Jordan Lecture Note-1: Introduction 第一部分要整理的是Jordan的讲义,这份讲义是我刚进实验室时我们老师给我的第一个任务,要求我把讲义上的知识扩充出去,然后每周都要讲给他听.如果有需要这份讲义的话,请留言,我会用邮件发给你. 首先,我来说说机器学习这个东西.刚进实验室,我根本连什么是机器学习都不知道,听到这个名词后的第一反应是机器人,心想估计是搞硬件的.后来才发现其实机器学习更偏向于后面两个字,也就是“学习”.打个不恰当的比方吧,人类在婴儿时期,还无法对世上…

Jordan Lecture Note-3:梯度投影法 在这一节,我们介绍如何用梯度投影法来解如下的优化问题: \begin{align} \mathop{\min}&\quad f(x)\nonumber\\\mathop{s.t.}&\quad \mathbf{A}_1 x\leq b_1\nonumber\\&\quad \mathbf{A}_2x= b_2\label{equ:originalModel}\end{align} 其中$x\in\mathbb{R}^n,\ma…

题目1 : Colorful Lecture Note 时间限制:10000ms 单点时限:1000ms 内存限制:256MB 描述 Little Hi is writing an algorithm lecture note for Little Ho. To make the note more comprehensible, Little Hi tries to color some of the text. Unfortunately Little Hi is using a plain…

Little Hi is writing an algorithm lecture note for Little Ho. To make the note more comprehensible, Little Hi tries to color some of the text. Unfortunately Little Hi is using a plain(black and white) text editor. So he decides to tag the text which…

Colorful Lecture Note 时间限制:10000ms 单点时限:1000ms 内存限制:256MB 描述 Little Hi is writing an algorithm lecture note for Little Ho. To make the note more comprehensible, Little Hi tries to color some of the text. Unfortunately Little Hi is using a plain(black…

#1103 : Colorful Lecture Note 时间限制:10000ms 单点时限:1000ms 内存限制:256MB 描述 Little Hi is writing an algorithm lecture note for Little Ho. To make the note more comprehensible, Little Hi tries to color some of the text. Unfortunately Little Hi is using a pla…

Lecture 3(part 1) Divide and conquer 1. the general paradim of algrithm as bellow: 1. divide the problem into subproblems; 2. conqure each subproblems recrusively; 3. combine solution 2. Some typical problem (part 1) the matrix mutiplication(strassen…

Kernels 我们首先来回顾kernel函数的定义:一个函数$K(x,y)$为kernel函数当且仅当对$\forall g, \int K(x,y)g(x)g(y)dxdy\geq 0$成立.另外,根据Mercer's theorem,存在一个映射$\Phi$使$K(x,y)=\langle \Phi(x),\Phi(y)\rangle$,并且对任意有限的点,kernel矩阵是半正定的. 一.核函数的封闭性 Hadamard product: $$\mathbf{A}\circ\mathbf…

Maximal Margin Classifier Logistic Regression 与 SVM 思路的不同点:logistic regression强调所有点尽可能远离中间的那条分割线,而SVM则强调最靠近分割线的点于分割线的距离仅可能的远. 定义间隔函数:$\hat{r}^{(i)}=y^{(i)}(w^\prime x^{(i)}+b)$.当$y^{(i)}=1$时,$w^\prime x^{(i)}+b>0$:当$y^{(i)}=-1$时,$w^\prime x^{(i)}+b<…

Kernel典型相关分析 (一)KCCA 同样,我们可以引入Kernel函数,通过非线性的坐标变换达到之前CCA所寻求的目标.首先,假设映射$\Phi_X: x\rightarrow \Phi_X(x), \Phi_Y: y\rightarrow \Phi_Y(y)$,记$\mathbf{\Phi_X}=(\Phi_X(x_1),\Phi_X(x_2),\cdots,\Phi_X(x_p))^\prime, \mathbf{\Phi_Y}=(\Phi_Y(y_1),\Phi_Y(y_2),\cd…