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Making the Cut: A Bandit-based Approach to Tiered Interviewing

arXiv.org Artificial Intelligence

Given a huge set of applicants, how should a firm allocate sequential resume screenings, phone interviews, and in-person site visits? In a tiered interview process, later stages (e.g., in-person visits) are more informative, but also more expensive than earlier stages (e.g., resume screenings). Using accepted hiring models and the concept of structured interviews, a best practice in human resources, we cast tiered hiring as a combinatorial pure exploration (CPE) problem in the stochastic multi-armed bandit setting. The goal is to select a subset of arms (in our case, applicants) with some combinatorial structure. We present new algorithms in both the probably approximately correct (PAC) and fixed-budget settings that select a near-optimal cohort with provable guarantees. We show on real data from one of the largest USbased computer science graduate programs that our algorithms make better hiring decisions or use less budget than the status quo. '... nothing we do is more important than hiring and developing people. At the end of the day, you bet on people, not on strategies." - Lawrence Bossidy, The CEO as Coach (1995)


Adversarial Computation of Optimal Transport Maps

arXiv.org Machine Learning

Computing optimal transport maps between high-dimensional and continuous distributions is a challenging problem in optimal transport (OT). Generative adversarial networks (GANs) are powerful generative models which have been successfully applied to learn maps across high-dimensional domains. However, little is known about the nature of the map learned with a GAN objective. To address this problem, we propose a generative adversarial model in which the discriminator's objective is the $2$-Wasserstein metric. We show that during training, our generator follows the $W_2$-geodesic between the initial and the target distributions. As a consequence, it reproduces an optimal map at the end of training. We validate our approach empirically in both low-dimensional and high-dimensional continuous settings, and show that it outperforms prior methods on image data.


Sequential estimation of quantiles with applications to A/B-testing and best-arm identification

arXiv.org Machine Learning

Consider the problem of sequentially estimating quantiles of any distribution over a complete, fully-ordered set, based on a stream of i.i.d. observations. We propose new, theoretically sound and practically tight confidence sequences for quantiles, that is, sequences of confidence intervals which are valid uniformly over time. We give two methods for tracking a fixed quantile and two methods for tracking all quantiles simultaneously. Specifically, we provide explicit expressions with small constants for intervals whose widths shrink at the fastest possible $\sqrt{t^{-1} \log\log t}$ rate, as determined by the law of the iterated logarithm (LIL). As a byproduct, we give a non-asymptotic concentration inequality for the empirical distribution function which holds uniformly over time with the LIL rate, thus strengthening Smirnov's asymptotic empirical process LIL, and extending the famed Dvoretzky-Kiefer-Wolfowitz (DKW) inequality to hold uniformly over all sample sizes while only being about twice as wide in practice. This inequality directly yields sequential analogues of the one- and two-sample Kolmogorov-Smirnov tests, and a test of stochastic dominance. We apply our results to the problem of selecting an arm with an approximately best quantile in a multi-armed bandit framework, proving a state-of-the-art sample complexity bound for a novel allocation strategy. Simulations demonstrate that our method stops with fewer samples than existing methods by a factor of five to fifty. Finally, we show how to compute confidence sequences for the difference between quantiles of two arms in an A/B test, along with corresponding always-valid $p$-values.


A robot's sense-making of fallacies and rhetorical tropes. Creating ontologies of what humans try to say

arXiv.org Artificial Intelligence

In the design of user-friendly robots, human communication should be understood by the system beyond mere logics and literal meaning. Robot communication-design has long ignored the importance of communication and politeness rules that are 'forgiving' and 'suspending disbelief' and cannot handle the basically metaphorical way humans design their utterances. Through analysis of the psychological causes of illogical and non-literal statements, signal detection, fundamental attribution errors, and anthropomorphism, we developed a fail-safe protocol for fallacies and tropes that makes use of Frege's distinction between reference and sense, Beth's tableau analytics, Grice's maxim of quality, and epistemic considerations to have the robot politely make sense of a user's sometimes unintelligible demands. Keywords: social robots, logical fallacies, metaphors, reference, sense, maxim of quality, tableau reasoning, epistemics of the virtual


