OpenRaiser/Intern-Atlas huggingface dataset:
Hidden Markov Contour Tree: A Spatial Structured Model for Hydrological Applications
Authors: Zhe Jiang, Arpan Man Sainju
Venue: KDD
Year: 2019

Spatial structured models are predictive models that capture dependency structure between samples based on their locations in the space. Learning such models plays an important role in many geoscience applications such as water surface mapping, but it also poses significant challenges due to implicit dependency structure in continuous space and high computational costs. Existing models often assume that the dependency structure is based on either spatial proximity or network topology, and thus cannot incorporate complex dependency structure such as contour and flow direction on a 3D potential surface. To fill the gap, this paper proposes a novel spatial structured model called hidden Markov contour tree (HMCT), which generalizes the traditional hidden Markov model from a total order sequence to a partial order polytree. HMCT also advances existing work on hidden Markov trees through capturing complex contour structures on a 3D surface. We propose efficient model construction and learning algorithms. Evaluations on real world hydrological datasets show that our HMCT outperforms multiple baseline methods in classification performance and that HMCT is scalable to large data sizes (e.g., classifying millions of samples in seconds).
Tutorial: Are You My Neighbor?: Bringing Order to Neighbor Computing Problems
Authors: David C. Anastasiu, Huzefa Rangwala, Andrea Tagarelli
Venue: KDD
Year: 2019

Finding nearest neighbors is an important topic that has attracted much attention over the years and has applications in many fields, such as market basket analysis, plagiarism and anomaly detection, community detection, ligand-based virtual screening, etc. As data are easier and easier to collect, finding neighbors has become a potential bottleneck in analysis pipelines. Performing pairwise comparisons given the massive datasets of today is no longer feasible. The high computational complexity of the task has led researchers to develop approximate methods, which find many but not all of the nearest neighbors. Yet, for some types of data, efficient exact solutions have been found by carefully partitioning or filtering the search space in a way that avoids most unnecessary comparisons. In recent years, there have been several fundamental advances in our ability to efficiently identify appropriate neighbors, especially in non-traditional data, such as graphs or document collections. In this tutorial, we provide an in-depth overview of recent methods for finding (nearest) neighbors, focusing on the intuition behind choices made in the design of those algorithms and on the utility of the methods in real-world applications. Our tutorial aims to provide a unifying view of "neighbor computing" problems, spanning from numerical data to graph data, from categorical data to sequential data, and related application scenarios. For each type of data, we will review the current state-of-the-art approaches used to identify neighbors and discuss how neighbor search methods are used to solve important problems.
Hard to Park?: Estimating Parking Difficulty at Scale
Authors: Neha Arora, James Cook, Ravi Kumar, Ivan Kuznetsov, Yechen Li, Huai-Jen Liang, Andrew Miller, Andrew Tomkins, Iveel Tsogsuren, Yi Wang
Venue: KDD
Year: 2019

In this paper we consider the problem of estimating the difficulty of parking at a particular time and place; this problem is a critical sub-component for any system providing parking assistance to users. We describe an approach to this problem that is currently in production in Google Maps, providing inferences in cities across the world. We present a wide range of features intended to capture different aspects of parking difficulty and study their effectiveness both alone and in combination. We also evaluate various model architectures for the prediction problem. Finally, we present challenges faced in estimating parking difficulty in different regions of the world, and the approaches we have taken to address them.
Fairness-Aware Machine Learning: Practical Challenges and Lessons Learned
Authors: Sarah Bird, Ben Hutchinson, Krishnaram Kenthapadi, Emre Kiciman, Margaret Mitchell
Venue: KDD
Year: 2019

Researchers and practitioners from different disciplines have highlighted the ethical and legal challenges posed by the use of machine learned models and data-driven systems, and the potential for such systems to discriminate against certain population groups, due to biases in algorithmic decision-making systems. This tutorial aims to present an overview of algorithmic bias / discrimination issues observed over the last few years and the lessons learned, key regulations and laws, and evolution of techniques for achieving fairness in machine learning systems. We will motivate the need for adopting a "fairness-first" approach (as opposed to viewing algorithmic bias / fairness considerations as an afterthought), when developing machine learning based models and systems for different consumer and enterprise applications. Then, we will focus on the application of fairness-aware machine learning techniques in practice, by highlighting industry best practices and case studies from different technology companies. Based on our experiences in industry, we will identify open problems and research challenges for the data mining / machine learning community.
Addressing Challenges in Data Science: Scale, Skill Sets and Complexity
Authors: Joseph Bradley
Venue: KDD
Year: 2019

