Inductive Learning
Supervised learning through the lens of compression
David, Ofir, Moran, Shay, Yehudayoff, Amir
This work continues the study of the relationship between sample compression schemes and statistical learning, which has been mostly investigated within the framework of binary classification. We first extend the investigation to multiclass categorization: we prove that in this case learnability is equivalent to compression of logarithmic sample size and that the uniform convergence property implies compression of constant size. We use the compressibility-learnability equivalence to show that (i) for multiclass categorization, PAC and agnostic PAC learnability are equivalent, and (ii) to derive a compactness theorem for learnability. We then consider supervised learning under general loss functions: we show that in this case, in order to maintain the compressibility-learnability equivalence, it is necessary to consider an approximate variant of compression. We use it to show that PAC and agnostic PAC are not equivalent, even when the loss function has only three values.
Stochastic Structured Prediction under Bandit Feedback
Sokolov, Artem, Kreutzer, Julia, Riezler, Stefan, Lo, Christopher
Stochastic structured prediction under bandit feedback follows a learning protocol where on each of a sequence of iterations, the learner receives an input, predicts an output structure, and receives partial feedback in form of a task loss evaluation of the predicted structure. We present applications of this learning scenario to convex and non-convex objectives for structured prediction and analyze them as stochastic first-order methods. We present an experimental evaluation on problems of natural language processing over exponential output spaces, and compare convergence speed across different objectives under the practical criterion of optimal task performance on development data and the optimization-theoretic criterion of minimal squared gradient norm. Best results under both criteria are obtained for a non-convex objective for pairwise preference learning under bandit feedback.
Adaptive Smoothed Online Multi-Task Learning
Murugesan, Keerthiram, Liu, Hanxiao, Carbonell, Jaime, Yang, Yiming
This paper addresses the challenge of jointly learning both the per-task model parameters and the inter-task relationships in a multi-task online learning setting. The proposed algorithm features probabilistic interpretation, efficient updating rules and flexible modulation on whether learners focus on their specific task or on jointly address all tasks. The paper also proves a sub-linear regret bound as compared to the best linear predictor in hindsight. Experiments over three multi-task learning benchmark datasets show advantageous performance of the proposed approach over several state-of-the-art online multi-task learning baselines.
A Consistent Regularization Approach for Structured Prediction
Ciliberto, Carlo, Rosasco, Lorenzo, Rudi, Alessandro
We propose and analyze a regularization approach for structured prediction problems. We characterize a large class of loss functions that allows to naturally embed structured outputs in a linear space. We exploit this fact to design learning algorithms using a surrogate loss approach and regularization techniques. We prove universal consistency and finite sample bounds characterizing the generalization properties of the proposed method. Experimental results are provided to demonstrate the practical usefulness of the proposed approach.
RSSL: Semi-supervised Learning in R
In this paper, we introduce a package for semi-supervised learning research in the R programming language called RSSL. We cover the purpose of the package, the methods it includes and comment on their use and implementation. We then show, using several code examples, how the package can be used to replicate well-known results from the semi-supervised learning literature.
