OpenRaiser/Intern-Atlas huggingface dataset:
Fast Learning of MNL Model from General Partial Rankings with Application to Network Formation Modeling
Authors: Jiaqi Ma, Xingjian Zhang, Qiaozhu Mei
Venue: WSDM
Year: 2022

Multinomial Logit (MNL) is one of the most popular discrete choice models and has been widely used to model ranking data. However, there is a long-standing technical challenge of learning MNL from many real-world ranking data: exact calculation of the MNL likelihood of partial rankings is generally intractable. In this work, we develop a scalable method for approximating the MNL likelihood of general partial rankings in polynomial time complexity. We also extend the proposed method to learn mixture of MNL. We demonstrate that the proposed methods are particularly helpful for applications to choice-based network formation modeling, where the formation of new edges in a network is viewed as individuals making choices of their friends over a candidate set. The problem of learning mixture of MNL models from partial rankings naturally arises in such applications. And the proposed methods can be used to learn MNL models from network data without the strong assumption that temporal orders of all the edge formation are available. We conduct experiments on both synthetic and real-world network data to demonstrate that the proposed methods achieve more accurate parameter estimation and better fitness of data compared to conventional methods.
Sentiment Analysis of Fashion Related Posts in Social Media
Authors: Yifei Yuan, Wai Lam
Venue: WSDM
Year: 2022

The role of social media in fashion industry has been blooming as the years have continued on. In this work, we investigate sentiment analysis for fashion related posts in social media platforms. There are two main challenges of this task. On the first place, information of different modalities must be jointly considered to make the final predictions. On the second place, some unique fashion related attributes should be taken into account. While most existing works focus on traditional multimodal sentiment analysis, they always fail to exploit the fashion related attributes in this task. We propose a novel framework that jointly leverages the image vision, post text, as well as fashion attribute modality to determine the sentiment category. One characteristic of our model is that it extracts fashion attributes and integrates them with the image vision information for effective representation. Furthermore, it exploits the mutual relationship between the fashion attributes and the post texts via a mutual attention mechanism. Since there is no existing dataset for this task, we prepare a large-scale sentiment analysis dataset of over 12k fashion related social media posts. Extensive experiments are conducted to demonstrate the effectiveness of our model.
MotifClass: Weakly Supervised Text Classification with Higher-order Metadata Information
Authors: Yu Zhang, Shweta Garg, Yu Meng, Xiusi Chen, Jiawei Han
Venue: WSDM
Year: 2022

We study the problem of weakly supervised text classification, which aims to classify text documents into a set of pre-defined categories with category surface names only and without any annotated training document provided. Most existing classifiers leverage textual information in each document. However, in many domains, documents are accompanied by various types of metadata (e.g., authors, venue, and year of a research paper). These metadata and their combinations may serve as strong category indicators in addition to textual contents. In this paper, we explore the potential of using metadata to help weakly supervised text classification. To be specific, we model the relationships between documents and metadata via a heterogeneous information network. To effectively capture higher-order structures in the network, we use motifs to describe metadata combinations. We propose a novel framework, named MotifClass , which (1) selects category-indicative motif instances, (2) retrieves and generates pseudo-labeled training samples based on category names and indicative motif instances, and (3) trains a text classifier using the pseudo training data. Extensive experiments on real-world datasets demonstrate the superior performance of MotifClass to existing weakly supervised text classification approaches. Further analysis shows the benefit of considering higher-order metadata information in our framework.
Ethical Challenges in AI
Authors: Ricardo Baeza-Yates
Venue: WSDM
Year: 2022

In the first part we address four current specific challenges through examples: (1) discrimination (e.g., facial recognition, justice, sharing economy, language models); (2) stupid models (e.g., lack of semantic and context understanding); (3) physiognomy (e.g., facial bio-metrics based predictions); and (4) indiscriminate use of computing resources (e.g., large language models). These examples do have a personal bias but set the context for the second part where we address four generic challenges: (1) too many principles, (2) cultural differences; (3) regulation and (4) our cognitive biases. We finish discussing what we can do to address these challenges in the near future.
Harvesting More Answer Spans from Paragraph beyond Annotation
Authors: Qiaoben Bao, Jiangjie Chen, Linfang Liu, Jingping Liu, Jiaqing Liang, Yanghua Xiao
Venue: WSDM
Year: 2022

