Statistical Learning
A Case for Quantifying Statistical Robustness of Specialized Probabilistic AI Accelerators
Zhang, Xiangyu, Mukherjee, Sayan, Lebeck, Alvin R.
Statistical machine learning often uses probabilistic algorithms, such as Markov Chain Monte Carlo (MCMC), to solve a wide range of problems. Many accelerators are proposed using specialized hardware to address sampling inefficiency, the critical performance bottleneck of probabilistic algorithms. These accelerators usually improve the hardware efficiency by using some approximation techniques, such as reducing bit representation, truncating small values to zero, or simplifying the Random Number Generator (RNG). Understanding the influence of these approximations on result quality is crucial to meeting the quality requirements of real applications. Although a common approach is to compare the end-point result quality using community-standard benchmarks and metrics, we claim a probabilistic architecture should provide some measure (or guarantee) of statistical robustness. This work takes a first step towards quantifying the statistical robustness of specialized hardware MCMC accelerators by proposing three pillars of statistical robustness: sampling quality, convergence diagnostic, and goodness of fit. Each pillar has at least one quantitative metric without the need to know the ground truth data. We apply this method to analyze the statistical robustness of an MCMC accelerator proposed by previous work, with some modifications, as a case study. The method also applies to other probabilistic accelerators and can be used in design space exploration.
Data Science for Marketing Analytics
Data Science for Marketing Analytics: Achieve your marketing goals with the data analytics power of Python Explore new and more sophisticated tools that reduce your marketing analytics efforts and give you precise results Key Features Study new techniques for marketing analytics Explore uses of machine learning to power your marketing analyses Work through each stage of data analytics with the help of multiple examples and exercises Book Description Data Science for Marketing Analytics covers every stage of data analytics, from working with a raw dataset to segmenting a population and modeling different parts of the population based on the segments. The book starts by teaching you how to use Python libraries, such as pandas and Matplotlib, to read data from Python, manipulate it, and create plots, using both categorical and continuous variables. Then, you'll learn how to segment a population into groups and use different clustering techniques to evaluate customer segmentation. As you make your way through the chapters, you'll explore ways to evaluate and select the best segmentation approach, and go on to create a linear regression model on customer value data to predict lifetime value. In the concluding chapters, you'll gain an understanding of regression techniques and tools for evaluating regression models, and explore ways to predict customer choice using classification algorithms. Finally, you'll apply these techniques to create a churn model for modeling customer product choices.
Feature Selection: Beyond feature importance? - KDnuggets
In machine learning, Feature Selection is the process of choosing features that are most useful for your prediction. Although it sounds simple it is one of the most complex problems in the work of creating a new machine learning model. In this post, I will share with you some of the approaches that were researched during the last project I led at Fiverr. You will get some ideas on the basic method I tried and also the more complex approach, which got the best results -- removing over 60% of the features, while maintaining accuracy and achieving more stability for our model. I'll also be sharing our improvement to this algorithm.
A Gentle Introduction to Cross-Entropy for Machine Learning
Cross-entropy is commonly used in machine learning as a loss function. Cross-entropy is a measure from the field of information theory, building upon entropy and generally calculating the difference between two probability distributions. It is closely related to but is different from KL divergence that calculates the relative entropy between two probability distributions, whereas cross-entropy can be thought to calculate the total entropy between the distributions. Cross-entropy is also related to and often confused with logistic loss, called log loss. Although the two measures are derived from a different source, when used as loss functions for classification models, both measures calculate the same quantity and can be used interchangeably. In this tutorial, you will discover cross-entropy for machine learning.
A Gentle Introduction to Cross-Entropy for Machine Learning
Cross-entropy is commonly used in machine learning as a loss function. Cross-entropy is a measure from the field of information theory, building upon entropy and generally calculating the difference between two probability distributions. It is closely related to but is different from KL divergence that calculates the relative entropy between two probability distributions, whereas cross-entropy can be thought to calculate the total entropy between the distributions. Cross-entropy is also related to and often confused with logistic loss, called log loss. Although the two measures are derived from a different source, when used as loss functions for classification models, both measures calculate the same quantity and can be used interchangeably. In this tutorial, you will discover cross-entropy for machine learning.
