Modeling the Dynamics of Consumer Behavior from Massive Interaction Data

Recent technological innovations (e.g. e-commerce platforms, automated retail stores) have enabled dramatic changes in people's shopping experiences, as well as the accessibility to incredible volumes of consumer-product interaction data. As a result, machine learning (ML) systems can be widely developed to help people navigate relevant information and make decisions. Traditional ML systems have achieved great success on various well-defined problems such as speech recognition and facial recognition. Unlike these tasks where datasets and objectives are clearly benchmarked, modeling consumer behavior can be rather complicated; for example, consumer activities can be affected by real-time shopping contexts, collected interaction data can be noisy and biased, interests from multiple parties (both consumers and producers) can be involved in the predictive objectives.The primary goal of this dissertation is to address the obstacles in modeling consumer activities through computational approaches, but with careful considerations from economic and societal perspectives. Intellectually, such models help us to understand the forces that guide consumer behavior. Methodologically, I build algorithms capable of processing massive interaction datasets by connecting well-developed ML techniques and well-established economic theories. Practically, my work has applications ranging from recommender systems, e-commerce and business intelligence

Salience and Market-aware Skill Extraction for Job Targeting

At LinkedIn, we want to create economic opportunity for everyone in the global workforce. To make this happen, LinkedIn offers a reactive Job Search system, and a proactive Jobs You May Be Interested In (JYMBII) system to match the best candidates with their dream jobs. One of the most challenging tasks for developing these systems is to properly extract important skill entities from job postings and then target members with matched attributes. In this work, we show that the commonly used text-based \emph{salience and market-agnostic} skill extraction approach is sub-optimal because it only considers skill mention and ignores the salient level of a skill and its market dynamics, i.e., the market supply and demand influence on the importance of skills. To address the above drawbacks, we present \model, our deployed \emph{salience and market-aware} skill extraction system. The proposed \model ~shows promising results in improving the online performance of job recommendation (JYMBII) ($+1.92\%$ job apply) and skill suggestions for job posters ($-37\%$ suggestion rejection rate). Lastly, we present case studies to show interesting insights that contrast traditional skill recognition method and the proposed \model~from occupation, industry, country, and individual skill levels. Based on the above promising results, we deployed the \model ~online to extract job targeting skills for all $20$M job postings served at LinkedIn.Comment: 9 pages, to appear in KDD202

La tecnología central detrás y más allá de ChatGPT: Una revisión exhaustiva de los modelos de lenguaje en la investigación educativa

ChatGPT has garnered significant attention within the education industry. Given the core technology behind ChatGPT is language model, this study aims to critically review related publications and suggest future direction of language model in educational research. We aim to address three questions: i) what is the core technology behind ChatGPT, ii) what is the state of knowledge of related research and iii) the potential research direction. A critical review of related publications was conducted in order to evaluate the current state of knowledge of language model in educational research. In addition, we further suggest a purpose oriented guiding framework for future research of language model in education. Our study promptly responded to the concerns raised by ChatGPT from the education industry and offers the industry with a comprehensive and systematic overview of related technologies. We believe this is the first time that a study has been conducted to systematically review the state of knowledge of language model in educational research. ChatGPT ha atraído una gran atención en el sector educativo. Dado que la tecnología central detrás de ChatGPT es el modelo de lenguaje, este estudio tiene como objetivo revisar críticamente publicaciones relacionadas y sugerir la dirección futura del modelo de lenguaje en la investigación educativa. Nuestro objetivo es abordar tres preguntas: i) cuál es la tecnología central detrás de ChatGPT, ii) cuál es el nivel de conocimiento de la investigación relacionada y iii) la dirección del potencial de investigación. Se llevó a cabo una revisión crítica de publicaciones relacionadas con el fin de evaluar el estado actual del conocimiento del modelo lingüístico en la investigación educativa. Además, sugerimos un marco rector para futuras investigaciones sobre modelos lingüísticos en educación. Nuestro estudio respondió rápidamente a las preocupaciones planteadas por el uso de ChatGPT en la industria educativa y proporciona a la industria una descripción general completa y sistemática de las tecnologías relacionadas. Creemos que esta es la primera vez que se realiza un estudio para revisar sistemáticamente el nivel de conocimiento del modelo lingüístico en la investigación educativa

