User k-anonymity for privacy preserving data mining of query logs

The anonymization of query logs is an important process that needs to be performed prior to the publication of such sensitive data. This ensures the anonymity of the users in the logs, a problem that has been already found in released logs from well known companies. This paper presents the anonymization of query logs using microaggregation. Our proposal ensures the k-anonymity of the users in the query log, while preserving its utility. We provide the evaluation of our proposal in real query logs, showing the privacy and utility achieved, as well as providing estimations for the use of such data in data mining processes based on clustering.     

An assessment of the sources of the reversal error through classic and new variables

We present two empirical studies with 241 and 211 pre-service teachers that evaluate the explanatory power of word order matching and static comparison as models for the reversal error. We used tasks consisting of generating an algebraic equation representing a comparison given in a verbal statement. We introduce the types of magnitude involved in the statement as variables of analysis, something that was not previously tackled in previous works. Our results show that there are no statistical differences in the production of reversal errors depending on the information included in the name used to designate the variable, and that there are statistical differences depending on the syntactic configuration as well as the type of magnitude involved in the statement. The interpretation of these results indicates that both word order matching and static comparison have some potential as explanatory models for the reversal error, and that neither one of them, alone, is enough to completely explain the phenomenon.     

Geographical mobility and children’s non-completion of upper secondary education in Finland and Germany: Do parental resources matter?

It is often assumed that families migrate to improve their economic and social prospects, and that these additional resources can benefit the whole family. However, existing research suggests that many children who have experienced (internal) migration underperform compared to their non-migrating peers in terms of different socioeconomic outcomes. In this article, we study the effects of geographical mobility on children’s non-completion of upper secondary education in Finland and Germany using Finnish register data and the German National Educational Panel Study. Our findings indicate that moving during childhood is associated with the risk of not attaining any secondary degree in both countries. In Finland, this is mostly explained by negative selection into moving (i.e. those who move are more likely to be disadvantaged). In Germany, however, an independent association between moving and educational attainment remains after taking into account various reasons why families move. Furthermore, for both Germany and Finland, any labour force status or earning gains parents make after a move do not seem to compensate for the negative influence of internal migration on children’s educational dropout. Overall, we conclude that geographically mobile children may be a vulnerable subgroup in the inter-generational transmission of inequality, therefore schools have an important role to play in integrating internal migrants—as well as international migrants—into the social networks of the schools they arrive in.     

Intensive scaffolding in an intelligent tutoring system for the learning of algebraic word problem solving

The term intensive scaffolding refers to any set of conceptual scaffolding strategies that always allow the user to find the solution to a problem. Despite the many benefits of scaffolding, some negative effects have also been reported. These are mainly related to the possibility that a student solves the problems without actually engaging in their content. In this paper, we have used an intelligent tutoring system (ITS) to analyze the effect that intensive scaffolding has on the learning of algebraic word problem solving (AWPS). Two different versions of the ITS, which differ in the amount of scaffolding that they provide, have been created. These two versions were used by two groups of students in Secondary Education, in a quasi‐experimental study. The comparison of pre‐ and posttest scores shows a significant increase of the competence in AWPS in the group that used the ITS with intensive scaffolding.     

Incorporating oximeter analyses to investigate synchronies in heart rate while teaching and learning about race

In this paper, we look closely at two events selected through event-oriented inquiry that were part of a classroom presentation on race. The first event was a provocative discussion about Mark Twain’s (Pudd’nhead Wilson, Harper, New York, 1899) and passing for being White. The other was a discussion on the use of the N-word. Grounded in authentic inquiry, we use ethnographic narrative, cogenerative dialogues, and video and oximeter data analyses as part of a multi-ontological approach for studying emotions. Statistical analysis of oximeter data shows statistically significant heart rate synchrony among two of the coteachers during their presentations, providing evidence of emotional synchrony, resonance, and social and emotional contagion.     

Mindfulness and discussing “thorny” issues in the classroom

Being in the moment, showing compassion, being non-judgmental, acknowledging deep emotional challenges without getting stuck: these are mindfulness characteristics important to us as teachers, yet not often included in teacher preparation. These concerns become magnified when we focus on difficult knowledge and thorny issues, like topics related to gender and race. Using a sociocultural framework, we address how mindfulness, heuristics, and other contemplative practices can be adopted to create safe, supporting, and healing spaces for such complex, often emotionally painful discussions. Participant narratives are used extensively to provide a voice to those marginalized or hurt. Drawing from these narratives and their experience in discussing thorny issues, we put forth possible solutions and interventions that can create spaces that encourage and support critical discourse through mindful practices. The development of a heuristic for discussing thorny issues whose characteristics can be adopted by interested teachers and educators to help frame and mediate this type of difficult discussion is an outcome of this research.     

Indexical Expressions in Word Problems and their Influence on Multiple Referents of the Unknown

When translating word problems into equations, a common error consists of using the same letter to refer to two different quantities. This error, called multiple referents for the unknown, can be connected to the existence of deictic or indexical expressions within the problem statement. This paper aims to analyse the influence of indexical expressions on the incidence of the multiple referents for the unknown error. Results from a quantitative study with 117 Spanish secondary students show a significantly higher number of such type of error when the problem statement contains indexical expressions. The analysis of students’ performances in subsequent interviews indicates that this error may be due to the fragmented reading of statements.     

Building personalised homework from a learning analytics based formative assessment: Effect on fifth-grade students' understanding of fractions

This study analyses the potential of a learning analytics (LA) based formative assessment to construct personalised teaching sequences in Mathematics for 5th-grade primary school students. A total of 127 students from Spanish public schools participated in the study. The quasi-experimental study was conducted over the course of six sessions, in which both control and experimental groups participated in a teaching sequence based on mathematical problems. In each session, both groups used audience response systems to record their responses to mathematical tasks about fractions. After each session, students from the control group were given generic homework on fractions—the same activities for all the participants—while students from the experimental group were given a personalised set of activities. The provision of personalised homework was based on the students' errors detected from the use of the LA-based formative assessment. After the intervention, the results indicate a higher student level of understanding of the concept of fractions in the experimental group compared to the control group. Related to motivational dimensions, results indicated that instruction using audience response systems has a positive effect compared to regular mathematics classes.

Practitioner notes

What is already known about this topic

• Developing an understanding of fractions is one of the most challenging concepts in elementary mathematics and a solid predictor of future achievements in mathematics.
• Learning analytics (LA) has the potential to provide quality, functional data for assessing and supporting learners' difficulties.
• Audience response systems (ARS) are one of the most practical ways to collect data for LA in classroom environments.
• There is a scarcity of field research implementations on LA mediated by ARS in real contexts of elementary school classrooms.

What this paper adds

• Empirical evidence about how LA-based formative assessments can enable personalised homework to support student understanding of fractions.
• Personalised homework based on an LA-based formative assessment improves the students' comprehension of fractions.
• Using ARS for the teaching of fractions has a positive effect in terms of student motivation.

Implications for practice and/or policy

• Teachers should be given LA/ARS tools that allow them to quickly provide students with personalised mathematical instruction.
• Researchers should continue exploring these potentially beneficial educational implementations in other areas.