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Auditing and Achieving Intersectional Fairness in Classification Problems

arXiv.org Artificial Intelligence

Machine learning algorithms are extensively used to make increasingly more consequential decisions, so that achieving optimal predictive performance can no longer be the only focus. This paper explores intersectional fairness, that is fairness when intersections of multiple sensitive attributes -- such as race, age, nationality, etc. -- are considered. Previous research has mainly been focusing on fairness with respect to a single sensitive attribute, with intersectional fairness being comparatively less studied despite its critical importance for modern machine learning applications. We introduce intersectional fairness metrics by extending prior work, and provide different methodologies to audit discrimination in a given dataset or model outputs. Secondly, we develop novel post-processing techniques to mitigate any detected bias in a classification model. Our proposed methodology does not rely on any assumptions regarding the underlying model and aims at guaranteeing fairness while preserving good predictive performance. Finally, we give guidance on a practical implementation, showing how the proposed methods perform on a real-world dataset.


Keeping Your Distance: Solving Sparse Reward Tasks Using Self-Balancing Shaped Rewards

arXiv.org Artificial Intelligence

While using shaped rewards can be beneficial when solving sparse reward tasks, their successful application often requires careful engineering and is problem specific. For instance, in tasks where the agent must achieve some goal state, simple distance-to-goal reward shaping often fails, as it renders learning vulnerable to local optima. We introduce a simple and effective model-free method to learn from shaped distance-to-goal rewards on tasks where success depends on reaching a goal state. Our method introduces an auxiliary distance-based reward based on pairs of rollouts to encourage diverse exploration. This approach effectively prevents learning dynamics from stabilizing around local optima induced by the naive distance-to-goal reward shaping and enables policies to efficiently solve sparse reward tasks. Our augmented objective does not require any additional reward engineering or domain expertise to implement and converges to the original sparse objective as the agent learns to solve the task. We demonstrate that our method successfully solves a variety of hard-exploration tasks (including maze navigation and 3D construction in a Minecraft environment), where naive distance-based reward shaping otherwise fails, and intrinsic curiosity and reward relabeling strategies exhibit poor performance.


Learning to Fix Build Errors with Graph2Diff Neural Networks

arXiv.org Artificial Intelligence

Professional software developers spend a significant amount of time fixing builds, but this has received little attention as a problem in automatic program repair. We present a new deep learning architecture, called Graph2Diff, for automatically localizing and fixing build errors. We represent source code, build configuration files, and compiler diagnostic messages as a graph, and then use a Graph Neural Network model to predict a diff. A diff specifies how to modify the code's abstract syntax tree, represented in the neural network as a sequence of tokens and of pointers to code locations. Our network is an instance of a more general abstraction that we call Graph2Tocopo, which is potentially useful in any development tool for predicting source code changes. We evaluate the model on a dataset of over 500k real build errors and their resolutions from professional developers. Compared to the approach of DeepDelta (Mesbah et al., 2019), our approach tackles the harder task of predicting a more precise diff but still achieves over double the accuracy.


Compiling Arguments in an Argumentation Framework into Three-valued Logical Expressions

arXiv.org Artificial Intelligence

In this paper, we propose a new method for computing general allocators directly from completeness conditions. A general allocator is an abstraction of all complete labelings for an argumentation framework. Any complete labeling is obtained from a general allocator by assigning logical constants to variables. We proved the existence of the general allocators in our previous work. However, the construction requires us to enumerate all complete labelings for the framework, which makes the computation prohibitively slow. The method proposed in this paper enables us to compute general allocators without enumerating complete labelings. It also provides the solutions of local allocation that yield semantics for subsets of the framework. We demonstrate two applications of general allocators, stability, and a new concept for frameworks, termed arity. Moreover, the method, including local allocation, is applicable to broad extensions of frameworks, such as argumentation frameworks with set-attacks, bipolar argumentation frameworks, and abstract dialectical frameworks.


