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Top 10 Machine Learning Algorithms Explained

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Linear Regression: For statistical techniques, linear regression is used in which the value of the dependent variable is predicted through independent variables. A relationship is formed by mapping the dependent and independent variable on a line, and that line is called the regression line, which is represented by Y a*X b where Y Dependent variable (for example, weight) X Independent Variable (e.g., height) b Intercept and a slope. Logistic Regression: In logistic regression, we have a lot of data whose classification is done by building an equation. This method is used to find the discrete dependent variable from the set of independent variables. Its goal is to find the best fit set of parameters. In this classifier, each feature is multiplied by a weight, and then all are added.


Breaking it Down: Gradient Descent

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Originally published on Towards AI the World's Leading AI and Technology News and Media Company. If you are building an AI-related product or service, we invite you to consider becoming an AI sponsor. At Towards AI, we help scale AI and technology startups. Let us help you unleash your technology to the masses. Gradient descent is an optimization algorithm that is used to improve the performance of deep/machine learning models.


Logistic Regression

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The outcome of a Linear Regression can take any form, discrete or continuous, and it may not be limited, within a boundary, in range 0 to 1. Linear Regression can give values large than 1 or less than 0 which is not desirable for classification problem. Logistic Regression, on the other hand, as we have seen above squeezes the output between 0 and 1 which is more desirable for classification problem. Linear Regression is based on linear algebra where as Logistic Regression uses probability.


Comprehensive Guide to Model Selection

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To help navigate the abundant options for creating a machine learning model, we recommend a five step process that results in a useful data product. We recommend starting off with Human Centered Design-empowered approach. HCD focuses on the challenges faced by the end user and uses a framework to make decisions up-front that will guide the remainder of the model selection process. This helps keep the data scientist working toward resolving the business problem -- not getting mired in technical difficulties. With the learnings from the HCD phase in mind, the data scientist next conducts a survey of the landscape of models that could tackle the business challenge.


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Signal Processing Society Magazine Best Paper Award (ICASSPใซใฆ) A. Cichocki (Skoltech) L. De Lathauwer (KULeuven) 19 ใƒ†ใƒณใ‚ฝใƒซๅˆ†่งฃใฎใƒ‘ใ‚คใ‚ชใƒ‹ใ‚ขใจ้‡่ฆใชๆ–‡็Œฎ Sidiropoulosใ‚‰ใฎใƒฌใƒ“ใƒฅใƒผ่ซ–ๆ–‡ Tensor Decomposition for Signal Processing and Machine Learning Sidiropoulos, IEEE TSP, 2017 [pdf] Cichockiใ‚‰ใฎๆ›ธ็ฑ Tensor Networks for Dimensionality Reduction and Large-Scale Optimization: Part 1 [link], Part 2 [pdf] Cichocki, Foundations and Trends in Machine Learning, 2016 [link] N. Sidiropoulos (Univ. of Virginia) 20 ๅฎฃไผ Book chapterใ‚’ๆ›ธใใพใ—ใŸ Tensors for Data Processing, Elsevier, 2021 [link] ็›ฎๆฌก 1็ซ  Tensor decompositions: Computations, applications, and challenges 2็ซ  Transform-based tensor SVD in multidimensional image recovery 3็ซ  Partensor 4็ซ  A Riemannian approach to low-rank tensor learning 5็ซ  Generalized thresholding for low-rank tensor recovery 6็ซ  Tensor principal component analysis 7็ซ  Tensors for deep learning theory 8็ซ  Tensor network algorithms for image classification 9็ซ  High-performance TD for compressing and accelerating DNN 10็ซ  Coupled tensor decomposition for data fusion 11็ซ  Tensor methods for low-level vision T. Yokota, CF.


Understanding Neural Networks -- Part 1/3: Intuition of Forward Propagation

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Basically, it's just a type of ML algorithm that was built to emulate connections in a brain. It can be used for classification and regression tasks. Today, we're going to go over a classification task. The big thing about NNs is that they are "universal function approximators," meaning they can approximate any function (duh). Compare this with linear regression which ONLY can approximate linear functions. The first layer is called the input layer and has as many neurons as we have features in our data.


SHAP for additively modeled features in a boosted trees model

arXiv.org Artificial Intelligence

An important technique to explore a black-box machine learning (ML) model is called SHAP (SHapley Additive exPlanation). SHAP values decompose predictions into contributions of the features in a fair way. We will show that for a boosted trees model with some or all features being additively modeled, the SHAP dependence plot of such a feature corresponds to its partial dependence plot up to a vertical shift. We illustrate the result with XGBoost.


Enhanced gradient-based MCMC in discrete spaces

arXiv.org Artificial Intelligence

The recent introduction of gradient-based MCMC for discrete spaces holds great promise, and comes with the tantalising possibility of new discrete counterparts to celebrated continuous methods such as MALA and HMC. Towards this goal, we introduce several discrete Metropolis-Hastings samplers that are conceptually-inspired by MALA, and demonstrate their strong empirical performance across a range of challenging sampling problems in Bayesian inference and energy-based modelling. Methodologically, we identify why discrete analogues to preconditioned MALA are generally intractable, motivating us to introduce a new kind of preconditioning based on auxiliary variables and the `Gaussian integral trick'.


Differentially Private SGDA for Minimax Problems

arXiv.org Artificial Intelligence

Stochastic gradient descent ascent (SGDA) and its variants have been the workhorse for solving minimax problems. However, in contrast to the well-studied stochastic gradient descent (SGD) with differential privacy (DP) constraints, there is little work on understanding the generalization (utility) of SGDA with DP constraints. In this paper, we use the algorithmic stability approach to establish the generalization (utility) of DP-SGDA in different settings. In particular, for the convex-concave setting, we prove that the DP-SGDA can achieve an optimal utility rate in terms of the weak primal-dual population risk in both smooth and non-smooth cases. To our best knowledge, this is the first-ever-known result for DP-SGDA in the non-smooth case. We further provide its utility analysis in the nonconvex-strongly-concave setting which is the first-ever-known result in terms of the primal population risk. The convergence and generalization results for this nonconvex setting are new even in the non-private setting. Finally, numerical experiments are conducted to demonstrate the effectiveness of DP-SGDA for both convex and nonconvex cases.


A Learned Index for Exact Similarity Search in Metric Spaces

arXiv.org Artificial Intelligence

Indexing is an effective way to support efficient query processing in large databases. Recently the concept of learned index, which replaces or complements traditional index structures with machine learning models, has been actively explored to reduce storage and search costs. However, accurate and efficient similarity query processing in high-dimensional metric spaces remains to be an open challenge. In this paper, we propose a novel indexing approach called LIMS that uses data clustering, pivot-based data transformation techniques and learned indexes to support efficient similarity query processing in metric spaces. In LIMS, the underlying data is partitioned into clusters such that each cluster follows a relatively uniform data distribution. Data redistribution is achieved by utilizing a small number of pivots for each cluster. Similar data are mapped into compact regions and the mapped values are totally ordinal. Machine learning models are developed to approximate the position of each data record on disk. Efficient algorithms are designed for processing range queries and nearest neighbor queries based on LIMS, and for index maintenance with dynamic updates. Extensive experiments on real-world and synthetic datasets demonstrate the superiority of LIMS compared with traditional indexes and state-of-the-art learned indexes.