of such systems are conversational agents, intelligent assistants, educational and contextual information retrieval systems, recommender/match-making systems and advertising systems, all of which rely on identifying the user state in order to provide the most relevant information and assist users in achieving their goals. There has been, however, limited work towards building such state-aware intelligent learning mechanisms. Hence, devising information systems that can keep track of the user’s state has been listed as one of the grand challenges to be tackled in the next few years [1]. It is thus timely to organize a workshop that re-visits the problem of designing and evaluating state-aware and user-centric systems, ensuring that the community (spanning academic and industrial backgrounds) works together to tackle these challenges.

Towards Automatic, Scalable Quality Assurance in Open Education

With the emergence of Open Education Resources (OERs), educational content creation has boomed to a whole new scale. For AI-driven OER platforms such as X5GON, scalable quality assurance is highly impactful. As the quality of OERs could vary significantly, the quality assurance process plays a key role in maintaining a high-quality learner experience when using OERs. Managing this problem at large scale demands automating the quality assurance process as a whole or in parts. Prior research on automating quality assurance in the context of education is surprisingly scarce. We present our ongoing work of building Quality Assurance Models, a novel approach to using crossmodal features from OERs to predict quality using machine learning. While developing quality models, we extended our search beyond the education domain to identify features that indicate content quality that can be categorised into five main quality verticals. In the future, these features will enable us to leverage scalable quality assurance on OERs of different modalities. Furthermore, quality features will also become useful in learning quality preferences of learners when recommending content. Altogether, the expected outcomes of this research will mark a significant step towards Automatic, Scalable Quality Assurance in Open Education.

An Analysis of Academic Performance of Undergraduates: Effects of Academic Vis-A-vis Non-Academic Factors

The objective of this study is to assess the extent to which academic history vis-à-vis other factors influence the academic performance of the undergraduate students in the Faculty of Agriculture, University of Peradeniya in Sri Lanka. A series of educational production functions were estimated treating Grade Point Average of students at semester level and cumulative Grade Point Average as the measures of academic performance. Academic history, engagements in student associations and other extra-curricular activities, learning environment, associations with the teaching staff, resources and support services provided by the university, social interactions, psychological factors, family background, funding and student inherent characteristics/personal background were hypothesized as the factors affecting academic performance. A structured questionnaire was distributed among 196 students in the final year of Agricultural Technology and Management degree program offered by the Faculty of Agriculture in 2011 to gather the needed data and 121 students responded to the survey. Results of the econometric models specified at semester levels reveal that during the first semester, English language proficiency, efforts made by the student and family background have positive and statistically significant effects on academic performance of undergraduates while the performance during semesters 2-7 is largely driven by the performance of the previous semester. A significant gender disparity in academic performance of undergraduates exists. In general, female students perform better than the male students and psychological factors explain a considerable proportion of the variability of academic performance. The results further reveal that the overall academic performance is influenced by the language proficiency and the academic efforts made by the students. Female students and those who came from privileged districts perform much better than their respective counterparts. Academic performance at school does not have a significant effect even when the other factors affecting undergraduate performance are controlled for. The study concludes that the English language proficiency, family background and academic efforts made by the students are the three key elements that determine the academic performance at every level. Contrary to the expectation, the performance at the Advanced Level examination, as measured by the Z score, does not seem to influence undergraduate academic performance in a statistically significant manner. The above findings imply a need to upgrade the facilities to improve English language proficiency and to create an enabling learning environment primarily through strengthening of social interactions and enhancing psychological spirits of undergraduates in order to obtain the best return for the investment made in higher education in Sri Lanka.

Efficiency of using Chemical Leasing approach in Pest and Disease control in Agriculture – Evidence from the Potato Cultivation

Chemical fertilization is very popular in Sri Lankan agriculture and application of chemicals has a major impact on the economy, health and environment of the country. Vegetable and home garden cultivation has recorded the most severe harm adding very high levels of heavy metals to the environment. Chemical Leasing is an innovative business model which is a good solution for this issue which will reduce chemical usage while maximizing profits to major stakeholders. During the study, chemical leasing approach was applied to potato cultivation parallel to conventional farming approach. The pytoprotection chemicals were reduced in the chemical leasing approach and the leaf area and height was used to measure plant growth. New software was developed to measure the plant leaf area more efficiently. A methodology is formulated to derive the unit of payment for chemical leasing. Results show that the new software based approach to measuring leaf area is very successful with both Average Absolute Error and Average Bias Error < 5%. It is very much suitable for developing countries as it is less expensive and less labour intensive. Furthermore, Profit against chemical costs (α) Chemical reduction proportion (β) and Profit sharing agreement between service provider and the farmer (γ) are the important determinants of the unit of payment. These determinants are not universal and are variable from one project to another depending on numerous domain specific factors