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Challenges and Opportunities in Quantum Machine Learning

arXiv.org Artificial Intelligence

Quantum computing exploits entanglement, superposition, and interference to perform certain tasks with significant speedups over classical computing, The recognition that the world is quantum mechanical sometimes even exponentially faster. Indeed while such has allowed researchers to embed well-established, but speedup has already been observed for a contrived problem classical, theories into the framework of quantum Hilbert [7], reaching it for data science is still uncertain even spaces. Shannon's information theory, which is the basis at the theoretical level, but this is one of the main goals of communication technology, has been generalized for QML. to quantum Shannon theory (or quantum information theory), opening up the possibility that quantum effects In practice, QML is a broad term that encompasses all could make information transmission more efficient [1]. of the tasks shown in Figure 1. For example, one can apply The field of biology has been extended to quantum biology machine learning to quantum applications like discovering to allow for a deeper understanding of biological quantum algorithms [8] or optimizing quantum experiments processes like photosynthesis, smell, and enzyme catalysis [9, 10], or one can use a quantum neural network [2]. Turing's theory of universal computation has been to process either classical or quantum information [11].


Machine learning based biomedical image processing for echocardiographic images

arXiv.org Artificial Intelligence

The popularity of Artificial intelligence and machine learning have prompted researchers to use it in the recent researches. The proposed method uses K-Nearest Neighbor (KNN) algorithm for segmentation of medical images, extracting of image features for analysis by classifying the data based on the neural networks. Classification of the images in medical imaging is very important, KNN is one suitable algorithm which is simple, conceptual and computational, which provides very good accuracy in results. KNN algorithm is a unique user-friendly approach with wide range of applications in machine learning algorithms which are majorly used for the various image processing applications including classification, segmentation and regression issues of the image processing. The proposed system uses gray level co-occurrence matrix features. The trained neural network has been tested successfully on a group of echocardiographic images, errors were compared using regression plot. The results of the algorithm are tested using various quantitative as well as qualitative metrics and proven to exhibit better performance in terms of both quantitative and qualitative metrics in terms of current state -of-the-art methods in the related area. To compare the performance of trained neural network the regression analysis performed showed a good correlation.


Human-AI Collaboration: The Effect of AI Delegation on Human Task Performance and Task Satisfaction

arXiv.org Artificial Intelligence

Recent work has proposed artificial intelligence (AI) models that can learn to decide whether to make a prediction for an instance of a task or to delegate it to a human by considering both parties' capabilities. In simulations with synthetically generated or context-independent human predictions, delegation can help improve the performance of human-AI teams -- compared to humans or the AI model completing the task alone. However, so far, it remains unclear how humans perform and how they perceive the task when they are aware that an AI model delegated task instances to them. In an experimental study with 196 participants, we show that task performance and task satisfaction improve through AI delegation, regardless of whether humans are aware of the delegation. Additionally, we identify humans' increased levels of self-efficacy as the underlying mechanism for these improvements in performance and satisfaction. Our findings provide initial evidence that allowing AI models to take over more management responsibilities can be an effective form of human-AI collaboration in workplaces.


Optimizing Orthogonalized Tensor Deflation via Random Tensor Theory

arXiv.org Machine Learning

This paper tackles the problem of recovering a low-rank signal tensor with possibly correlated components from a random noisy tensor, or so-called spiked tensor model. When the underlying components are orthogonal, they can be recovered efficiently using tensor deflation which consists of successive rank-one approximations, while non-orthogonal components may alter the tensor deflation mechanism, thereby preventing efficient recovery. Relying on recently developed random tensor tools, this paper deals precisely with the non-orthogonal case by deriving an asymptotic analysis of a parameterized deflation procedure performed on an order-three and rank-two spiked tensor. Based on this analysis, an efficient tensor deflation algorithm is proposed by optimizing the parameter introduced in the deflation mechanism, which in turn is proven to be optimal by construction for the studied tensor model. The same ideas could be extended to more general low-rank tensor models, e.g., higher ranks and orders, leading to more efficient tensor methods with a broader impact on machine learning and beyond.


Inadmissibility of the corrected Akaike information criterion

arXiv.org Machine Learning

For the multivariate linear regression model with unknown covariance, the corrected Akaike information criterion is the minimum variance unbiased estimator of the expected Kullback--Leibler discrepancy. In this study, based on the loss estimation framework, we show its inadmissibility as an estimator of the Kullback--Leibler discrepancy itself, instead of the expected Kullback--Leibler discrepancy. We provide improved estimators of the Kullback--Leibler discrepancy that work well in reduced-rank situations and examine their performance numerically.


Natural Language Processing Methods to Identify Oncology Patients at High Risk for Acute Care with Clinical Notes

arXiv.org Artificial Intelligence

Clinical notes are an essential component of a health record. This paper evaluates how natural language processing (NLP) can be used to identify the risk of acute care use (ACU) in oncology patients, once chemotherapy starts. Risk prediction using structured health data (SHD) is now standard, but predictions using free-text formats are complex. This paper explores the use of free-text notes for the prediction of ACU instead of SHD. Deep Learning models were compared to manually engineered language features. Results show that SHD models minimally outperform NLP models; an l1-penalised logistic regression with SHD achieved a C-statistic of 0.748 (95%-CI: 0.735, 0.762), while the same model with language features achieved 0.730 (95%-CI: 0.717, 0.745) and a transformer-based model achieved 0.702 (95%-CI: 0.688, 0.717). This paper shows how language models can be used in clinical applications and underlines how risk bias is different for diverse patient groups, even using only free-text data.