Ranking Policy Gradient

arXiv.org Artificial Intelligence

Sample inefficiency is a long-lasting problem in reinforcement learning (RL). The state-of-the-art uses value function to derive policy while it usually requires an extensive search over the state-action space, which is one reason for the inefficiency. Towards the sample-efficient RL, we propose ranking policy gradient (RPG), a policy gradient method that learns the optimal ranking of a set of discrete actions. To accelerate the learning of policy gradient methods, we describe a novel off-policy learning framework and establish the equivalence between maximizing the lower bound of return and imitating a near-optimal policy without accessing any oracles. These results lead to a general sample-efficient off-policy learning framework, which accelerates learning and reduces variance. Furthermore, the sample complexity of RPG does not depend on the dimension of state space, which enables RPG for large-scale problems. We conduct extensive experiments showing that when consolidating with the off-policy learning framework, RPG substantially reduces the sample complexity, comparing to the state-of-the-art.


Sequence Generation: From Both Sides to the Middle

arXiv.org Artificial Intelligence

The encoder-decoder framework has achieved promising process for many sequence generation tasks, such as neural machine translation and text summarization. Such a framework usually generates a sequence token by token from left to right, hence (1) this autoregressive decoding procedure is time-consuming when the output sentence becomes longer, and (2) it lacks the guidance of future context which is crucial to avoid under translation. To alleviate these issues, we propose a synchronous bidirectional sequence generation (SBSG) model which predicts its outputs from both sides to the middle simultaneously. In the SBSG model, we enable the left-to-right (L2R) and right-to-left (R2L) generation to help and interact with each other by leveraging interactive bidirectional attention network. Experiments on neural machine translation (En-De, Ch-En, and En-Ro) and text summarization tasks show that the proposed model significantly speeds up decoding while improving the generation quality compared to the autoregressive Transformer.


Global Healthcare Cognitive Computing Market Report 2019 7แต—สฐ edition Top Companies, Sales, Revenue, Forecast and Detailed Analysis - Market Trends

#artificialintelligence

Healthcare Cognitive Computing market report is based on present industry situations, market demands, business strategies utilized by prominent players involved in this market along with their growth synopsis. This report has been segmented into types, applications and regions. The report also comprises major drivers boosting this market. Healthcare Cognitive Computing market worth about XX million USD in 2018 and it is expected to reach YY million USD in 2026 with a CAGR of AA% during the forecast period. Cognitive computing (CC) describes technology platforms that are based on the scientific disciplines of artificial intelligence and signal processing.


A new deepfake detection tool should keep world leaders safe--for now

#artificialintelligence

In experiments the technique was at least 92% accurate in spotting several variations of deepfakes, including face swaps and ones in which an impersonator is using a digital puppet. It was also able to deal with artifacts in the files that come from recompressing a video, which can confuse other detection techniques. The researchers plan to improve the technique by accounting for characteristics of a person's speech as well. The research, which was presented at a computer vision conference in California this week, was funded by Google and DARPA, a research wing of the Pentagon. DARPA is funding a program to devise better detection techniques.


Deep Learning for Student Competitions

#artificialintelligence

In today's post, Neha Goel is going to share an overview about how you can use MATLAB and Simulink for Developing Artificial Intelligent components in your competitions. Neha joined the team recently and focuses on deep learning and data science competitions. Also find a section in this post where Neha reveals what projects she is currently working on. Competitions and students in different application areas are adding AI components to their projects. The major areas include Autonomous Vehicle Competitions, Aerospace, Robotics, Data Science etc. Refer to link here to know about all competitions MathWorks sponsors. Artificial Intelligence (AI), Machine Learning (ML), and Deep Learning (DL) are some of the hottest topics right now.


Toward artificial intelligence that learns to write code

#artificialintelligence

Learning to code involves recognizing how to structure a program, and how to fill in every last detail correctly. No wonder it can be so frustrating. A new program-writing AI, SketchAdapt, offers a way out. Trained on tens of thousands of program examples, SketchAdapt learns how to compose short, high-level programs, while letting a second set of algorithms find the right sub-programs to fill in the details. Unlike similar approaches for automated program-writing, SketchAdapt knows when to switch from statistical pattern-matching to a less efficient, but more versatile, symbolic reasoning mode to fill in the gaps.