Regression
Much Needed Mathematics for Machine Learning Algorithms
Data Science, Business Analytics or Business Intelligence all of these are birds of the same nest and they have some features in common, It is safe to say that they are same same but different. One of the common features is the algorithms and models to compare, analyse and predict stuff. Some of the most commonly used machine learning algorithms with mathematics are explained as follows. Linear regression tries to represent the relationship between two variables by fitting a linear equation. Where, One variable is illustrative, and the other is supposed to be dependent.
Topics to Avoid: Demoting Latent Confounds in Text Classification
Kumar, Sachin, Wintner, Shuly, Smith, Noah A., Tsvetkov, Yulia
Despite impressive performance on many text classification tasks, deep neural networks tend to learn frequent superficial patterns that are specific to the training data and do not always generalize well. In this work, we observe this limitation with respect to the task of native language identification . We find that standard text classifiers which perform well on the test set end up learning topical features which are confounds of the prediction task (e.g., if the input text mentions Sweden, the classifier predicts that the author's native language is Swedish). We propose a method that represents the latent topical confounds and a model which "unlearns" confounding features by predicting both the label of the input text and the confound; but we train the two predictors adversarially in an alternating fashion to learn a text representation that predicts the correct label but is less prone to using information about the confound. We show that this model generalizes better and learns features that are indicative of the writing style rather than the content.
Object-oriented programming for data scientists: Build your ML estimator
UPDATE: You will always find the latest Python script (with the linear regression class definition and methods) HERE. Use it to build further or experiment. Data scientists often come from a background which is quite far removed from traditional computer science/software engineering -- physics, biology, statistics, economics, electrical engineering, etc. But ultimately, they are expected to pick up a sufficient amount of programming/software engineering to be truly impactful for their organization and business. Being a Data Scientist does not make you a Software Engineer! And, what is at the heart of most modern programming languages and software engineering paradigms?
On EducationPython Regression Analysis: Statistics & Machine Learning - CouponED
This course will teach you regression analysis for both statistical data analysis and machine learning in Python in a practical hands-on manner. It explores the relevant concepts in a practical manner from basic to expert level. This course can help you achieve better grades, give you new analysis tools for your academic career, implement your knowledge in a work setting & make business forecasting related decisions...All of this while exploring the wisdom of an Oxford and Cambridge educated researcher. Most statistics and machine learning courses and books only touch upon the basic aspects of regression analysis. This does not teach the students about all the different regression analysis techniques they can apply to their own data in both academic and business setting, resulting in inaccurate modelling.
GADMM: Fast and Communication Efficient Framework for Distributed Machine Learning
Elgabli, Anis, Park, Jihong, Bedi, Amrit S., Bennis, Mehdi, Aggarwal, Vaneet
When the data is distributed across multiple servers, efficient data exchange between the servers (or workers) for solving the distributed learning problem is an important problem and is the focus of this paper. We propose a fast, privacy-aware, and communication-efficient decentralized framework to solve the distributed machine learning (DML) problem. The proposed algorithm, GADMM, is based on Alternating Direct Method of Multiplier (ADMM) algorithm. The key novelty in GADMM is that each worker exchanges the locally trained model only with two neighboring workers, thereby training a global model with lower amount of communication in each exchange. We prove that GADMM converges faster than the centralized batch gradient descent for convex loss functions, and numerically show that it is faster and more communication-efficient than the state-of-the-art communication-efficient centralized algorithms such as the Lazily Aggregated Gradient (LAG), in linear and logistic regression tasks on synthetic and real datasets. Furthermore, we propose Dynamic GADMM (D-GADMM), a variant of GADMM, and prove its convergence under time-varying network topology of the workers.
Rewarding High-Quality Data via Influence Functions
Richardson, Adam, Filos-Ratsikas, Aris, Faltings, Boi
We consider a crowdsourcing data acquisition scenario, such as federated learning, where a Center collects data points from a set of rational Agents, with the aim of training a model. For linear regression models, we show how a payment structure can be designed to incentivize the agents to provide high-quality data as early as possible, based on a characterization of the influence that data points have on the loss function of the model. Our contributions can be summarized as follows: (a) we prove theoretically that this scheme ensures truthful data reporting as a game-theoretic equilibrium and further demonstrate its robustness against mixtures of truthful and heuristic data reports, (b) we design a procedure according to which the influence computation can be efficiently approximated and processed sequentially in batches over time, (c) we develop a theory that allows correcting the difference between the influence and the overall change in loss and (d) we evaluate our approach on real datasets, confirming our theoretical findings.
Machine learning in agricultural and applied economics
This review presents machine learning (ML) approaches from an applied economist's perspective. We first introduce the key ML methods drawing connections to econometric practice. We then identify current limitations of the econometric and simulation model toolbox in applied economics and explore potential solutions afforded by ML. We dive into cases such as inflexible functional forms, unstructured data sources and large numbers of explanatory variables in both prediction and causal analysis, and highlight the challenges of complex simulation models. Finally, we argue that economists have a vital role in addressing the shortcomings of ML when used for quantitative economic analysis. Machine learning (ML) offers great potential for expanding the applied economist's toolbox. ML tools are beginning to be employed in economic analysis (Mรคrz et al., 2016; Crane-Droesch, 2017; Athey, 2019), while some researchers raise concerns about their transparency, interpretability and use for ...
#009 Activation functions and their derivatives Master Data Science
Now, it's clear that if we use a linear activation function (identity activation function), then the Neural Network will output linear output of the input. This loses much of the representational power of the neural network as often times the output that we are trying to predict has a non-linear relationship with the inputs. It can be shown that if we use a linear activation function for a hidden layer and sigmoid function for an output layer, our model becomes logistic regression model. Due to the fact that a composition of two linear functions is linear function, our area of implementing such Neural Network reduces rapidly. Rare implementation example can be solving regression problem in machine learning (where we use linear activation function in hidden layer).
A Tour of Machine Learning Algorithms
In this post, we will take a tour of the most popular machine learning algorithms. It is useful to tour the main algorithms in the field to get a feeling of what methods are available. There are so many algorithms that it can feel overwhelming when algorithm names are thrown around and you are expected to just know what they are and where they fit. I want to give you two ways to think about and categorize the algorithms you may come across in the field. Both approaches are useful, but we will focus in on the grouping of algorithms by similarity and go on a tour of a variety of different algorithm types.
Marginally-calibrated deep distributional regression
Klein, Nadja, Nott, David J., Smith, Michael Stanley
Deep neural network (DNN) regression models are widely used in applications requiring state-of-the-art predictive accuracy. However, until recently there has been little work on accurate uncertainty quantification for predictions from such models. We add to this literature by outlining an approach to constructing predictive distributions that are `marginally calibrated'. This is where the long run average of the predictive distributions of the response variable matches the observed empirical margin. Our approach considers a DNN regression with a conditionally Gaussian prior for the final layer weights, from which an implicit copula process on the feature space is extracted. This copula process is combined with a non-parametrically estimated marginal distribution for the response. The end result is a scalable distributional DNN regression method with marginally calibrated predictions, and our work complements existing methods for probability calibration. The approach is first illustrated using two applications of dense layer feed-forward neural networks. However, our main motivating applications are in likelihood-free inference, where distributional deep regression is used to estimate marginal posterior distributions. In two complex ecological time series examples we employ the implicit copulas of convolutional networks, and show that marginal calibration results in improved uncertainty quantification. Our approach also avoids the need for manual specification of summary statistics, a requirement that is burdensome for users and typical of competing likelihood-free inference methods.