Statistical Learning
Learning Topics using Semantic Locality
Zhao, Ziyi, Pugdeethosapol, Krittaphat, Lin, Sheng, Li, Zhe, Ding, Caiwen, Wang, Yanzhi, Qiu, Qinru
The topic modeling discovers the latent topic probability of the given text documents. To generate the more meaningful topic that better represents the given document, we proposed a new feature extraction technique which can be used in the data preprocessing stage. The method consists of three steps. First, it generates the word/word-pair from every single document. Second, it applies a two-way TF-IDF algorithm to word/word-pair for semantic filtering. Third, it uses the K-means algorithm to merge the word pairs that have the similar semantic meaning. Experiments are carried out on the Open Movie Database (OMDb), Reuters Dataset and 20NewsGroup Dataset. The mean Average Precision score is used as the evaluation metric. Comparing our results with other state-of-the-art topic models, such as Latent Dirichlet allocation and traditional Restricted Boltzmann Machines. Our proposed data preprocessing can improve the generated topic accuracy by up to 12.99\%.
Personalized Dynamics Models for Adaptive Assistive Navigation Interfaces
Ohn-Bar, Eshed, Kitani, Kris, Asakawa, Chieko
We explore the role of personalization for assistive navigational systems (e.g., service robot, wearable system or smartphone app) that guide visually impaired users through speech, sound and haptic-based instructional guidance. Based on our analysis of real-world users, we show that the dynamics of blind users cannot be accounted for by a single universal model but instead must be learned on an individual basis. To learn personalized instructional interfaces, we propose PING (Personalized INstruction Generation agent), a model-based reinforcement learning framework which aims to quickly adapt its state transition dynamics model to match the reactions of the user using a novel end-to-end learned weighted majority-based regression algorithm. In our experiments, we show that PING learns dynamics models significantly faster compared to baseline transfer learning approaches on real-world data. We find that through better reasoning over personal mobility nuances, interaction with surrounding obstacles, and the current navigation task, PING is able to improve the performance of instructional assistive navigation at the most crucial junctions such as turns or veering paths. To enable sufficient planning time over user responses, we emphasize prediction of human motion for long horizons. Specifically, the learned dynamics models are shown to consistently improve long-term position prediction by over 1 meter on average (nearly the width of a hallway) compared to baseline approaches even when considering a prediction horizon of 20 seconds into the future.
Estimating Time-Varying Graphical Models
In this paper, we study time-varying graphical models based on data measured over a temporal grid. Such models are motivated by the needs to describe and understand evolving interacting relationships among a set of random variables in many real applications, for instance the study of how stocks interact with each other and how such interactions change over time. We propose a new model, LOcal Group Graphical Lasso Estimation (loggle), under the assumption that the graph topology changes gradually over time. Specifically, loggle uses a novel local group-lasso type penalty to efficiently incorporate information from neighboring time points and to impose structural smoothness of the graphs. We implement an ADMM based algorithm to fit the loggle model. This algorithm utilizes blockwise fast computation and pseudo-likelihood approximation to improve computational efficiency. An R package loggle has also been developed. We evaluate the performance of loggle by simulation experiments. We also apply loggle to S&P 500 stock price data and demonstrate that loggle is able to reveal the interacting relationships among stocks and among industrial sectors in a time period that covers the recent global financial crisis.
Adafactor: Adaptive Learning Rates with Sublinear Memory Cost
Shazeer, Noam, Stern, Mitchell
In several recently proposed stochastic optimization methods (e.g. RMSProp, Adam, Adadelta), parameter updates are scaled by the inverse square roots of exponential moving averages of squared past gradients. Maintaining these per-parameter second-moment estimators requires memory equal to the number of parameters. For the case of neural network weight matrices, we propose maintaining only the per-row and per-column sums of these moving averages, and estimating the per-parameter second moments based on these sums. We demonstrate empirically that this method produces similar results to the baseline. Secondly, we show that adaptive methods can produce larger-than-desired updates when the decay rate of the second moment accumulator is too slow. We propose update clipping and a gradually increasing decay rate scheme as remedies. Combining these methods and dropping momentum, we achieve comparable results to the published Adam regime in training the Transformer model on the WMT 2014 English-German machine translation task, while using very little auxiliary storage in the optimizer. Finally, we propose scaling the parameter updates based on the scale of the parameters themselves.
Introduction to ML Classification Models using scikit-learn
This course will give you a fundamental understanding of Machine Learning overall with a focus on building classification models. Basic ML concepts of ML are explained, including Supervised and Unsupervised Learning; Regression and Classification; and Overfitting. There are 3 lab sections which focus on building classification models using Support Vector Machines, Decision Trees and Random Forests using real data sets. The implementation will be performed using the scikit-learn library for Python. The Intro to ML Classification Models course is meant for developers or data scientists (or anybody else) who knows basic Python programming and wishes to learn about Machine Learning, with a focus on solving the problem of classification.
Machine learning offers new way of designing chiral crystals: Logistic regression analysis model predicts ideal chiral crystal
Chirality describes the quality of possessing a mirror image to something else, but without the ability to superimpose it. Your left foot, for example, is a mirror of your right. They look similar, but they are not the same. This is why you cannot wear a left shoe on your right foot. The idea is similar in chemistry.
Machine Learning with C Udemy
ML has become a fundamental part of the 21st century; from Netflix recommendations to fraud detection, ML is ever- present in our daily lives. At its roots, ML effectively applies statistics and pattern recognition, we will use these ideas to help solve a range of modern-day problems. C is a very fast language to execute your code and is extensively used when your final "models" are being deployed. If you want to run a program, with a lot of array calculation then C should be your weapon of choice. This course will start off with a broad overview of ML and the varying methods associated with it.
Machine learning offers new way of designing chiral crystals
Engineers and chemists at Hiroshima University successfully used the same technology at the core of facial recognition to design chiral crystals. This is the first study reporting the use of this technology, called logistic regression analysis, to predict which chemical groups are best for making chiral molecules. Results were published in Chemistry Letters. Chirality describes the quality of possessing a mirror image to something else, but without the ability to superimpose it. Your left foot, for example, is a mirror of your right.
The Ultimate Unity Games & Python Artificial Intelligence
In Part 1 - Glauco Pires from Mammoth Interactive will teach you how to build a game in Unity . Learn to code, make art and add sound to build a full 2D Double Dragoon game in Unity 2017. You will learn the fundamentals of designing, coding, and fine-tuning a game. You will design the game and its functionality in Unity and learn how to code in C#. Don't worry if you've never coded before!
Learn Python and R In Data Science - 2018 Udemy
Any data analysts who want to level up in Machine Learning. Students who have at least high school knowledge in math and who want to start learning Machine Learning. Any intermediate level people who know the basics of machine learning, including the classical algorithms like linear regression or logistic regression, but who want to learn more about it and explore all the different fields of Machine Learning. Any people who are not that comfortable with coding but who are interested in Machine Learning and want to apply it easily on datasets Any people who want to create added value to their business by using powerful Machine Learning tools. Any data analysts who want to level up in Machine Learning.