A multithreaded hybrid framework for mining frequent itemsets

Mining frequent itemsets is an area of data mining that has beguiled several researchers in recent years. Varied data structures such as Nodesets, DiffNodesets, NegNodesets, N-lists, and Diffsets are among a few that were employed to extract frequent items. However, most of these approaches fell short either in respect of run time or memory. Hybrid frameworks were formulated to repress these issues that encompass the deployment of two or more data structures to facilitate effective mining of frequent itemsets. Such an approach aims to exploit the advantages of either of the data structures while mitigating the problems of relying on either of them alone. However, limited efforts have been made to reinforce the efficiency of such frameworks. To address these issues this paper proposes a novel multithreaded hybrid framework comprising of NegNodesets and N-list structure that uses the multicore feature of today’s processors. While NegNodesets offer a concise representation of itemsets, N-lists rely on List intersection thereby speeding up the mining process. To optimize the extraction of frequent items a hash-based algorithm has been designed here to extract the resultant set of frequent items which further enhances the novelty of the framework

Flexible constrained sampling with guarantees for pattern mining

Pattern sampling has been proposed as a potential solution to the infamous pattern explosion. Instead of enumerating all patterns that satisfy the constraints, individual patterns are sampled proportional to a given quality measure. Several sampling algorithms have been proposed, but each of them has its limitations when it comes to 1) flexibility in terms of quality measures and constraints that can be used, and/or 2) guarantees with respect to sampling accuracy. We therefore present Flexics, the first flexible pattern sampler that supports a broad class of quality measures and constraints, while providing strong guarantees regarding sampling accuracy. To achieve this, we leverage the perspective on pattern mining as a constraint satisfaction problem and build upon the latest advances in sampling solutions in SAT as well as existing pattern mining algorithms. Furthermore, the proposed algorithm is applicable to a variety of pattern languages, which allows us to introduce and tackle the novel task of sampling sets of patterns. We introduce and empirically evaluate two variants of Flexics: 1) a generic variant that addresses the well-known itemset sampling task and the novel pattern set sampling task as well as a wide range of expressive constraints within these tasks, and 2) a specialized variant that exploits existing frequent itemset techniques to achieve substantial speed-ups. Experiments show that Flexics is both accurate and efficient, making it a useful tool for pattern-based data exploration.Comment: Accepted for publication in Data Mining & Knowledge Discovery journal (ECML/PKDD 2017 journal track

Improving Hypernymy Extraction with Distributional Semantic Classes

In this paper, we show how distributionally-induced semantic classes can be helpful for extracting hypernyms. We present methods for inducing sense-aware semantic classes using distributional semantics and using these induced semantic classes for filtering noisy hypernymy relations. Denoising of hypernyms is performed by labeling each semantic class with its hypernyms. On the one hand, this allows us to filter out wrong extractions using the global structure of distributionally similar senses. On the other hand, we infer missing hypernyms via label propagation to cluster terms. We conduct a large-scale crowdsourcing study showing that processing of automatically extracted hypernyms using our approach improves the quality of the hypernymy extraction in terms of both precision and recall. Furthermore, we show the utility of our method in the domain taxonomy induction task, achieving the state-of-the-art results on a SemEval'16 task on taxonomy induction.Comment: In Proceedings of the 11th Conference on Language Resources and Evaluation (LREC 2018). Miyazaki, Japa

Detecting Structure In Chaos: A Customer Process Analysis Method

Detecting typical patterns in customer processes is the precondition for gaining an understanding about customer issues and needs in the course of performing their processes. Such insights can be translated into customer-centric service offerings that provide added value by enabling customers to reach their process objectives more effectively and rapidly, and with less effort. However, customer processes performed in less restrictive environments are extremely heterogeneous, which makes them difficult to analyse. Current approaches deal with this issue by considering customer processes in large scope and low detail, or vice versa. However, both views are required to understand customer processes comprehensively. Therefore, we present a novel customer process analysis method capable of detecting the hidden activity-cluster structure of customer processes. Consequently, both the detailed level of process activities and the aggregated cluster level are available for customer process analysis, which increases the chances of detecting patterns in these heterogeneous processes. We apply the method to two datasets and evaluate the results’ validity and utility. Moreover, we demonstrate that the method outperforms alternative solution technologies. Finally, we provide new insights into customer process theory