AutomaticA nswer spanE xtraction (AE) focuses on identifying key information from paragraphs that can be asked. It has been used to facilitate downstream question generation tasks or data augmentation for question answering. Current work of AE heavily relies on the annotated answer spans fromM achineR eadingC omprehension (MRC) datasets. However, these methods suffer from the partial annotation problem due to the annotation protocols of MRC tasks. To tackle this problem, we propose \mymethod, a S tructured Co ntext graph network with P ositive -unlabeled learning. \mymethod first represents the paragraph by constructing a graph with both syntactic and semantic edges, then adopts a unified pointer network for answer span identification. \mymethod narrows the discrenpency between AE and MRC by formulating AE as aP ositive-\textitu nlabeled (PU) learning problem, thus recovering more answer spans from paragraphs. To evaluate newly extracted spans without annotation, we also present an automatic metric from the perspective of question answering and text summarization, which correlates well with human judgments. Comprehensive experiments on both AE and downstream tasks demonstrate the effectiveness of our proposed framework. Our code is available at \urlhttps://github.com/iambabao/SCOPE.
Sampling Multiple Nodes in Large Networks: Beyond Random Walks
Authors: Omri Ben-Eliezer, Talya Eden, Joel Oren, Dimitris Fotakis
Venue: WSDM
Year: 2022

Sampling random nodes is a fundamental algorithmic primitive in the analysis of massive networks, with many modern graph mining algorithms critically relying on it. We consider the task of generating a large collection of random nodes in the network assuming limited query access (where querying a node reveals its set of neighbors). In current approaches, based on long random walks, the number of queries per sample scales linearly with the mixing time of the network, which can be prohibitive for large real-world networks. We propose a new method for sampling multiple nodes that bypasses the dependence in the mixing time by explicitly searching for less accessible components in the network. We test our approach on a variety of real-world and synthetic networks with up to tens of millions of nodes, demonstrating a query complexity improvement of up to x20 compared to the state of the art.
Search and Discovery in Personal Email Collections
Authors: Michael Bendersky, Xuanhui Wang, Marc Najork, Donald Metzler
Venue: WSDM
Year: 2022

Email has been an essential communication medium for many years. As a result, the information accumulated in our mailboxes has become valuable for all of our personal and professional activities. For years, researchers have developed interfaces, models, and algorithms to facilitate email search, discovery, and organization. This tutorial brings together these diverse research directions and provides both a historical background, as well as a high-level overview of the recent advances in the field. In particular, we lay out all of the components needed in the design of email search engines, including user interfaces, indexing, document and query understanding, retrieval, ranking, evaluation, and data privacy. The tutorial also goes beyond search, presenting recent work on intelligent task assistance in email and a number of interesting future directions.
'It's on the tip of my tongue': A new Dataset for Known-Item Retrieval
Authors: Samarth Bhargav, Georgios Sidiropoulos, Evangelos Kanoulas
Venue: WSDM
Year: 2022

The tip of the tongue known-item retrieval (TOT-KIR) task involves the 'one-off' retrieval of an item for which a user cannot recall a precise identifier. The emergence of several online communities where users pose known-item queries to other users indicates the inability of existing search systems to answer such queries. Research in this domain is hampered by the lack of large, open or realistic datasets. Prior datasets relied on either annotation by crowd workers, which can be expensive and time-consuming, or generating synthetic queries, which can be unrealistic. Additionally, small datasets make the application of modern (neural) retrieval methods unviable, since they require a large number of data-points. In this paper, we collect the largest dataset yet with 15K query-item pairs in two domains, namely, Movies and Books, from an online community using heuristics, rendering expensive annotation unnecessary while ensuring that queries are realistic. We show that our data collection method is accurate by conducting a data study. We further demonstrate that methods like BM25 fall short of answering such queries, corroborating prior research. The size of the dataset makes neural methods feasible, which we show outperforms lexical baselines, indicating that neural/dense retrieval is superior for the TOT-KIR task.
CAN: Feature Co-Action Network for Click-Through Rate Prediction
Authors: Weijie Bian, Kailun Wu, Lejian Ren, Qi Pi, Yujing Zhang, Can Xiao, Xiang-Rong Sheng, Yong-Nan Zhu, Zhangming Chan, Na Mou, Xinchen Luo, Shiming Xiang, Guorui Zhou, Xiaoqiang Zhu, Hongbo Deng
Venue: WSDM
Year: 2022