Explaining Machine Learning to my Grandmother - WebSystemer.no
I chose that title in order to show to all of the readers that I'm trying to explain a complex concept as easy as possible. I also want to point out that I'm no expert in Machine Learning but I have been familiar with it for over 2 years now and currently I'm enrolled at Holberton School studying software engineering. Having said that, let me introduce some of the topics we're going to review. According to Expert System, "Machine learning is an application of artificial intelligence (AI) that provides systems the ability to automatically learn and improve from experience without being explicitly programmed. Machine learning focuses on the development of computer programs that can access data and use it learn for themselves."
Path Length Bounds for Gradient Descent
Figure 1: A two-dimensional convex function represented via contour lines. The function value is constant on the boundary of each such ellipse, and decreases as the ellipse becomes smaller and smaller. Let us assume we want to minimize this function starting from a point \(A\). The red line shows the path followed by a gradient descent optimizer converging to the minimum point \(B\), while the green dashed line represents the direct line joining \(A\) and \(B\). In today's post, we will discuss an interesting property concerning the trajectory of gradient descent iterates, namely the length of the Gradient Descent curve.
Eavesdrop the Composition Proportion of Training Labels in Federated Learning
Wang, Lixu, Xu, Shichao, Wang, Xiao, Zhu, Qi
--Federated learning (FL) has recently emerged as a new form of collaborative machine learning, where a common model can be learned while keeping all the training data on local devices. Although it is designed for enhancing the data privacy, we demonstrated in this paper a new direction in inference attacks in the context of FL, where valuable information about training data can be obtained by adversaries with very limited power . In particular, we proposed three new types of attacks to exploit this vulnerability. The first type of attack, Class Sniffing, can detect whether a certain label appears in training. The other two types of attacks can determine the quantity of each label, i.e., Quantity Inference attack determines the composition proportion of the training label owned by the selected clients in a single round, while Whole Determination attack determines that of the whole training process. We evaluated our attacks on a variety of tasks and datasets with different settings, and the corresponding results showed that our attacks work well generally. Finally, we analyzed the impact of major hyper-parameters to our attacks and discussed possible defenses. The emergence of federated learning (FL) enables multiple devices to learn a common model while keeping all the training data on their own devices. It allows for less resource consumption on the cloud and ensures the privacy at the same time. Multiple applications have benefited from FL, including mobile phones [1, 2, 3], wearable devices [4, 5], autonomous vehicles [6, 7], etc. In standard federated learning, all participants are required to train their local models. A random subset of clients will be selected each round, who will upload their gradient updates to the central server. Similar FL architectures can be found in [8, 9, 10, 11, 12, 13]. One interesting question here is about the security and privacy implication in the FL training process. Any characteristic of clients' private data needs to be protected carefully since it may reveal some important private information about the training data - e.g., the distribution of labels might show the diversity of participants. Similarly, what the training data consists of is also what attackers want to explore, i.e., can they determine the quantity proportion of different labels in the whole training dataset during the training process?
Topological based classification using graph convolutional networks
Abel, Roy, Benami, Idan, Louzoun, Yoram
In colored graphs, node classes are often associated with either their neighbors class or with information not incorporated in the graph associated with each node. We here propose that node classes are also associated with topological features of the nodes. We use this association to improve Graph machine learning in general and specifically, Graph Convolutional Networks (GCN). First, we show that even in the absence of any external information on nodes, a good accuracy can be obtained on the prediction of the node class using either topological features, or using the neighbors class as an input to a GCN. This accuracy is slightly less than the one that can be obtained using content based GCN. Secondly, we show that explicitly adding the topology as an input to the GCN does not improve the accuracy when combined with external information on nodes. However, adding an additional adjacency matrix with edges between distant nodes with similar topology to the GCN does significantly improve its accuracy, leading to results better than all state of the art methods in multiple datasets.