CONSUMER CHARACTERISTICS INFLUENCING THE CONSUMPTION OF NUT-CONTAINING PRODUCTS

The study estimates the influence of consumer characteristics on the consumption of four nut-containing products, that is, the consumption of nuts as a snack, in salads, covered in chocolate, and in ice cream. Gender, age and education are among the characteristics that frequently influence nut consumption. Female, older, and non-white respondents consumed nuts as a snack more often than male, younger, and white consumers did. Chocolate-covered nut consumption was associated with higher income and rural consumers while nut-flavored ice cream was consumed more frequently by older rather than younger respondents and respondents from larger households.Consumer/Household Economics,

An evaluation of Digital Chisel 3.0 as a multimedia authoring tool in a year seven classroom

Most commercial interactive multimedia authoring packages are designed to be used by teachers and trainers to build commercial training or classroom teaching applications (Handler, Dana, Peters & Moor, 1995; Magel, 1997). The evolution of interactive multimedia technologies however, has made it possible for students to become actively involved in creating their own interactive multimedia projects, and in so doing, gain considerable learning benefit (Lehrer 1993). Facilitating this in the classroom and particularly at the Year Seven level, requires the use of a cost-effective, purpose-built authoring tool. Digital Chisel 3.0 (DC3), was developed by Pierian Spring Software (1997), as just such a product. This study was a summative product evaluation, utilising qualitative methodology that assessed the effectiveness of DC3, as a multimedia authoring tool for student use in a Year Seven classroom. Two adult expert reviewers and four Year Seven students assisted with the evaluation. The sources of evidence for this study included the use of participant observation, conversational and semi-structured interview, video recording, questionnaire and anecdotal field notes. The process of analysis was inductive, using the Analytic Framework suggested by Le Compte, Millroy & Preissle, (1992, pp. 763-766). Digital Chisel 3.0 was packaged with an easy to read printed manual and a useful audio/visual library on CD-ROM. With WYSIWYG display and drag-and-drop visual programming environments, the students found the component routines in DC3 relatively easy to learn. The use of the Microsoft style of interface and edit conventions allowed the previous learning of the students to be readily transferred to this product. The students also found constructing complex interactions in the Workbench relatively easy to master, as no scripting was required. DC3 was also customisable to three learning/school levels. Probably the most outstanding problem with this application was the amount of RAM it required to run efficiently. In it\u27s former configuration, it did not allow \u27room\u27 for multi-tasking and definitely did not run smoothly at the recommended 32 Megabytes of RAM. This both lowered the efficiency of operation, and severely challenged the motivation of all the users. The Table facility was almost totally unusable, as it failed to hold inserted elements and remained unstable through all attempts to use it. Although the intention for DC3 was to allow for cross-platform application, this function was not evident at the time it was evaluated. However, despite its shortcomings, Digital Chisel 3.0 proved to be well received by the students. They expressed enthusiasm for the extra freedom that this product\u27s features provided

Exploring Relations Between Motivation, Metacognition, and Academic Achievement Through Variable-Centered, Person-Centered and Learning Analytic Methodologies

