Open University Learning Analytics dataset

Learning Analytics focuses on the collection and analysis of learners’ data to improve their learning experience by providing informed guidance and to optimise learning materials. To support the research in this area we have developed a dataset, containing data from courses presented at the Open University (OU). What makes the dataset unique is the fact that it contains demographic data together with aggregated clickstream data of students’ interactions in the Virtual Learning Environment (VLE). This enables the analysis of student behaviour, represented by their actions. The dataset contains the information about 22 courses, 32,593 students, their assessment results, and logs of their interactions with the VLE represented by daily summaries of student clicks (10,655,280 entries). The dataset is freely available at https://analyse.kmi.open.ac.uk/open_dataset under a CC-BY 4.0 license

Preserving prosumer privacy in a district level smart grid

This study presents the anonymization of consumer data in a district-level smart grid using the k-anonymity approach. The data utilized in this study covers the demographic information and associated energy consumption of consumers. The anonymization process is implemented at the prosumer level, considering their importance in sharing flexibility and distributed generation at the low voltage grid, and the fact that they need to interact with each other and the grid while keeping their data private. The proposed approach is tested under three anonymization scenarios: prosecutor, journalist, and marketer. The smart grid data are investigated mostly under the prosecutor scenario with three risk levels: lowest, medium and highest. The results of the k-anonymity approach are compared to k-map and k-map + k-anonymity. No difference has been found between the three investigated approaches for the selected data set. Since, the aim of the k-anonymity is to not transform the information about any individual record among those k-1 individuals, the recorded type and the number of attributes play a key role in the anonymization process. One of the risks is the using continuous attributes in the anonymization process which may cause the information lose in the anonymization process such as near real-time energy consumptions. Hence we have focused on to anonymization of the consumers' demographic information, rather than their energy consumption

Feedback-based integration of the whole process of data anonymization in a graphical interface

The interactive, web-based point-and-click application presented in this article, allows anonymizing data without any knowledge in a programming language. Anonymization in data mining, but creating safe, anonymized data is by no means a trivial task. Both the methodological issues as well as know-how from subject matter specialists should be taken into account when anonymizing data. Even though specialized software such as sdcMicro exists, it is often difficult for nonexperts in a particular software and without programming skills to actually anonymize datasets without an appropriate app. The presented app is not restricted to apply disclosure limitation techniques but rather facilitates the entire anonymization process. This interface allows uploading data to the system, modifying them and to create an object defining the disclosure scenario. Once such a statistical disclosure control (SDC) problem has been defined, users can apply anonymization techniques to this object and get instant feedback on the impact on risk and data utility after SDC methods have been applied. Additional features, such as an Undo Button, the possibility to export the anonymized dataset or the required code for reproducibility reasons, as well its interactive features, make it convenient both for experts and nonexperts in R – the free software environment for statistical computing and graphics – to protect a dataset using this app

Portinari: A Data Exploration Tool to Personalize Cervical Cancer Screening

Socio-technical systems play an important role in public health screening programs to prevent cancer. Cervical cancer incidence has significantly decreased in countries that developed systems for organized screening engaging medical practitioners, laboratories and patients. The system automatically identifies individuals at risk of developing the disease and invites them for a screening exam or a follow-up exam conducted by medical professionals. A triage algorithm in the system aims to reduce unnecessary screening exams for individuals at low-risk while detecting and treating individuals at high-risk. Despite the general success of screening, the triage algorithm is a one-size-fits all approach that is not personalized to a patient. This can easily be observed in historical data from screening exams. Often patients rely on personal factors to determine that they are either at high risk or not at risk at all and take action at their own discretion. Can exploring patient trajectories help hypothesize personal factors leading to their decisions? We present Portinari, a data exploration tool to query and visualize future trajectories of patients who have undergone a specific sequence of screening exams. The web-based tool contains (a) a visual query interface (b) a backend graph database of events in patients' lives (c) trajectory visualization using sankey diagrams. We use Portinari to explore diverse trajectories of patients following the Norwegian triage algorithm. The trajectories demonstrated variable degrees of adherence to the triage algorithm and allowed epidemiologists to hypothesize about the possible causes.Comment: Conference paper published at ICSE 2017 Buenos Aires, at the Software Engineering in Society Track. 10 pages, 5 figure

Anonimização de Dados em Educação

Interest in data privacy is not only growing, but the quantity of data collected is also increasing. This data, which is collected and stored electronically, contains information related with all aspects of our lives, frequently containing sensitive information, such as financial records, activity in social networks, location traces collected by our mobile phones and even medical records. Consequently, it becomes paramount to assure the best protection for this data, so that no harm is done to individuals even if the data is to become publicly available. To achieve it, it is necessary to avoid the linkage between records in a dataset and a real world individual. Despite some attributes, such as gender and age, though alone they can not identify a corresponding individual, their combination with other datasets can lead to the existence of unique records in the dataset and a consequent linkage to a real world individual. Therefore, with data anonymization, it is possible to assure, with various degrees of protection, that said linkage is avoided the best we can. However, this process can have a decline in data utility as consequence. In this work, we explore the terminology and some of the techniques that can be used during the process of data anonymization. Moreover, we show the effects of said techniques on information loss, data utility and re-identification risk, when applied to a dataset with personal information collected from college graduated students. Finally, and once the results are presented, we perform an analysis and comparative discussion of the obtained results.Hoje em dia é possível observar que tanto a preocupação com a privacidade dos dados pessoais como a quantidade de dados recolhidos estão a aumentar. Estes dados, recolhidos e armazenados eletronicamente, contêm informação relacionada com todos os aspetos das nossas vidas, informação essa muitas vezes sensível, tal como registos financeiros, atividade em redes sociais, rastreamento de dispositivos móveis e até registos médicos. Consequentemente, torna-se vital assegurar a proteção destes dados para que, mesmo se tornados públicos, não causem danos pessoais aos indivíduos envolvidos. Para isso, é necessário evitar que registos nos dados sejam associados a indivíduos reais. Apesar de atributos, como o género e a idade, singularmente não conseguirem identificar o individuo correspondente, a sua combinação com outros conjuntos de dados, pode levar à existência de um registo único no conjunto de dados e consequente associação a um individuo. Com a anonimização dos dados, é possível assegurar, com variados graus de proteção, que essa associação a um individuo real seja evitada ao máximo. Contudo, este processo pode ter como consequência uma diminuição na utilidade dos dados. Com este trabalho, exploramos a terminologia e algumas das técnicas que podem ser utilizadas no processo de anonimização de dados. Mostramos também os efeitos dessas várias técnicas tanto na perda de informação e utilidade dos dados, como no risco de re-identificação associado, quando aplicadas a um conjunto de dados com informação pessoal recolhida a alunos que conluíram o ensino superior. No final, e uma vez feita a apresentação dos resultados, é feita uma análise e discussão comparativa dos resultados obtidos