Personalization, Cognition, and Gamification-based Programming Language Learning: A State-of-the-Art Systematic Literature Review

Programming courses in computing science are important because they are often the first introduction to computer programming for many students. Many university students are overwhelmed with the information they must learn for an introductory course. The current teacher-lecturer model of learning commonly employed in university lecture halls often results in a lack of motivation and participation in learning. Personalized gamification is a pedagogical approach that combines gamification and personalized learning to motivate and engage students while addressing individual differences in learning. This approach integrates gamification and personalized learning strategies to inspire and involve students while addressing their unique learning needs and differences. A comprehensive literature search was conducted by including 81 studies that were analyzed based on their research design, intervention, outcome measures, and quality assessment. The findings suggest that personalized gamification can enhance student cognition in programming courses by improving motivation, engagement, and learning outcomes. However, the effectiveness of personalized gamification varies depending on various factors, such as the type of gamification elements used, the degree of personalization, and the characteristics of the learners. This paper provides insights into designing and implementing effective personalized gamification interventions in programming courses. The findings could inform educational practitioners and researchers in programming education about the potential benefits of personalized gamification and its implications for educational practice

X-Eval: Generalizable Multi-aspect Text Evaluation via Augmented Instruction Tuning with Auxiliary Evaluation Aspects

Natural Language Generation (NLG) typically involves evaluating the generated text in various aspects (e.g., consistency and naturalness) to obtain a comprehensive assessment. However, multi-aspect evaluation remains challenging as it may require the evaluator to generalize to any given evaluation aspect even if it's absent during training. In this paper, we introduce X-Eval, a two-stage instruction tuning framework to evaluate the text in both seen and unseen aspects customized by end users. X-Eval consists of two learning stages: the vanilla instruction tuning stage that improves the model's ability to follow evaluation instructions, and an enhanced instruction tuning stage that exploits the connections between fine-grained evaluation aspects to better assess text quality. To support the training of X-Eval, we collect AspectInstruct, the first instruction tuning dataset tailored for multi-aspect NLG evaluation spanning 27 diverse evaluation aspects with 65 tasks. To enhance task diversity, we devise an augmentation strategy that converts human rating annotations into diverse forms of NLG evaluation tasks, including scoring, comparison, ranking, and Boolean question answering. Extensive experiments across three essential categories of NLG tasks: dialogue generation, summarization, and data-to-text coupled with 21 aspects in meta-evaluation, demonstrate that our X-Eval enables even a lightweight language model to achieve a comparable if not higher correlation with human judgments compared to the state-of-the-art NLG evaluators, such as GPT-4.Comment: 17 pages, 5 figures, 14 table

Complex Temporal Question Answering on Knowledge Graphs

Question answering over knowledge graphs (KG-QA) is a vital topic in IR. Questions with temporal intent are a special class of practical importance, but have not received much attention in research. This work presents EXAQT, the first end-to-end system for answering complex temporal questions that have multiple entities and predicates, and associated temporal conditions. EXAQT answers natural language questions over KGs in two stages, one geared towards high recall, the other towards precision at top ranks. The first step computes question-relevant compact subgraphs within the KG, and judiciously enhances them with pertinent temporal facts, using Group Steiner Trees and fine-tuned BERT models. The second step constructs relational graph convolutional networks (R-GCNs) from the first step's output, and enhances the R-GCNs with time-aware entity embeddings and attention over temporal relations. We evaluate EXAQT on TimeQuestions, a large dataset of 16k temporal questions we compiled from a variety of general purpose KG-QA benchmarks. Results show that EXAQT outperforms three state-of-the-art systems for answering complex questions over KGs, thereby justifying specialized treatment of temporal QA