The three studies that comprise this dissertation examine relations between student characteristics, motivations, metacognitive learning processes, and academic achievement. Methodologically, the dissertation demonstrated the potential of multiple types of approaches and data resource types. By employing multiple approaches including variable-centered, person-centered, and learning analytics, researchers can understand learning processes from various angles. In addition, through this triangulation by multiple types of methodological approaches, educational theories could be more thoroughly verified and supported by various empirical findings. Multiple types of data resources are related to analytical methods. The purpose of the first paper was to examine relations between achievement goals and metacognitive learning behaviors using a clustering analysis and visualization. A clustering analysis conducted with achievement goals produced three goal profiles; 1) mastery-approach, 2) performance-approach, and 3) performance-avoidance identified three goal profiles. The profiles include High Approach, High Mastery, and High Goal Endorsement groups. The finding demonstrated that students in the High Mastery group, who had greater use of the self-assessment tool, obtained higher final grades than other groups could be explained from the perspective of SRL. In addition, learners motivated by mastery approach goals engaged in the greater use of self-assessment quizzes. Students in the High Mastery group also used the tools earlier than other two groups for exam 2. As the most frequently used pattern, sequential pattern mining discovered the repeated use of self-assessment quizzes to monitor their learning. More students in the High Mastery group employ this pattern of metacognitive events than students in the High Performance and High-Goal endorsement groups, particularly during sessions in weeks before exams. A subsequent analysis revealed that for all exams, students who conducted a repeated behavior pattern indicative of metacognitive monitoring and control outperformed those who did not. From the research, it is confirmed that the person-centered analysis provided authentic and generalizable groups and afforded observation of the learning behaviors of learners with typical combinations of goals. In addition, sequential patterns provide instructor more interesting information on learning processes than the frequency of accesses. The purpose of the second research was to identify motivational profiles based on multiple types of motivations including self-efficacy, achievement goals, and expectancy-value from an integrative perspective. For this research, a LPA was conducted with ten types of motivational constructs and three kinds of metacognitive learning processes. The LPA identified four motivational profiles; 1) High Cost, 2) High Performance Goals, 3) High Goals and Values, and 4) Low Performance Goals, and three metacognitive profiles; 1) Infrequent metacognitive processing. 2) Checking performance and planning, and 3) Self-assessment. Student demographic information significantly influenced the membership of motivational profiles. Older students tend to have higher self-efficacy, mastery-approach, and values, but low cost than younger ones. In addition, compared to Caucasian and Asian students, underrepresented students tend to be more motivated by higher goals and values than high cost or high performance goals. Lastly, female students are more likely to be members of High performance goals and High goals and values than High cost oriented and Low performance goals and cost than males. In terms of the relations profiles with academic achievement, Low Performance Goals group showed the best performance. Among metacognitive profile groups, students in Checking performance and planning, and Self-assessment demonstrated similar academic performance. The investigation of relations between two profile groups demonstrated that students in the High cost group are more likely to be a member of self-assessment group than checking performance and planning as well as of a member of an infrequent metacognitive process than checking performance and planning. In addition, students in high performance and goals and high goals and values groups relative to the low performance goals group more likely to be a member of the infrequent metacognitive process than checking performance and planning. The findings of this research provide authentic motivation status and metacognition learning process as well as their relations. Addition, this research figured out specific motivational profiles through the multiple types of motivations from the integrative perspective. Therefore, instructors can provide more effective and specific interventions to students who have difficulty utilizing metacognitive learning processes, considering motivational status based on multiple motivations. In addition, instructors can understand motivational profiles by demographics so at the beginning of the semester in which the information on students is not enough to identify students learning processes, they intervene students based on demographic information. The purpose of the third paper was to consider the relative importance of capturing demographic, motivational and metacognitive processes as potential predictors of learning outcomes, and appraises them alongside both traditional prediction modeling approaches in higher education, and emergent methods, sequence pattern mining, arising from the field of educational data mining. The sequence pattern mining discovered the repeated use of self-assessment quizzes in Biology and repeated use of planning contents in Math. A regression model with combined resource types demonstrated the improved predictive power than models with individual resource types. Also, theory-aligned behaviors designed based on metacognitive learning processes better improved the accuracy of the model than non-theory-aligned behaviors automatically provided by the system. Lastly, when applying the same prediction model, the model better explained the variance of academic achievement in Biology in which metacognitive supporting tools designed based on an educational theory than that in Math that has few theory-aligned behavior variables. Therefore, this study emphasizes the importance of existing ambient data from university systems. Also, log data generated by systems such as LMS allows researchers to examine the same data in different ways with no need for additional data collection. Lastly, educational theory and contexts should be taken into consideration in designing courses and developing the prediction models. Therefore, instructors and researchers, in designing courses, the consideration of educational theories and contexts is the essential process. This dissertation provides insight regarding authentic relations between motivation, metacognition, and academic achievement. Specifically, instructors can understand how multiple types of motivations work together, and the motivational profiles influence metacognitive learning strategies. In courses, by examining motivational profiles, instructors can provide more effective intervention with which students change their resolve their weak learning easier. Practically, by investigating each type of predictor from data resources including demographic, motivation, and behavioral variables, findings from this dissertation can enable researchers to prioritize development of prediction models to identify students who are more likely to experience failure in courses. Additionally, instructors can figure out the importance of interpreting variables through educational theories and in context through the comparison of courses with differing instructional designs. Further, by appraising these results in light of theory, instructors can take action to improve student’s learning outcomes by adjusting the design of their courses