Inductive Learning
Large-scale Validation of Counterfactual Learning Methods: A Test-Bed
Lefortier, Damien, Swaminathan, Adith, Gu, Xiaotao, Joachims, Thorsten, de Rijke, Maarten
The ability to perform effective off-policy learning would revolutionize the process of building better interactive systems, such as search engines and recommendation systems for e-commerce, computational advertising and news. Recent approaches for off-policy evaluation and learning in these settings appear promising. With this paper, we provide real-world data and a standardized test-bed to systematically investigate these algorithms using data from display advertising. In particular, we consider the problem of filling a banner ad with an aggregate of multiple products the user may want to purchase. This paper presents our test-bed, the sanity checks we ran to ensure its validity, and shows results comparing state-of-the-art off-policy learning methods like doubly robust optimization, POEM, and reductions to supervised learning using regression baselines. Our results show experimental evidence that recent off-policy learning methods can improve upon state-of-the-art supervised learning techniques on a large-scale real-world data set.
L.A. County median home price breaks record set during last decade's housing boom
In summer 2007, the Los Angeles County median home price hit an all-time high of $550,000. It soon plunged as the housing bubble burst and the national economy crashed. Now the median, the point where half the homes sold for more and half for less, has finally passed the heights of 10 years ago -- the result of an improving economy, historically low mortgage rates and a shortage of listings. According to a report released Wednesday from real estate firm CoreLogic, the county's median price in May rose 6.8% from a year earlier to reach $560,500 as sales jumped 4.8%. When adjusted for inflation, May's median remains 11% below the 2007 high, though the nominal record comes amid fresh concerns over the high cost of housing in California.
Deep Counterfactual Networks with Propensity-Dropout
Alaa, Ahmed M., Weisz, Michael, van der Schaar, Mihaela
We propose a novel approach for inferring the individualized causal effects of a treatment (intervention) from observational data. Our approach conceptualizes causal inference as a multitask learning problem; we model a subject's potential outcomes using a deep multitask network with a set of shared layers among the factual and counterfactual outcomes, and a set of outcome-specific layers. The impact of selection bias in the observational data is alleviated via a propensity-dropout regularization scheme, in which the network is thinned for every training example via a dropout probability that depends on the associated propensity score. The network is trained in alternating phases, where in each phase we use the training examples of one of the two potential outcomes (treated and control populations) to update the weights of the shared layers and the respective outcome-specific layers. Experiments conducted on data based on a real-world observational study show that our algorithm outperforms the state-of-the-art.
Bayesian Conditional Generative Adverserial Networks
Abbasnejad, M. Ehsan, Shi, Qinfeng, Abbasnejad, Iman, Hengel, Anton van den, Dick, Anthony
Traditional GANs use a deterministic generator function (typically a neural network) to transform a random noise input $z$ to a sample $\mathbf{x}$ that the discriminator seeks to distinguish. We propose a new GAN called Bayesian Conditional Generative Adversarial Networks (BC-GANs) that use a random generator function to transform a deterministic input $y'$ to a sample $\mathbf{x}$. Our BC-GANs extend traditional GANs to a Bayesian framework, and naturally handle unsupervised learning, supervised learning, and semi-supervised learning problems. Experiments show that the proposed BC-GANs outperforms the state-of-the-arts.
Generative Models & Variational AutoEncoder Explained โ Frank's World
The ever-increasing size of modern datasets combined with the difficulty of obtaining labeled information has made semi-supervised learning one of the problems of significant practical importance in modern data analysis. VAE offers a novel way to enforce structure on the representation surface, by doing so, it opens the possibility of employing traditional semi supervised learning techniques on the structured embedding space. In this talk, Shair Harel covers how VAE imposes latent space structure constraint, and how we can use it in a semi-supervised settings.
Shrinking data for surgical training
Laparoscopy is a surgical technique in which a fiber-optic camera is inserted into a patient's abdominal cavity to provide a video feed that guides the surgeon through a minimally invasive procedure. Laparoscopic surgeries can take hours, and the video generated by the camera -- the laparoscope -- is often recorded. Those recordings contain a wealth of information that could be useful for training both medical providers and computer systems that would aid with surgery, but because reviewing them is so time consuming, they mostly sit idle. Researchers at MIT and Massachusetts General Hospital hope to change that, with a new system that can efficiently search through hundreds of hours of video for events and visual features that correspond to a few training examples. In work they presented at the International Conference on Robotics and Automation this month, the researchers trained their system to recognize different stages of an operation, such as biopsy, tissue removal, stapling, and wound cleansing.
Renewable Energy Record Set in U.S.
Solar panels stand at the Ivanpah Solar Electric Generating System in the Mojave Desert near Primm, Nevada in 2014. California and Arizona by far generate the most electricity with solar power in the U.S. The U.S. set a new renewable energy milestone in March, in data released Wednesday. For the first time, wind and solar accounted for 10 percent of all electricity generation, with wind comprising 8 percent and solar coming in at 2 percent. The report was published by the U.S. Energy Information Administration (EIA), which collects and disseminates environmental data that is used to inform policymakers. Wind and solar generation typically peaks in the spring and fall when there is less energy demand, and the EIA expects April to continue the record-setting 10 percent trend.
A Supervised Approach to Extractive Summarisation of Scientific Papers
Collins, Ed, Augenstein, Isabelle, Riedel, Sebastian
Automatic summarisation is a popular approach to reduce a document to its main arguments. Recent research in the area has focused on neural approaches to summarisation, which can be very data-hungry. However, few large datasets exist and none for the traditionally popular domain of scientific publications, which opens up challenging research avenues centered on encoding large, complex documents. In this paper, we introduce a new dataset for summarisation of computer science publications by exploiting a large resource of author provided summaries and show straightforward ways of extending it further. We develop models on the dataset making use of both neural sentence encoding and traditionally used summarisation features and show that models which encode sentences as well as their local and global context perform best, significantly outperforming well-established baseline methods.
Multiple Instance Dictionary Learning for Beat-to-Beat Heart Rate Monitoring from Ballistocardiograms
Jiao, Changzhe, Su, Bo-Yu, Lyons, Princess, Zare, Alina, Ho, K. C., Skubic, Marjorie
Abstract--A multiple instance dictionary learning approach, Dictionary Learning using Functions of Multiple Instances (DL-FUMI), is used to perform beat-to-beat heart rate estimation and to characterize heartbeat signatures from ballistocardiogram (BCG) signals collected with a hydraulic bed sensor. DL-FUMI estimates a "heartbeat concept" that represents an individual's personal ballistocardiogram heartbeat pattern. DL-FUMI formulates heartbeat detection and heartbeat characterization as a multiple instance learning problem to address the uncertainty inherent in aligning BCG signals with ground truth during training. Experimental results show that the estimated heartbeat concept found by DL-FUMI is an effective heartbeat prototype and achieves superior performance over comparison algorithms. I. INTRODUCTION Increasingly more and more devices for realtime heart rate monitoring are becoming available. However, the majority of these devices are intrusive and require continual interaction. For example many heart rate monitoring systems require a user to physically wear the system ( e.g., as a watch, chest strap, electrodes, finger sensor, etc.) and/or charge batteries frequently. In contrast, devices that use ballistocardiography can provide an unintrusive and, thus, relatively low maintenance, comfortable alternative for heart rate monitoring. These sensing systems record the motion of the human body generated by the sudden ejection of blood into the large vessels at each cardiac cycle [1]. Such motion contains rich information and has gained revived interest due to recent development in measurement technology [2, 3] and a growing interest in managing chronic health conditions through passive sensors in the home [4].