Oceania
Resource Aware Multifidelity Active Learning for Efficient Optimization
Grassi, Francesco, Manganini, Giorgio, Garraffa, Michele, Mainini, Laura
Traditional methods for black box optimization require a considerable number of evaluations which can be time consuming, unpractical, and often unfeasible for many engineering applications that rely on accurate representations and expensive models to evaluate. Bayesian Optimization (BO) methods search for the global optimum by progressively (actively) learning a surrogate model of the objective function along the search path. Bayesian optimization can be accelerated through multifidelity approaches which leverage multiple black-box approximations of the objective functions that can be computationally cheaper to evaluate, but still provide relevant information to the search task. Further computational benefits are offered by the availability of parallel and distributed computing architectures whose optimal usage is an open opportunity within the context of active learning. This paper introduces the Resource Aware Active Learning (RAAL) strategy, a multifidelity Bayesian scheme to accelerate the optimization of black box functions. At each optimization step, the RAAL procedure computes the set of best sample locations and the associated fidelity sources that maximize the information gain to acquire during the parallel/distributed evaluation of the objective function, while accounting for the limited computational budget. The scheme is demonstrated for a variety of benchmark problems and results are discussed for both single fidelity and multifidelity settings. In particular we observe that the RAAL strategy optimally seeds multiple points at each iteration allowing for a major speed up of the optimization task.
Could this wearable device be the answer to workplace social distancing?
With numerous organisations rapidly adapting to the use of new technologies within and outside of the workplace, wearable devices could soon become a common sight in offices as a means of enforcing workplace social distancing. Many are still working from home, but for those unable to carry out their jobs remotely, or those who have chosen to return to the workplace, ensuring they can do so safely is of paramount importance. The UK government has advised businesses to carry out a Covid-19 risk assessment, develop hygiene procedures, maintain workplace social distancing and manage transmission risk. But applying this to a busy workplace where employees attend meetings, collaborate on projects or simply socialise within the workplace makes keeping two metres apart a challenge. With this in mind, robotics company Tharsus has come up with a technology-based solution to "get businesses working again". The company, which has already developed technology solutions for companies such as DHL, Ocado, Rolls Royce, Automata and Small Robot Co, has developed "Bump", a Fitbit-style personal motion system designed to be a "simple, intuitive and friendly" way of improving workplace safety during the pandemic.
Can AI Answer "What's the Meaning Of Life"? - Analytics India Magazine
With artificial intelligence maturing in the current era, it is gaining immense potential in becoming a key technology for practical applications. Although the technology has displayed expertise in coming up with answers to business queries with accuracy, it often struggles to answer questions that are abstract in nature. In fact, even these conversation AI bots like Alexa and Siri are advanced in managing our schedule but if asked obscure existential questions like "meaning of life," it will only provide you with either a hilarious response or a sarcastic joke. However, as artificial intelligence is evolving with advancements in natural language processing, speech recognition and automated reasoning, the technology can now answer some of the tough life questions asked by humans. To test the theory, researchers from the University of New South Wales asked some moral and existential questions to Salesforce's Conditional Transformer Language model to check if the AI is capable of answering some fundamental questions of life.
Singapore, in survival mode, looks to reinvent itself. Yet again.
The pandemic is proving to be the ultimate test for Singapore, the tiny city-state that has a reputation for reinventing itself during times of crises. Dismissed in the past as just a "little red dot" on the map, dwarfed by larger neighbors like Malaysia and Indonesia, and with no natural resources to speak of, Singapore has nonetheless transformed itself into one of the richest and most competitive economies in the world. As Singapore's leaders now grapple with what's turning out to be its worst slump since independence in 1965, the ruling party is looking to extend its mandate in Friday's election to help reinvent the economy once again. They're already positioning for a post-COVID-19 world with planned investment in health and biomedical sciences, climate change and artificial intelligence. Crises have been a catalyst for change in the past.
Decolonial AI: Decolonial Theory as Sociotechnical Foresight in Artificial Intelligence
Mohamed, Shakir, Png, Marie-Therese, Isaac, William
This paper explores the important role of critical science, and in particular of post-colonial and decolonial theories, in understanding and shaping the ongoing advances in artificial intelligence. Artificial Intelligence (AI) is viewed as amongst the technological advances that will reshape modern societies and their relations. Whilst the design and deployment of systems that continually adapt holds the promise of far-reaching positive change, they simultaneously pose significant risks, especially to already vulnerable peoples. Values and power are central to this discussion. Decolonial theories use historical hindsight to explain patterns of power that shape our intellectual, political, economic, and social world. By embedding a decolonial critical approach within its technical practice, AI communities can develop foresight and tactics that can better align research and technology development with established ethical principles, centring vulnerable peoples who continue to bear the brunt of negative impacts of innovation and scientific progress. We highlight problematic applications that are instances of coloniality, and using a decolonial lens, submit three tactics that can form a decolonial field of artificial intelligence: creating a critical technical practice of AI, seeking reverse tutelage and reverse pedagogies, and the renewal of affective and political communities. The years ahead will usher in a wave of new scientific breakthroughs and technologies driven by AI research, making it incumbent upon AI communities to strengthen the social contract through ethical foresight and the multiplicity of intellectual perspectives available to us; ultimately supporting future technologies that enable greater well-being, with the goal of beneficence and justice for all.