Data science in modern applications is pushing the limits of tools and organizations. The scale of data, the breadth of required skill sets, and the complexity of workflows all cause organizations to stumble when developing data-powered applications and moving them to production. This talk will discuss these challenges and Databricks' efforts to overcome them within open source software projects like Apache Spark and MLflow. Apache Spark has simplified large-scale ETL and analytics, and its Project Hydrogen helps to bridge the gap between Spark and ML tools such as TensorFlow and Horovod. MLflow, an open source platform for managing ML lifecycles, facilitates experimentation, reproducibility and deployment. We will present insights from our collaborations on these projects, as well as our perspective at Databricks in facilitating data science for a wide variety of organizations and applications.
Friends Don't Let Friends Deploy Black-Box Models: The Importance of Intelligibility in Machine Learning
Authors: Richard Caruana
Venue: KDD
Year: 2019

Every data set is flawed, often in ways that are unanticipated and difficult to detect. If you can't understand what your model has learned, then you almost certainly are shipping models that are less accurate than they could be and which might even be risky. Historically there has been a tradeoff between accuracy and intelligibility: accurate models such as neural nets, boosted tress and random forests are not very intelligible, and intelligible models such as logistic regression and small trees or decision lists usually are less accurate. In mission-critical domains such as healthcare, where being able to understand, validate, edit and ultimately trust a model is important, one often had to choose less accurate models. But this is changing. We have developed a learning method based on generalized additive models with pairwise interactions (GA2Ms) that is as accurate as full complexity models yet even more interpretable than logistic regression. In this talk I'll highlight the kinds of problems that are lurking in all of our datasets, and how these interpretable, high-performance GAMs are making what was previously hidden, visible. I'll also show how we're using these models to uncover bias in models where fairness and transparency are important. (Code for the models has recently been released open-source.)
Adaptive Influence Maximization
Authors: Bogdan Cautis, Silviu Maniu, Nikolaos Tziortziotis
Venue: KDD
Year: 2019

Information diffusion and social influence are more and more present in today's Web ecosystem. Having algorithms that optimize the presence and message diffusion on social media is indeed crucial to all actors (media companies, political parties, corporations, etc.) who advertise on the Web. Motivated by the need for effective viral marketing strategies, influence estimation and influence maximization have therefore become important research problems, leading to a plethora of methods. However, the majority of these methods are non-adaptive, and therefore not appropriate for scenarios in which influence campaigns may be ran and observed over multiple rounds, nor for scenarios which cannot assume full knowledge over the diffusion networks and the ways information spreads in them. In this tutorial we intend to present the recent research on adaptive influence maximization,which aims to address these limitations. This can be seen as a particular case of the influence maximization problem (seeds in a social graph are selected to maximize information spread), one in which the decisions are taken as the influence campaign unfolds, over multiple rounds, and where knowledge about the graph topology and the influence process may be partial or even entirely missing. This setting, depending on the underlying assumptions, leads to variate and original approaches and algorithmic techniques, as we have witnessed in recent literature. We will review the most relevant research in this area, by organizing it along several key dimensions, and by discussing the methods' advantages and shortcomings, along with open research questions and the practical aspects of their implementation. Tutorial slides will become publicly available on https://sites.google.com/view/aim-tutorial/home.
A Robust Framework for Accelerated Outcome-driven Risk Factor Identification from EHR
Authors: Prithwish Chakraborty, Faisal Farooq
Venue: KDD
Year: 2019

Electronic Health Records (EHR) containing longitudinal information about millions of patient lives are increasingly being utilized by organizations across the healthcare spectrum. Studies on EHR data have enabled real world applications like understanding of disease progression, outcomes analysis, and comparative effectiveness research. However, often every study is independently commissioned, data is gathered by surveys or specifically purchased per study by a long and often painful process. This is followed by an arduous repetitive cycle of analysis, model building, and generation of insights. This process can take anywhere between 1 - 3 years. In this paper, we present a robust end-to-end machine learning based SaaS system to perform analysis on a very large EHR dataset. The framework consists of a proprietary EHR datamart spanning ~55 million patient lives in USA and over ~20 billion data points. To the best of our knowledge, this framework is the largest in the industry to analyze medical records at this scale, with such efficacy and ease. We developed an end-to-end ML framework with carefully chosen components to support EHR analysis at scale and suitable for further downstream clinical analysis. Specifically, it consists of a ridge regularized Survival Support Vector Machine (SSVM) with a clinical kernel, coupled with Chi-square distance-based feature selection, to uncover relevant risk factors by exploiting the weak correlations in EHR. Our results on multiple real use cases indicate that the framework identifies relevant factors effectively without expert supervision. The framework is stable, generalizable over outcomes, and also found to contribute to better out-of-bound prediction over known expert features. Importantly, the ML methodologies used are interpretable which is critical for acceptance of our system in the targeted user base. With the system being operational, all of these studies were completed within a time frame of 3-4 weeks compared to the industry standard 12-36 months. As such our system can accelerate analysis and discovery, result in better ROI due to reduced investments as well as quicker turn around of studies.
Building a Better Self-Driving Car: Hardware, Software, and Knowledge
Authors: Kumar Chellapilla
Venue: KDD
Year: 2019