Feature interaction has been recognized as an important problem in machine learning, which is also very essential for click-through rate (CTR) prediction tasks. In recent years, Deep Neural Networks (DNNs) can automatically learn implicit nonlinear interactions from original sparse features, and therefore have been widely used in industrial CTR prediction tasks. However, the implicit feature interactions learned in DNNs cannot fully retain the complete representation capacity of the original and empirical feature interactions (e.g., cartesian product) without loss. For example, a simple attempt to learn the combination of feature A and feature B < A, B > as the explicit cartesian product representation of new features can outperform previous implicit feature interaction models including factorization machine (FM)-based models and their variations. This indicates there is still a big gap between explicit and implicit feature interaction models. However, to learn all the explicit feature interaction (cartesian product) representations requires a very large sample size along with N times of original parameter space (where N is quite large in most industrial applications). In this paper, we propose a Co-Action Network (CAN) to approximate the explicit pairwise feature interactions without introducing too many additional parameters. More specifically, giving feature A and its associated feature B, their feature interaction is modeled by learning two sets of parameters: 1) the embedding of feature A, and 2) a Multi-Layer Perceptron (MLP) to represent feature B. The approximated feature interaction can be obtained by passing the embedding of feature A through the MLP network of feature B. We refer to such pairwise feature interaction as feature co-action, and such a Co-Action Network unit can provide a very powerful capacity to fitting complex feature interactions. In addition, FM can be viewed as a special case of the CAN unit when the MLP is a single layer with only one output. Experimental results on public and industrial datasets show that CAN outperforms state-of-the-art CTR models and the cartesian product method. Moreover, CAN has been deployed in the display advertisement system in Alibaba, obtaining 12% improvement on CTR and 8% on Revenue Per Mille (RPM), which is a great improvement to the business. The code for experiments in this paper is open-sourced\footnotehttps://github.com/CAN-Paper/Co-Action-Network.
Quality Assurance of a German COVID-19 Question Answering Systems using Component-based Microbenchmarking
Authors: Andreas Both, Paul Heinze, Aleksandr Perevalov, Johannes Richard Bartsch, Rostislav Iudin, Johannes Rudolf Herkner, Tim Schrader, Jonas Wunsch, René Gürth, Ann Kristin Falkenhain
Venue: WSDM
Year: 2022

Question Answering (QA) has become an often used method to retrieve data as part of chatbots and other natural-language user interfaces. In particular, QA systems of official institutions have high expectations regarding the answers computed by the system, as the provided information might be critical. In this demonstration, we use the official COVID-19 QA system that was developed together with the German Federal government to provide German citizens access to data regarding incident values, number of deaths, etc. To ensure high quality, a component-based approach was used that enables exchanging data between QA components using RDF and validating the functionality of the QA system using SPARQL. Here, we will demonstrate how our solution enables developers of QA systems to use a descriptive approach to validate the quality of their implementation before the system's deployment and also within a live environment.
iLFQA: A Platform for Efficient and Accurate Long-Form Question Answering
Authors: Rhys Butler, Vishnu Dutt Duggirala, Farnoush Banaei Kashani
Venue: WSDM
Year: 2022

We present an efficient and accurate long-form question-answering platform, dubbed iLFQA (i.e., short for intelligent Long-Form Question Answering). The purpose of iLFQA is to function as a platform which accepts unscripted questions and efficiently produces semantically meaningful, explanatory, and accurate long-form responses. iLFQA consists of a number of modules for zero-shot classification, text retrieval, and text generation to generate answers to questions based on an open-domain knowledge base. iLFQA is unique in the question answering space because it is an example of a deployable and efficient long-form question answering system. Question answering systems exist in many forms, but long-form question answering remains relatively unexplored, and to the best of our knowledge none of the existing long-form question answering systems are shown to be sufficiently efficient to be deployable. We have made the source code and implementation details of iLFQA available for the benefit of researchers and practitioners in this field. With this demonstration, we present iLFQA as an open-domain, deployable, and accurate open-source long-form question answering platform.
Graph Collaborative Reasoning
Authors: Hanxiong Chen, Yunqi Li, Shaoyun Shi, Shuchang Liu, He Zhu, Yongfeng Zhang
Venue: WSDM
Year: 2022

Graphs can represent relational information among entities and graph structures are widely used in many intelligent tasks such as search, recommendation, and question answering. However, most of the graph-structured data in practice suffer from incompleteness, and thus link prediction becomes an important research problem. Though many models are proposed for link prediction, the following two problems are still less explored: (1) Most methods model each link independently without making use of the rich information from relevant links, and (2) existing models are mostly designed based on associative learning and do not take reasoning into consideration. With these concerns, in this paper, we propose Graph Collaborative Reasoning (GCR), which can use the neighbor link information for relational reasoning on graphs from logical reasoning perspectives. We provide a simple approach to translate a graph structure into logical expressions so that the link prediction task can be converted into a neural logic reasoning problem. We apply logical constrained neural modules to build the network architecture according to the logical expression and use backpropagation to efficiently learn the model parameters, which bridges differentiable learning and symbolic reasoning in a unified architecture. To show the effectiveness of our work, we conduct experiments on graph-related tasks such as link prediction and recommendation based on commonly used benchmark datasets, and our graph collaborative reasoning approach achieves state-of-the-art performance.
Exploration in Recommender Systems
Authors: Minmin Chen
Venue: WSDM
Year: 2022