COVID-ABS: An Agent-Based Model of COVID-19 Epidemic to Simulate Health and Economic Effects of Social Distancing Interventions
Silva, Petrônio C. L., Batista, Paulo V. C., Lima, Hélder S., Alves, Marcos A., Guimarães, Frederico G., Silva, Rodrigo C. P.
The COVID-19 pandemic due to the SARS-CoV-2 coronavirus has directly impacted the public health and economy worldwide. To overcome this problem, countries have adopted different policies and non-pharmaceutical interventions for controlling the spread of the virus. This paper proposes the COVID-ABS, a new SEIR (Susceptible-Exposed-Infected-Recovered) agent-based model that aims to simulate the pandemic dynamics using a society of agents emulating people, business and government. Seven different scenarios of social distancing interventions were analyzed, with varying epidemiological and economic effects: (1) do nothing, (2) lockdown, (3) conditional lockdown, (4) vertical isolation, (5) partial isolation, (6) use of face masks, and (7) use of face masks together with 50% of adhesion to social isolation. In the impossibility of implementing scenarios with lockdown, which present the lowest number of deaths and highest impact on the economy, scenarios combining the use of face masks and partial isolation can be the more realistic for implementation in terms of social cooperation. The COVID-ABS model was implemented in Python programming language, with source code publicly available. The model can be easily extended to other societies by changing the input parameters, as well as allowing the creation of a multitude of other scenarios. Therefore, it is a useful tool to assist politicians and health authorities to plan their actions against the COVID-19 epidemic.
Diverse Ensembles Improve Calibration
Stickland, Asa Cooper, Murray, Iain
Modern deep neural networks can produce badly calibrated predictions, especially when train and test distributions are mismatched. Training an ensemble of models and averaging their predictions can help alleviate these issues. We propose a simple technique to improve calibration, using a different data augmentation for each ensemble member. We additionally use the idea of `mixing' un-augmented and augmented inputs to improve calibration when test and training distributions are the same. These simple techniques improve calibration and accuracy over strong baselines on the CIFAR10 and CIFAR100 benchmarks, and out-of-domain data from their corrupted versions.
Model-based Clustering using Automatic Differentiation: Confronting Misspecification and High-Dimensional Data
Kasa, Siva Rajesh, Rajan, Vaibhav
We study two practically important cases of model based clustering using Gaussian Mixture Models: (1) when there is misspecification and (2) on high dimensional data, in the light of recent advances in Gradient Descent (GD) based optimization using Automatic Differentiation (AD). Our simulation studies show that EM has better clustering performance, measured by Adjusted Rand Index, compared to GD in cases of misspecification, whereas on high dimensional data GD outperforms EM. We observe that both with EM and GD there are many solutions with high likelihood but poor cluster interpretation. To address this problem we design a new penalty term for the likelihood based on the Kullback Leibler divergence between pairs of fitted components. Closed form expressions for the gradients of this penalized likelihood are difficult to derive but AD can be done effortlessly, illustrating the advantage of AD-based optimization. Extensions of this penalty for high dimensional data and for model selection are discussed. Numerical experiments on synthetic and real datasets demonstrate the efficacy of clustering using the proposed penalized likelihood approach.
Transparency Tools for Fairness in AI (Luskin)
Chen, Mingliang, Shahverdi, Aria, Anderson, Sarah, Park, Se Yong, Zhang, Justin, Dachman-Soled, Dana, Lauter, Kristin, Wu, Min
We propose new tools for policy-makers to use when assessing and correcting fairness and bias in AI algorithms. The three tools are: - A new definition of fairness called "controlled fairness" with respect to choices of protected features and filters. The definition provides a simple test of fairness of an algorithm with respect to a dataset. This notion of fairness is suitable in cases where fairness is prioritized over accuracy, such as in cases where there is no "ground truth" data, only data labeled with past decisions (which may have been biased). - Algorithms for retraining a given classifier to achieve "controlled fairness" with respect to a choice of features and filters. Two algorithms are presented, implemented and tested. These algorithms require training two different models in two stages. We experiment with combinations of various types of models for the first and second stage and report on which combinations perform best in terms of fairness and accuracy. - Algorithms for adjusting model parameters to achieve a notion of fairness called "classification parity". This notion of fairness is suitable in cases where accuracy is prioritized. Two algorithms are presented, one which assumes that protected features are accessible to the model during testing, and one which assumes protected features are not accessible during testing. We evaluate our tools on three different publicly available datasets. We find that the tools are useful for understanding various dimensions of bias, and that in practice the algorithms are effective in starkly reducing a given observed bias when tested on new data.
Online probabilistic label trees
Jasinska-Kobus, Kalina, Wydmuch, Marek, Thiruvenkatachari, Devanathan, Dembczyński, Krzysztof
We introduce online probabilistic label trees (OPLTs), an algorithm that trains a label tree classifier in a fully online manner, without any prior knowledge about the number of training instances, their features and labels. OPLTs are characterized by low time and space complexity as well as strong theoretical guarantees. They can be used for online multi-label and multi-class classification, including the very challenging scenarios of one- or few-shot learning. We demonstrate the attractiveness of OPLTs in a wide empirical study on several instances of the tasks mentioned above.