A real quick snooze! New record set for the world's fastest BED - as modified vehicle clocks 84mph on the race track
New record set for the world's fastest BED with motorised mattress clocking 84mph on a race track Engineers were commissioned by a hotel booking site to build a motorised bed British racing diver Tom Onslow-Cole, 29, took the piece of furniture for a spin He broke the Guinness World Record for the World's Fastest Bed at 83.8mph He broke the Guinness World Record for the World's Fastest Bed at 83.8mph British racing diver Tom Onslow-Cole, 29, took the piece of furniture for a spin and broke the Guinness World Record for the World's Fastest Bed, clocking 84mph The do's and don'ts of aprรจs-ski revealed (including why... Aviation expert reveals how to travel in luxury on a... The do's and don'ts of aprรจs-ski revealed (including why... Aviation expert reveals how to travel in luxury on a... Crossing the finish line: Adjudicators clocked it whooshing forwards at 83.8 mph A wheely great sleep: Onslow-Cole said his speedy snooze was an'unforgettable experience'. He added: 'I hope it'll stand the test of time โ it'll take some beating!' Woman goes on racist rant while waiting in line at J.C. Penney Black blues musician explores racism by befriending the KKK A young thug is filmed fly kicking a lady in the back Dramatic moment man removed from flight for'speaking Arabic' GRAPHIC: Robber is left writhing on the pavement after shot out Syrian police injured after girl blows herself up inside station Male guests in a Chinese wedding flock to harass a bridesmaid Angela Rye shares video of her invasive ordeal with TSA agent Body cam footage shows moments before two Georgia cops are shot Boeing cargo plane overshoots runway before crashing in Colombia Shocking video shows a Texas mother hitting her daughter Adorable moment puppy excitedly unwraps Christmas present Woman goes on racist rant while waiting in line at J.C. Penney Dramatic moment man removed from flight for'speaking Arabic' Is resting your head on a BOX the best way to sleep on a... Shocking pictures reveal how some of the most picturesque... Choose the right seat, alter your watch and drink alcohol:... Fascinating images capture the... Should you be worried about flying in the snow? When photographers were asked to submit their best holiday... 'Is this a real picture?
3D Generative Adversarial Network
We study the problem of 3D object generation. We propose a novel framework, namely 3D Generative Adversarial Network (3D-GAN), which generates 3D objects from a probabilistic space by leveraging recent advances in volumetric convolutional networks and generative adversarial nets. The benefits of our model are three-fold: first, the use of an adversarial criterion, instead of traditional heuristic criteria, enables the generator to capture object structure implicitly and to synthesize high-quality 3D objects; second, the generator establishes a mapping from a low-dimensional probabilistic space to the space of 3D objects, so that we can sample objects without a reference image or CAD models, and explore the 3D object manifold; third, the adversarial discriminator provides a powerful 3D shape descriptor which, learned without supervision, has wide applications in 3D object recognition. Experiments demonstrate that our method generates high-quality 3D objects, and our unsupervisedly learned features achieve impressive performance on 3D object recognition, comparable with those of supervised learning methods.
Improving Predictions with Ensemble Model
"Alone we can do so little and together we can do much" - a phrase from Helen Keller during 50's is a reflection of achievements and successful stories in real life scenarios from decades. Same thing applies with most of the cases from innovation with big impacts and with advanced technologies world. The machine Learning domain is also in the same race to make predictions and classification in a more accurate way using so called ensemble method and it is proved that ensemble modeling offers one of the most convincing way to build highly accurate predictive models. Ensemble methods are learning models that achieve performance by combining the opinions of multiple learners. Typically, an ensemble model is a supervised learning technique for combining multiple weak learners or models to produce a strong learner with the concept of Bagging and Boosting for data sampling.
Hierarchical Partitioning of the Output Space in Multi-label Data
Papanikolaou, Yannis, Katakis, Ioannis, Tsoumakas, Grigorios
Hierarchy Of Multi-label classifiers (HOMER) is a multi-label learning algorithm that breaks the initial learning task to several, easier sub-tasks by first constructing a hierarchy of labels from a given label set and secondly employing a given base multi-label classifier (MLC) to the resulting sub-problems. The primary goal is to effectively address class imbalance and scalability issues that often arise in real-world multi-label classification problems. In this work, we present the general setup for a HOMER model and a simple extension of the algorithm that is suited for MLCs that output rankings. Furthermore, we provide a detailed analysis of the properties of the algorithm, both from an aspect of effectiveness and computational complexity. A secondary contribution involves the presentation of a balanced variant of the k means algorithm, which serves in the first step of the label hierarchy construction. We conduct extensive experiments on six real-world datasets, studying empirically HOMER's parameters and providing examples of instantiations of the algorithm with different clustering approaches and MLCs, The empirical results demonstrate a significant improvement over the given base MLC.