California Institute of Technology
Online Learning and Profit Maximization from Revealed Preferences
Amin, Kareem (University of Pennsylvania) | Cummings, Rachel (California Institute of Technology) | Dworkin, Lili (University of Pennsylvania) | Kearns, Michael (University of Pennsylvania) | Roth, Aaron (University of Pennsylvania)
We consider the problem of learning from revealed preferences in an online setting. In our framework, each period a consumer buys an optimal bundle of goods from a merchant according to her (linear) utility function and current prices, subject to a budget constraint. The merchant observes only the purchased goods, and seeks to adapt prices to optimize his profits. We give an efficient algorithm for the merchant's problem that consists of a learning phase in which the consumer's utility function is (perhaps partially) inferred, followed by a price optimization step. We also give an alternative online learning algorithm for the setting where prices are set exogenously, but the merchant would still like to predict the bundle that will be bought by the consumer, for purposes of inventory or supply chain management. In contrast with most prior work on the revealed preferences problem, we demonstrate that by making stronger assumptions on the form of utility functions, efficient algorithms for both learning and profit maximization are possible, even in adaptive, online settings.
Pattern Decomposition with Complex Combinatorial Constraints: Application to Materials Discovery
Ermon, Stefano (Stanford University) | Bras, Ronan Le (Cornell University) | Suram, Santosh K. (California Institute of Technology) | Gregoire, John M. (California Institute of Technology) | Gomes, Carla P. (Cornell University) | Selman, Bart (Cornell University) | Dover, Robert B. van (Cornell University)
Identifying important components or factors in large amounts of noisy data is a key problem in machine learning and data mining. Motivated by a pattern decomposition problem in materials discovery, aimed at discovering new materials for renewable energy, e.g. for fuel and solar cells, we introduce CombiFD, a framework for factor based pattern decomposition that allows the incorporation of a-priori knowledge as constraints, including complex combinatorial constraints. In addition, we propose a new pattern decomposition algorithm, called AMIQO, based on solving a sequence of (mixed-integer) quadratic programs. Our approach considerably outperforms the state of the art on the materials discovery problem, scaling to larger datasets and recovering more precise and physically meaningful decompositions. We also show the effectiveness of our approach for enforcing background knowledge on other application domains.
Mixed-Integer Linear Programming for Planning with Temporal Logic Tasks [Position Paper]
Raman, Vasumathi (California Institute of Technology) | Wolff, Eric M. (nuTonomy LLC)
We are concerned with controlling dynamical systems, such as self-driving cars and smart buildings, in a manner that guarantees that they satisfy complex task specifications. Mixed integer linear programming has recently proven to be a powerful tool for such problems, enabling the computation of optimal plans that satisfy complex temporal constraints for high-dimensional, dynamical systems. These optimization-based approaches find solutions quickly for challenging (and previously unsolvable) planning problems. Framing temporal logic planning as constrained optimization also presents exciting new areas of research.
Challenges in Materials Discovery – Synthetic Generator and Real Datasets
Bras, Ronan Le (Cornell University) | Bernstein, Richard (Cornell University) | Gregoire, John M (California Institute of Technology) | Suram, Santosh K (California Institute of Technology) | Gomes, Carla P (Cornell University) | Selman, Bart (Cornell University) | Dover, R. Bruce van (Cornell University)
Newly-discovered materials have been central to recent technological advances. They have contributed significantly to breakthroughs in electronics, renewable energy and green buildings, and overall, have promoted the advancement of global human welfare. Yet, only a fraction of all possible materials have been explored. Accelerating the pace of discovery of materials would foster technological innovations, and would potentially address pressing issues in sustainability, such as energy production or consumption. The bottleneck of this discovery cycle lies, however, in the analysis of the materials data. As materials scientists have recently devised techniques to efficiently create thousands of materials and experimentalists have developed new methods and tools to characterize these materials, the limiting factor has become the data analysis itself. Hence, the goal of this paper is to stimulate the development of new computational techniques for the analysis of materials data, by bringing together the complimentary expertise of materials scientists and computer scientists. In collaboration with two major research laboratories in materials science, we provide the first publicly available dataset for the phase map identification problem. In addition, we provide a parameterized synthetic data generator to assess the quality of proposed approaches, as well as tools for data visualization and solution evaluation.
Mendacity and Deception: Uses and Abuses of Common Ground
Clark, Micah Henry (California Institute of Technology)
The concept of common ground — the mutual understanding of context and conventions — is central to philosophical accounts of mendacity; its use is to determine the meaning of linguistic expressions and the significance of physical acts, and to distinguish certain statements as conveying a conventional promise, warranty, or expectation of sincerity. Lying necessarily involves an abuse of common ground, namely the willful violation of conventions regulating sincerity. The ‘lying machine’ is an AI system that purposely abuses common ground as an effective means for practicing mendacity and lesser deceptions. The machine's method is to conceive and articulate sophisms — perversions of normative reason and communication — crafted to subvert its audience's beliefs. Elements of this paper (i) explain the described use of common ground in philosophical accounts of mendacity, (ii) motivate arguments and illusions as stratagem for deception, (iii) encapsulate the lying machine's design and operation, and (iv) summarize human-subject experiments that confirm the lying machine's arguments are, in fact, deceptive.
Automatic Synthesis of Robust Embedded Control Software
Wongpiromsarn, Tichakorn (California Institute of Technology) | Topcu, Ufuk (California Institute of Technology) | Murray, Richard M. (California Institute of Technology)
We propose a methodology for automatic synthesis of embedded control software that accounts for exogenous disturbances. The resulting system is guaranteed, by construction, to satisfy a given specification expressed in linear temporal logic. The embedded control software consists of three components: a goal generator, a trajectory planner, and a continuous controller. We demonstrate the effectiveness of the proposed technique through an example of an autonomous vehicle navigating an urban environment. This example also illustrates that the system is not only robust with respect to exogenous disturbances but also capable of handling violation of the environment assumptions.