二分类:Logistic regression 多分类:Softmax分类函数 对于损失函数,我们求其最小值, 对于似然函数,我们求其最大值. Logistic是loss function,即: 在逻辑回归中,选择了 “对数似然损失函数”,L(Y,P(Y|X)) = -logP(Y|X). 对似然函数求最大值,其实就是对对数似然损失函数求最小值. Logistic regression, despite its name, is a linear model for classification…
Example: Polynomial Curve Fitting The goal of regression is to predict the value of one or more continuous target variables t given the value of a D-dimensional vector x of input variables. 什么是线性回归?线性回归的目标就是要根据特征空间是D维的输入x,预测一个或多个连续的目标值变量,大多数情况下我们研究的目…
NB: 因为softmax,NN看上去是分类,其实是拟合(回归),拟合最大似然. 多分类参见:[Scikit-learn] 1.1 Generalized Linear Models - Logistic regression & Softmax 感知机采用的是形式最简单的梯度 Perceptron and SGDClassifier share the same underlying implementation.In fact, Perceptron() is equivalent to S…
ON THE EVOLUTION OF MACHINE LEARNING: FROM LINEAR MODELS TO NEURAL NETWORKS We recently interviewed Reza Zadeh (@Reza_Zadeh). Reza is a Consulting Professor in the Institute for Computational and Mathematical Engineering at Stanford University and a…
chapter 3: Linear Methods for Regression 第3章:回归的线性方法 3.1 Introduction A linear regression model assumes that the regression function \(E(Y\mid X)\) is linear in the inputs \(X_1, \ldots , X_p\). Linear models were largely developed in the precomputer…
网易公开课,第4课 notes,http://cs229.stanford.edu/notes/cs229-notes1.pdf 前面介绍一个线性回归问题,符合高斯分布 一个分类问题,logstic回归,符合伯努利分布 也发现他们有些相似的地方,其实这些方法都是一个更广泛的模型族的特例,这个模型族称为,广义线性模型(Generalized Linear Models,GLMs) The exponential family 为了介绍GLMs,先需要介绍指数族分布(exponential fami…
Linear and Logistic Regression in TensorFlow Graphs and sessions TF Ops: constants, variables, functions TensorBoard Lazy loading Linear Regression: Predict life expectancy from birth rate Let's start with a simple linear regression example. I hope y…
1.1.10. Bayesian Ridge Regression 首先了解一些背景知识:from: https://www.r-bloggers.com/the-bayesian-approach-to-ridge-regression/ In this post, we are going to be taking a computational approach to demonstrating the equivalence of the bayesian approach and ri…