Lyft's mission is to improve people's lives with the world's best transportation. Self driving vehicles have the potential to deliver unprecedented improvements to safety and quality, at a price and convenience that challenges traditional models of vehicle ownership. A combination of hardware, software, and knowledge technologies are needed to build self-driving cars. In this talk, I'll present the core problems in self-driving and how recent advances in computer vision, robotics, and machine learning are powering this revolution. The car is carefully designed with a variety of sensors that complement each other to address a wide variety of driving scenarios. Sensor fusion bring all of these signals together into an interpretable AI engine comprising of perception, prediction, planning, and controls. For example, deep learning models and large scale machine learning have closed the gap between human and machine perception. In contrast, predicting the behavior of other humans and effectively planning and negotiating maneuvers continue to be hard problems. Combining AI technologies with deep knowledge about the real world is key to addressing these.
Recent Progress in Zeroth Order Optimization and Its Applications to Adversarial Robustness in Data Mining and Machine Learning
Authors: Pin-Yu Chen, Sijia Liu
Venue: KDD
Year: 2019

Zeroth-order (ZO) optimization is increasingly embraced for solving big data and machine learning problems when explicit expressions of the gradients are difficult or infeasible to obtain. It achieves gradient-free optimization by approximating the full gradient via efficient gradient estimators. Some recent important applications include: a) generation of prediction-evasive, black-box adversarial attacks on deep neural networks, b) online network management with limited computation capacity, c) parameter inference of black-box/complex systems, and d) bandit optimization in which a player receives partial feedback in terms of loss function values revealed by her adversary. This tutorial aims to provide a comprehensive introduction to recent advances in ZO optimization methods in both theory and applications. On the theory side, we will cover convergence rate and iteration complexity analysis of ZO algorithms and make comparisons to their first-order counterparts. On the application side, we will highlight one appealing application of ZO optimization to studying the robustness of deep neural networks - practical and efficient adversarial attacks that generate adversarial examples from a black-box machine learning model. We will also summarize potential research directions regarding ZO optimization, big data challenges and some open-ended data mining and machine learning problems.
On Dynamic Network Models and Application to Causal Impact
Authors: Yu-Chia Chen, Avleen S. Bijral, Juan Lavista Ferres
Venue: KDD
Year: 2019

Dynamic extensions of Stochastic block model (SBM) are of importance in several fields that generate temporal interaction data. These models, besides producing compact and interpretable network representations, can be useful in applications such as link prediction or network forecasting. In this paper we present a conditional pseudo-likelihood based extension to dynamic SBM that can be efficiently estimated by optimizing a regularized objective. Our formulation leads to a highly scalable approach that can handle very large networks, even with millions of nodes. We also extend our formalism to causal impact for networks that allows us to quantify the impact of external events on a time dependent sequence of networks. We support our work with extensive results on both synthetic and real networks.
Effective and Efficient Reuse of Past Travel Behavior for Route Recommendation
Authors: Lisi Chen, Shuo Shang, Christian S. Jensen, Bin Yao, Zhiwei Zhang, Ling Shao
Venue: KDD
Year: 2019

With the increasing availability of moving-object tracking data, use of this data for route search and recommendation is increasingly important. To this end, we propose a novel parallel split-and-combine approach to enable route search by locations (RSL-Psc). Given a set of routes, a set of places to visit O, and a threshold θ, we retrieve the route composed of sub-routes that (i) has similarity to O no less than θ and (ii) contains the minimum number of sub-route combinations. The resulting functionality targets a broad range of applications, including route planning and recommendation, ridesharing, and location-based services in general. To enable efficient and effective RSL-Psc computation on massive route data, we develop novel search space pruning techniques and enable use of the parallel processing capabilities of modern processors. Specifically, we develop two parallel algorithms, Fully-Split Parallel Search (FSPS) and Group-Split Parallel Search (GSPS). We divide the route split-and-combine task into ∑k=0 M S(|O|,k+1) sub-tasks, where M is the maximum number of combinations and S(⋅) is the Stirling number of the second kind. In each sub-task, we use network expansion and exploit spatial similarity bounds for pruning. The algorithms split candidate routes into sub-routes and combine them to construct new routes. The sub-tasks are independent and are performed in parallel. Extensive experiments with real data offer insight into the performance of the algorithms, indicating that our RSL-Psc problem can generate high-quality results and that the two algorithms are capable of achieving high efficiency and scalability.
A Data-Driven Approach for Multi-level Packing Problems in Manufacturing Industry
Authors: Lei Chen, Xialiang Tong, Mingxuan Yuan, Jia Zeng, Lei Chen
Venue: KDD
Year: 2019