Finding Minimum-Cost Explanations for Predictions made by Tree Ensembles

arXiv.org Artificial Intelligence

The ability to explain why a machine learning model arrives at a particular prediction is crucial when used as decision support by human operators of critical systems. The provided explanations must be provably correct, and preferably without redundant information, called minimal explanations. In this paper, we aim at finding explanations for predictions made by tree ensembles that are not only minimal, but also minimum with respect to a cost function. To this end, we first present a highly efficient oracle that can determine the correctness of explanations, surpassing the runtime performance of current state-of-the-art alternatives by several orders of magnitude when computing minimal explanations. Secondly, we adapt an algorithm called MARCO from related works (calling it m-MARCO) for the purpose of computing a single minimum explanation per prediction, and demonstrate an overall speedup factor of two compared to the MARCO algorithm which enumerates all minimal explanations. Finally, we study the obtained explanations from a range of use cases, leading to further insights of their characteristics. In particular, we observe that in several cases, there are more than 100,000 minimal explanations to choose from for a single prediction. In these cases, we see that only a small portion of the minimal explanations are also minimum, and that the minimum explanations are significantly less verbose, hence motivating the aim of this work.


Progress in Nonsmooth Optimization part4(Machine Learning)

#artificialintelligence

Abstract:: We propose and analyze several stochastic gradient algorithms for finding stationary points or local minimum in nonconvex, possibly with nonsmooth regularizer, finite-sum and online optimization problems. First, we propose a simple proximal stochastic gradient algorithm based on variance reduction called ProxSVRG . We provide a clean and tight analysis of ProxSVRG, which shows that it outperforms the deterministic proximal gradient descent (ProxGD) for a wide range of minibatch sizes, hence solves an open problem proposed in Reddi et al. (2016b). Also, ProxSVRG uses much less proximal oracle calls than ProxSVRG (Reddi et al., 2016b) and extends to the online setting by avoiding full gradient computations. Then, we further propose an optimal algorithm, called SSRGD, based on SARAH (Nguyen et al., 2017) and show that SSRGD further improves the gradient complexity of ProxSVRG and achieves the optimal upper bound, matching the known lower bound of (Fang et al., 2018; Li et al., 2021).


Interpretable Ensembles of Hyper-Rectangles as Base Models

arXiv.org Artificial Intelligence

A new extremely simple ensemble-based model with the uniformly generated axis-parallel hyper-rectangles as base models (HRBM) is proposed. Two types of HRBMs are studied: closed rectangles and corners. The main idea behind HRBM is to consider and count training examples inside and outside each rectangle. It is proposed to incorporate HRBMs into the gradient boosting machine (GBM). Despite simplicity of HRBMs, it turns out that these simple base models allow us to construct effective ensemble-based models and avoid overfitting. A simple method for calculating optimal regularization parameters of the ensemble-based model, which can be modified in the explicit way at each iteration of GBM, is considered. Moreover, a new regularization called the "step height penalty" is studied in addition to the standard L1 and L2 regularizations. An extremely simple approach to the proposed ensemble-based model prediction interpretation by using the well-known method SHAP is proposed. It is shown that GBM with HRBM can be regarded as a model extending a set of interpretable models for explaining black-box models. Numerical experiments with real datasets illustrate the proposed GBM with HRBMs for regression and classification problems. Experiments also illustrate computational efficiency of the proposed SHAP modifications. The code of proposed algorithms implementing GBM with HRBM is publicly available.


Machine Learning-Driven Adaptive OpenMP For Portable Performance on Heterogeneous Systems

arXiv.org Artificial Intelligence

The end of Dennard scaling law -- which stipulated a continuous increase in processor clock frequency by transistor miniaturization -- in conjunction with the continuation of Moore's law -- which expects the number of CMOS transistors within a microchip to double every two years -- shifted the technology trend towards parallel architectures. In the early 2000's parallel computer system architectures focused on multi-core CPU architectures. Later the introduction of the GPGPU paradigms pivoted technology trends to heterogeneous systems composed of both multi-core CPUs and GPUs. This heterogeneity unveiled the challenge of software performance portability. Software performance portability seeks to achieve equivalent performance regardless of the underlying hardware architecture using a single application implementation. Programming models, such as OmpSs [9], OpenMP, Kokkos [10], and RAJA [15], provide abstractions to hide the vendor-specific interfaces required to develop applications on all these heterogeneous parallel architectures and offer unified interfaces to express parallelism. Although these programming models provide a single and convenient layer to implement portable code, the performance of the same application can vary when executed on different architectures and systems. Thus, these programming models efficiently express portable code, but the application performance-portability is unspecified for application executions on different heterogeneous systems. For example, HPC programmers have found that a single version of source code, with an associated static definition of exarXiv:2303.08873v1