Country
Survival Prediction by an Integrated Learning Criterion on Intermittently Varying Healthcare Data
Zhang, Jianfei (University of Sherbrooke) | Chen, Lifei (Fujian Normal University) | Vanasse, Alain (University of Sherbrooke) | Courteau, Josiane ( University of Sherbrooke ) | Wang, Shengrui ( University of Sherbrooke )
Survival prediction is crucial to healthcare research, but is confined primarily to specific types of data involving only the present measurements. This paper considers the more general class of healthcare data found in practice, which includes a wealth of intermittently varying historical measurements in addition to the present measurements. Making survival predictions on such data bristles with challenges to the existing prediction models. For this reason, we propose a new semi-proportional hazards model using locally time-varying coefficients, and a novel complete-data model learning criterion for coefficient optimization. Experiments on the healthcare data demonstrate the effectiveness and generalizability of our model and its promise in practical applications.
Social Role-Aware Emotion Contagion in Image Social Networks
Yang, Yang (Tsinghua University) | Jia, Jia (Tsinghua University) | Wu, Boya (Tsinghua Univeristy) | Tang, Jie (Tsinghua University)
Psychological theories suggest that emotion represents the state of mind and instinctive responses of oneโs cognitive system (Cannon 1927). Emotions are a complex state of feeling that results in physical and psychological changes that influence our behavior. In this paper, we study an interesting problem of emotion contagion in social networks. In particular, by employing an image social network (Flickr) as the basis of our study, we try to unveil how usersโ emotional statuses influence each other and how usersโ positions in the social network affect their influential strength on emotion. We develop a probabilistic framework to formalize the problem into a role-aware contagion model. The model is able to predict usersโ emotional statuses based on their historical emotional statuses and social structures. Experiments on a large Flickr dataset show that the proposed model significantly outperforms (+31% in terms of F1-score) several alternative methods in predicting usersโ emotional status. We also discover several intriguing phenomena. For example, the probability that a user feels happy is roughly linear to the number of friends who are also happy; but taking a closer look, the happiness probability is superlinear to the number of happy friends who act as opinion leaders (Page et al. 1999) in the network and sublinear in the number of happy friends who span structural holes (Burt 2001). This offers a new opportunity to understand the underlying mechanism of emotional contagion in online social networks.
MUST-CNN: A Multilayer Shift-and-Stitch Deep Convolutional Architecture for Sequence-Based Protein Structure Prediction
Lin, Zeming (University of Virginia) | Lanchantin, Jack (University of Virginia) | Qi, Yanjun (University of Virginia)
Predicting protein properties such as solvent accessibility and secondary structure from its primary amino acid sequence is an important task in bioinformatics. Recently, a few deep learning models have surpassed the traditional window based multilayer perceptron. Taking inspiration from the image classification domain we propose a deep convolutional neural network architecture, MUST-CNN, to predict protein properties. This architecture uses a novel multilayer shift-and-stitch (MUST) technique to generate fully dense per-position predictions on protein sequences. Our model is significantly simpler than the state-of-the-art, yet achieves better results. By combining MUST and the efficient convolution operation, we can consider far more parameters while retaining very fast prediction speeds. We beat the state-of-the-art performance on two large protein property prediction datasets.
Little Is Much: Bridging Cross-Platform Behaviors through Overlapped Crowds
Jiang, Meng (Tsinghua University) | Cui, Peng (Tsinghua University) | Yuan, Nicholas Jing (Microsoft Research Asia) | Xie, Xing (Microsoft Research Asia) | Yang, Shiqiang (Tsinghua University)
People often use multiple platforms to fulfill their different information needs. With the ultimate goal of serving people intelligently, a fundamental way is to get comprehensive understanding about user needs. How to organically integrate and bridge cross-platform information in a human-centric way is important. Existing transfer learning assumes either fully-overlapped or non-overlapped among the users. However, the real case is the users of different platforms are partially overlapped. The number of overlapped users is often small and the explicitly known overlapped users is even less due to the lacking of unified ID for a user across different platforms. In this paper, we propose a novel semi-supervised transfer learning method to address the problem of cross-platform behavior prediction, called XPTrans. To alleviate the sparsity issue, it fully exploits the small number of overlapped crowds to optimally bridge a user's behaviors in different platforms. Extensive experiments across two real social networks show that XPTrans significantly outperforms the state-of-the-art. We demonstrate that by fully exploiting 26% overlapped users, XPTrans can predict the behaviors of non-overlapped users with the same accuracy as overlapped users, which means the small overlapped crowds can successfully bridge the information across different platforms.
