cmu machine learning course

This is a machine learning course that coursera on fire, and the instructor is Andrew Ng. In the process of looking at the neural network, I did find that I had a problem with a weak foundation and some basic concepts, so I wanted to take this course to find a leak. The current plan is to see the end of the neural netw

Tags: machine learning, data mining, overfitting, deterministic noiseCourse introductionThis section describes the problem of over-generalization in machine learning. The author points out that one of the ways to differentiate a professional-level player from a hobbyist is how they deal with the problem of preparation.

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+ y

does not introduce a matrix, which is easy to calculate and can be correctly executed if there are few samples. The multi-element model is complex to calculate after the matrix is introduced. to calculate the inverse of the matrix, the model must be executed when the sample value is greater than the feature value. ------------------------------------------Weak split line---------------------------------------------- Although exception detection is mentioned in this article, it is used to in

This series is a personal learning note for Andrew Ng Machine Learning course for Coursera website (for reference only)Course URL: https://www.coursera.org/learn/machine-learning Exerci

(that is, Xi in {1,..., | v|} Value in | V| is the vocabulary of the lexicon), n-word messages will be represented by a vector of length n, and the length of the vectors for different articles will probably not be the same.In the multiple event model, we assume that this is the case with the message: first determine whether this is a spam message through P (Y), and then independently determine each word by multiple distributions P (x|y). The probability of the final generation of the entire mes

Andrew ng Machine Learning course 17 (2)Disclaimer: Reference Please specify source http://blog.csdn.net/lg1259156776/Description: This paper mainly introduces the use of value iteration and policy iteration two kinds of iterative algorithms to solve MDP problem, also introduced in practical application how to accumulate "experience" to update the transfer probab

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

Model (how to simulate)---strategy (risk function)-algorithm (optimization method)First section:Basic concepts and classifications of machine learningSection II:Linear regression, least squaresBatch gradient descent (BGD) and random gradient descent (SGD)Section III:Over-fitting, under-fittingNon-parametric learning algorithm: Local weighted regressionThe probability angle interprets the linear regression.

Extremely light of a semester finally passed, summer vacation intends to learn the big step down this machine learning techniques.The first lesson is the introduction of SVM, although I have learned it before, but I heard a feeling is very rewarding. The blogger sums up a ballpark figure, and the specifics areTo listen: http://www.cnblogs.com/bourneli/p/4198839.htmlThe blogger sums it up in detail: http://w

: One-to-multiple ) Sometimes the problem is not as simple as determining whether a patient's tumor is malignant or benign. For example, determining whether the weather is sunny, cloudy, raining, Or snowing is necessary. We can use a line to separate binary classification. What about multiclass classification? There is a simple method, that is, to separate only one category at a time. There are several categories to construct several decision edge, that is, severalH (x): In th

dimension.Finally, we propose a method for solving overfitting, including data cleaning/pruning, data hinting, regularization (regularization), confirmation (validation), andTo drive for example to illustrate the role of these methods, the latter two methods are also the contents of the following two lessons.Data cleaning/pruning is to correct or delete the wrong sample points, processing is simple, but usually such sample points are not easy to find.Data hinting generate more sample numbers by

This section is about regularization, in the optimization of the use of regularization, in class when the teacher a word, not too much explanation. After listening to this class,To understand the difference between a good university and a pheasant university. In short, this is a very rewarding lesson.First of all, we introduce the reason for regularization, simply say that the complex model with a simple model to express, as to how to say, there is a series of deduction hypothesis, very creative

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represent the right side of the inequality and Delta to represent ε. So we have: We have previously studied the probability of occurrence of bad events. Now let's look at the probability of occurrence of optimistic events: P [| ein (G)-eout (G) | Use Ω (n, H, Delta) instead of ε to get the desired good event definition: | eout-Ein | Ω is positively related to N, Delta, and h or VC. We ignore the Ω parameter first, so there are: | eout-Ein | In most cases, eout is larger than EIN, because w

+ 1 parameter: x0 -- x256. We hope to use machine learning to determine the values of all these parameters. However, with so many parameters, machine learning may take a lot of time to complete, and the effect is not necessarily good. We can see that some pixels are not needed, so we should extract some features from

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 a

Open Course address: https://class.coursera.org/ml-003/class/index INSTRUCTOR: Andrew Ng1. unsupervised learning introduction (Introduction to unsupervised learning) We mentioned one of the two main branches of machine learning-supervised

hypothesis closest to F and F. Although it is possible that a dataset with 10 points can get a better approximation than a dataset with 2 points, when we have a lot of datasets, then their mathematical expectations should be close and close to F, so they are displayed as a horizontal line parallel to the X axis. The following is an example of a learning curve: See the following linear model: Why add noise? That is the interference. The purpose is to

I've been talking about why machines can learn, and starting with this lesson are some basic machine learning algorithms, i.e. how machines learn.This lesson is about linear regression, starting with the minimization of Ein, introducing the Hat Matrix to understand the geometric meaning. Finally, the linear regression and binary classification are compared, and the reason why linear regression can be used t