AAAI FSS-19: Artificial Intelligence in Government and Public Sector Proceedings

arXiv.org Artificial Intelligence

Proceedings of the AAAI Fall Symposium on Artificial Intelligence in Government and Public Sector, Arlington, Virginia, USA, November 7-8, 2019


Evolving Structures in Complex Systems

arXiv.org Artificial Intelligence

--In this paper we propose an approach for measuring growth of complexity of emerging patterns in complex systems such as cellular automata. We discuss several ways how a metric for measuring the complexity growth can be defined. This includes approaches based on compression algorithms and artificial neural networks. We believe such a metric can be useful for designing systems that could exhibit open-ended evolution, which itself might be a prerequisite for development of general artificial intelligence. We conduct experiments on 1D and 2D grid worlds and demonstrate that using the proposed metric we can automatically construct computational models with emerging properties similar to those found in the Conway's Game of Life, as well as many other emergent phenomena. Interestingly, some of the patterns we observe resemble forms of artificial life. Our metric of structural complexity growth can be applied to a wide range of complex systems, as it is not limited to cellular automata. Recent advances in machine learning and deep learning have had successes at reproducing some very complex feats traditionally thought to be only achievable by living beings. However, making these systems adaptable and capable of developing and evolving on their own remains a challenge that might be crucial for eventually developing AI with general learning capabilities (for example as is further discussed in [1]). Building systems that mimic some key aspects of the behavior of existing intelligent organisms (such as the ability to evolve, improve, adapt, etc.) might represent a promising path. Intelligent organisms -- e.g., human beings but also most living organisms if we consider a broad definition of intelligence -- are a form of spontaneously occurring, ever evolving complex systems that exhibit these kinds of properties [2].


Explaining the Predictions of Any Image Classifier via Decision Trees

arXiv.org Artificial Intelligence

Despite outstanding contribution to the significant progress of Artificial Intelligence (AI), deep learning models remain mostly black boxes, which are extremely weak in explainability of the reasoning process and prediction results. Explainability is not only a gateway between AI and society but also a powerful tool to detect flaws in the model and biases in the data. Local Interpretable Model-agnostic Explanation (LIME) is a recent approach that uses a linear regression model to form a local explanation for the individual prediction result. However, being so restricted and usually oversimplifying the relationships, linear models fail in situations where nonlinear associations and interactions exist among features and prediction results. This paper proposes an extended Decision Tree-based LIME (TLIME) approach, which uses a decision tree model to form an interpretable representation that is locally faithful to the original model. The new approach can capture nonlinear interactions among features in the data and creates plausible explanations. Various experiments show that the TLIME explanation of multiple blackbox models can achieve more reliable performance in terms of understandability, fidelity, and efficiency.


Join Us: Machine Learning & Artificial Intelligence For The Federal Government DataRobot

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November 21, 2019 Artificial intelligence (AI) is emerging as the prize in an increasingly competitive geopolitical environment, with American rivals investing in AI to shift the military, political, and economic balance of power against the U.S. Leveraging AI can help make the government more efficient, spurring economic growth, and transforming education for future generations. Yet agency leaders still search for where to begin within their own departments. What projects will be the most impactful? What can be done to train the existing workforce to leverage the power of AI? What to expect: You will leave this course able to identify top AI opportunities, with an understanding of key AI success factors, and with a clearly defined project ready for your team to execute. Who should attend: Agency leaders seeking to initiate or improve the performance of machine learning initiatives and AI projects for their agency or department.


Artificial Intelligence on Wall Street Will Be Great, Until It Isn't

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Until recently, artificial intelligence has struggled to gain a foothold on Wall Street. In the last few years, large investment banks like Goldman Sachs and JP Morgan have hired artificial intelligence specialists away from academia and put them in charge of their internal AI divisions. Financial technology start-ups have begun using machine-learning algorithms to model credit ratings and detect fraud. And hedge funds and high-frequency traders are using AI to make investment decisions. Politicians are starting to take notice.


AI Black Box Horror Stories -- When Transparency was Needed More Than Ever

#artificialintelligence

Arguably, one of the biggest debates happening in data science in 2019 is the need for AI explainability. The ability to interpret machine learning models is turning out to be a defining factor for the acceptance of statistical models for driving business decisions. Enterprise stakeholders are demanding transparency in how and why these algorithms are making specific predictions. A firm understanding of any inherent bias in machine learning keeps boiling up to the top of requirements for data science teams. As a result, many top vendors in the big data ecosystem are launching new tools to take a stab at resolving the challenge of opening the AI "black box." Some organizations have taken the plunge into AI even with the realization that their algorithm's decisions can't be explained.