Scaling-up Empirical Risk Minimization: Optimization of Incomplete U-statistics
Clรฉmenรงon, Stรฉphan, Bellet, Aurรฉlien, Colin, Igor
In a wide range of statistical learning problems such as ranking, clustering or metric learning among others, the risk is accurately estimated by $U$-statistics of degree $d\geq 1$, i.e. functionals of the training data with low variance that take the form of averages over $k$-tuples. From a computational perspective, the calculation of such statistics is highly expensive even for a moderate sample size $n$, as it requires averaging $O(n^d)$ terms. This makes learning procedures relying on the optimization of such data functionals hardly feasible in practice. It is the major goal of this paper to show that, strikingly, such empirical risks can be replaced by drastically computationally simpler Monte-Carlo estimates based on $O(n)$ terms only, usually referred to as incomplete $U$-statistics, without damaging the $O_{\mathbb{P}}(1/\sqrt{n})$ learning rate of Empirical Risk Minimization (ERM) procedures. For this purpose, we establish uniform deviation results describing the error made when approximating a $U$-process by its incomplete version under appropriate complexity assumptions. Extensions to model selection, fast rate situations and various sampling techniques are also considered, as well as an application to stochastic gradient descent for ERM. Finally, numerical examples are displayed in order to provide strong empirical evidence that the approach we promote largely surpasses more naive subsampling techniques.
Infographic: Are consumers ready for driverless cars and AI?
Driverless car technology has been one of the most anticipated disruptions of a major global industry. Beginning with Google in 2010, the field has expanded to include other tech companies and auto manufacturers, including Uber, Lyft, Tesla, and General Motors. With so many companies jostling to be among the first to integrate artificial intelligence into the world's billion-plus automobiles, the speed with which the wider industry is expected to adopt these cutting edge technologies is impressive. By 2021, sales of connected car technologies are predicted to triple to almost 180 billion. It is not difficult to see why the driverless car industry shows such promise. The anticipated benefits of the technology are numerous, including fewer road accidents, reduced congestion, cheaper public transportation, and lower greenhouse gas emissions.
Startup junkie advice for both entrepreneurs and enterprises - IBM Watson
Not every startup CEO can say they were able to grow their business to a point where they were acquired. Even fewer can say they did it twice. But that is exactly the case for AlchemyAPI Founder and CEO Elliot Turner. Turner launched his first startup, MimeStar, a software development company focused on network intrusion detection, while a sophomore in high school. Inc. acquired it by the time he was twenty-one. He quickly saw the shift in the market to the need to democratize artificial intelligence (A.I.), and decided to venture out on his own to start AlchemyAPI.
5 Artificial Intelligence Services Every Salesperson Should Try to Boost Their Sales
Artificial Intelligence is all over the news these days with companies like Google, Facebook and Apple investing heavily, but it can be hard for individual salespeople and entrepreneurs to know which services they can use without the need of a large IT staff or a corporate approval process. These services offer something unique like helping to find the right prospect to follow-up with, scheduling a meeting or finding insight on a customer. In each case, these services do not require any IT knowledge for setup, management, or maintenance. How many times have you engaged a prospect, but it took a large number of emails back and forth to schedule that next meeting? Instead you can use X.ai's assistant'Amy' who connects to your calendar and emails your contact on your behalf. She proposes free times and will send out calendar invites once an agreement on time and place has been met.
Chinese scientists built a 'robot goddess', then made it subservient and insecure
An ultra-realistic robot was unveiled last week by researchers from the University of Science and Technology in China (USTC). Jia Jia, as the female robot has been named, is apparently capable of basic communication, interaction with nearby people, and natural facial expressions. Unfortunately, many of her pre-programmed interactions appear to be highly stereotypical.
The Real Reason AI Won't Take Over Anytime Soon
Artificial intelligence has had its share of ups and downs recently. In what was widely seen as a key milestone for artificial intelligence (AI) researchers, one system beat a former world champion at a mind-bendingly intricate board game. But then, just a week later, a "chatbot" that was designed to learn from its interactions with humans on Twitter had a highly public racist meltdown on the social networking site. How did this happen, and what does it mean for the dynamic field of AI? In early March, a Google-made artificial intelligence system beat former world champ Lee Sedol four matches to one at an ancient Chinese game, called Go, that is considered more complex than chess, which was previously used as a benchmark to assess progress in machine intelligence.