stanford sql course

I. Introduction of the CourseStanford University launched an online natural language processing course in Coursera in March 2012, taught by the NLP field Daniel Dan Jurafsky and Chirs Manning:https://class.coursera.org/nlp/The following is the course of the study notes, to the main course ppt/pdf, supplemented by other reference materials, into the personal devel

It should be this time last year, I started to get into the knowledge of machine learning, then the introductory book is "Introduction to data mining." Swallowed read the various well-known classifiers: Decision Tree, naive Bayesian, SVM, neural network, random forest and so on; In addition, more serious review of statistics, learning the linear regression, but also through Orange, SPSS, R to do some classification prediction work. But the external said that they are engaged in machine learning

is more than one, the Newton method iterates over the rule:Newton's method usually has a faster convergence rate than the batch gradient, and it takes a much smaller number of iterations to get close to the minimum value. However, when the parameters of the model are many (n), the computational cost of the Hessian matrix will be large, resulting in a slower convergence rate, but when the number of arguments is not long, the Newton method is usually much faster than the gradient descent.Summariz

Stanford University machine Learning lesson 10 "Neural Networks: Learning" study notes. This course consists of seven parts: 1) Deciding what to try next (decide what to do next) 2) Evaluating a hypothesis (Evaluation hypothesis) 3) Model selection and training/validation/test sets (Model selection and training/verification/test Set) 4) Diagnosing bias vs. variance (diagnostic deviation and variance) 5) Reg

be trained and predicted immediately, which is called Online learning. each of the previously learned models can do online learning, but given the real-time nature, not every model can be updated in a short time and the next prediction, and the perceptron algorithm is well suited to do online learning:The parameter Update method is: if hθ (x) = y is accurate, the parameter is not updated otherwise, θ:=θ+ yx (in fact, this formula and gradient descent update strategy is the same, but the class l

is that only the input paradigm is provided for this network, and it automatically identifies its potential class rules from those examples. When the study is complete and tested, it can also be applied to new cases. A typical example of unsupervised learning is clustering. The purpose of clustering is to bring together things that are similar, and we do not care what this class is. Therefore, a clustering algorithm usually needs to know how to calculate the similarity to begin to work.

Stanford ml Open Course Notes 15In the previous note, we talked about PCA ). PCA is a direct dimensionality reduction method. It solves feature values and feature vectors and selects feature vectors with larger feature values to achieve dimensionality reduction.This article continues with the topic of PCA, including one application of PCA-LSI (Latent Semantic Indexing, implicit semantic index) and one imple

(normalization): It mainly includes capitalization conversion, stemming, simplified conversion and so on. Segmentation (sentence segmentation and decision Trees): Like!? Such symbols are clearly divided in meaning, but in English. " "will be used in a variety of scenarios, such as the abbreviation" INC "," Dr ",". 2% "," 4.3 "and so on, can not be processed by simple regular expression, we introduced the decision tree classification method to determine whether th

intoScoreValues(3,'3-105', -)Insert intoScoreValues(4,'3-105', -)Insert intoScoreValues(5,'3-105', -)Insert intoScoreValues(6,'3-105', -)--Business: To ensure the complete implementation of the entire process, all without problems, unified submission, once there is a problem, back to the origin. Like bank transfers.Begin Tran--z The start of the transaction--start writing the process statement--After the statement is finishedIf @ @ERROR >0Rollback tran--ROLLBACK TRANSACTIONElseCommit Tran--

This text has been reprinted online, and some SQL statements are suitable for use in application systems. Some "reports" have a heavier feeling, mainly to review the former. This text has been reprinted online, and some SQL statements are suitable for use in application systems. Some "reports" are more likely to be used, mainly to review the former. 50 common SQL