In the era of increasing choices, recommender systems are becoming indispensable in helping users navigate the million or billion pieces of content on recommendation platforms. Most of the recommender systems are powered by ML models trained on a large amount of user-item interaction data. Such a setup however induces a strong feedback loop that creates the rich gets richer phenomenon where head contents are getting more and more exposure while tail and fresh contents are not discovered. At the same time, it pigeonholes users to contents they are already familiar with. We believe exploration is key to break away from the feedback loop and to optimize long term user experience on recommendation platforms. The exploration-exploitation tradeoff, being the foundation of bandits and RL research, has been extensively studied in RL. While effective exploration is believed to positively influence the user experience on the platform, the exact value of exploration in recommender systems has not been well established. In this talk, we examine the roles of exploration in recommender systems in three facets: 1) system exploration to surface fresh/tail recommendations based on users' known interests; 2) user exploration to identify unknown user interests or introduce users to new interests; and 3) online exploration to utilize real-time user feedback to reduce extrapolation errors in performing system and user exploration. We discuss the challenges in measurements and optimization in different types of exploration, and propose initial solutions. We showcase how each aspect of exploration contributes to the long term user experience through offline and live experiments on industrial recommendation platforms. We hope this talk can inspire more follow up work in understanding and improving exploration in recommender systems.
A Personalized Cross-Platform Post Style Transfer Method Based on Transformer and Bi-Attention Mechanism
Authors: Zhuo Chen, Baoxi Liu, Peng Zhang, Tun Lu, Hansu Gu, Ning Gu
Venue: WSDM
Year: 2022

To meet different social purposes, users usually share content related to the same topic or event to multiple social media platforms (cross-platform content sharing). As the differences of social norms and audiences among these social ecosystems, there are differences in the use of words and expressions in different platforms, resulting in different language styles among different platforms. In reality, it is usually difficult for users to grasp the consistency between the language style of posts to be published and that of a platform as the problem of context collapse. To address this problem, firstly, we conduct an study to investigate users' content sharing practices across two Chinese popular social media platforms (Douban and Weibo). The results indicate that: 1) there are significant linguistic differences between different platforms; 2) users' content sharing practices are personalized, and the style of their newly shared content is correlated with their historical posts. Secondly, based on the above findings, we propose a personalized cross-platform post style transfer model. The model can automatically transfer users' posts from one platform's language style to the target platform's language style, while preserving the content and reflecting users' personalized characteristics as much as possible. Experiments on the datasets collected from Douban and Weibo show that our model generally outperforms other comparison models on both style transfer and personalization metrics.
Estimating Causal Effects of Multi-Aspect Online Reviews with Multi-Modal Proxies
Authors: Lu Cheng, Ruocheng Guo, Huan Liu
Venue: WSDM
Year: 2022

Online reviews enable consumers to engage with companies and provide important feedback. Due to the complexity of the high-dimensional text, these reviews are often simplified as a single numerical score, e.g., ratings or sentiment scores. This work empirically examines the causal effects of user-generated online reviews on a granular level: we consider multiple aspects, e.g., the Food and Service of a restaurant. Understanding consumers' opinions toward different aspects can help evaluate business performance in detail and strategize business operations effectively. Specifically, we aim to answer interventional questions such as What will the restaurant popularity be if the quality w.r.t. its aspect Service is increased by 10%? The defining challenge of causal inference with observational data is the presence of "confounder'', which might not be observed or measured, e.g., consumers' preference to food type, rendering the estimated effects biased and high-variance. To address this challenge, we have recourse to the multi-modal proxies such as the consumer profile information and interactions between consumers and businesses. We show how to effectively leverage the rich information to identify and estimate causal effects of multiple aspects embedded in online reviews. Empirical evaluations on synthetic and real-world data corroborate the efficacy and shed light on the actionable insight of the proposed approach.
Improving Text Generation via Neural Discourse Planning
Authors: Alexander Chernyavskiy
Venue: WSDM
Year: 2022

Recent Transformer-based approaches to NLG like GPT-2 can generate syntactically coherent original texts. However, these generated texts have serious flaws. One of them is a global discourse incoherence. We present an approach to estimate the quality of discourse structure. Empirical results confirm that the discourse structure of currently generated texts is inaccurate. We propose the research directions to plan it and fill in the text in its leaves using the pipeline consisting of two GPT-based generation models. The suggested approach is universal and can be applied to different languages.
Knowledge is Power: Symbolic Knowledge Distillation, Commonsense Morality, & Multimodal Script Knowledge
Authors: Yejin Choi
Venue: WSDM
Year: 2022

Scale appears to be the winning recipe in today's AI leaderboards. And yet, extreme-scale neural models are still brittle to make errors that are often nonsensical and even counterintuitive. In this talk, I will argue for the importance of knowledge, especially commonsense knowledge, and demonstrate how smaller models developed in academia can still have an edge over larger industry-scale models, if powered with knowledge.