The bin packing problem is one of the most fundamental optimization problems. Owing to its hardness as a combinatorial optimization problem class and its wide range of applications in different domains, different variations of the problem are emerged and many heuristics have been proposed for obtaining approximate solutions. In this paper, we solve a Multi-Level Bin Packing (MLBP) problem in the real make-to-order industry scenario. Existing solutions are not applicable to the problem due to: 1. the final packing may consist multiple levels of sub-packings; 2. the geometry shapes of objects as well as the packing constraints may be unknown. We design an automatic packing framework which extracts the packing knowledge from historical records to support packing without geometry shape and constraint information. Furthermore, we propose a dynamic programming approach to find the optimal solution for normal size problems; and a heuristic multi-level fuzzy-matching algorithm for large size problems. An inverted index is used to accelerate strategy search. The proposed auto packing framework has been deployed in Huawei Process & Engineering System to assist the packing engineers. It achieves a performance of accelerating the execution time of processing 5,000 packing orders to about $8$ minutes with an average successful packing rate as $80.54%$, which releases at least $30%$ workloads of packing workers.
SMOILE: A Shopper Marketing Optimization and Inverse Learning Engine
Authors: Abhilash Reddy Chenreddy, Parshan Pakiman, Selvaprabu Nadarajah, Ranganathan Chandrasekaran, Rick Abens
Venue: KDD
Year: 2019

Product brands employ shopper marketing (SM) strategies to convert shoppers along the path to purchase. Traditional marketing mix models (MMMs), which leverage regression techniques and historical data, can be used to predict the component of sales lift due to SM tactics. The resulting predictive model is a critical input to plan future SM strategies. The implementation of traditional MMMs, however, requires significant ad-hoc manual intervention due to their limited flexibility in (i) explicitly capturing the temporal link between decisions; (ii) accounting for the interaction between business rules and past (sales and decision) data during the attribution of lift to SM; and (iii) ensuring that future decisions adhere to business rules. These issues necessitate MMMs with tailored structures for specific products and retailers, each requiring significant hand-engineering to achieve satisfactory performance -- a major implementation challenge. We propose an SM Optimization and Inverse Learning Engine (SMOILE) that combines optimization and inverse reinforcement learning to streamline implementation. SMOILE learns a model of lift by viewing SM tactic choice as a sequential process, leverages inverse reinforcement learning to explicitly couple sales and decision data, and employs an optimization approach to handle a wide-array of business rules. Using a unique dataset containing sales and SM spend information across retailers and products, we illustrate how SMOILE standardizes the use of data to prescribe future SM decisions. We also track an industry benchmark to showcase the importance of encoding SM lift and decision structures to mitigate spurious results when uncovering the impact of SM decisions.
Cluster-GCN: An Efficient Algorithm for Training Deep and Large Graph Convolutional Networks
Authors: Wei-Lin Chiang, Xuanqing Liu, Si Si, Yang Li, Samy Bengio, Cho-Jui Hsieh
Venue: KDD
Year: 2019

Graph convolutional network (GCN) has been successfully applied to many graph-based applications; however, training a large-scale GCN remains challenging. Current SGD-based algorithms suffer from either a high computational cost that exponentially grows with number of GCN layers, or a large space requirement for keeping the entire graph and the embedding of each node in memory. In this paper, we propose Cluster-GCN, a novel GCN algorithm that is suitable for SGD-based training by exploiting the graph clustering structure. Cluster-GCN works as the following: at each step, it samples a block of nodes that associate with a dense subgraph identified by a graph clustering algorithm, and restricts the neighborhood search within this subgraph. This simple but effective strategy leads to significantly improved memory and computational efficiency while being able to achieve comparable test accuracy with previous algorithms. To test the scalability of our algorithm, we create a new Amazon2M data with 2 million nodes and 61 million edges which is more than 5 times larger than the previous largest publicly available dataset (Reddit). For training a 3-layer GCN on this data, Cluster-GCN is faster than the previous state-of-the-art VR-GCN (1523 seconds vs 1961 seconds) and using much less memory (2.2GB vs 11.2GB). Furthermore, for training 4 layer GCN on this data, our algorithm can finish in around 36 minutes while all the existing GCN training algorithms fail to train due to the out-of-memory issue. Furthermore, Cluster-GCN allows us to train much deeper GCN without much time and memory overhead, which leads to improved prediction accuracy---using a 5-layer Cluster-GCN, we achieve state-of-the-art test F1 score 99.36 on the PPI dataset, while the previous best result was 98.71 by~\citezhang2018gaan.