Articles by al3xandr3

Monitoring Productivity II – the Others

September 30, 2011 | al3xandr3

In previous Monitoring Productivity Experiment post I looked into the hours I spent in computer, now will look into the hours Others spend in computer, which is far more interesting :) To find things like what day people spend more time on computer, ho... [Read more...]

Machine Learning Ex5.2 – Regularized Logistic Regression

March 20, 2011 | al3xandr3

Exercise 5.2 Improves the Logistic Regression implementation done in Exercise 4 by adding a regularization parameter that reduces the problem of over-fitting. We will be using Newton's Method. Data Here's the data we want to fit. # linear regression # load the data mydata = read.csv("http://spreadsheets.google.com/pub?key=0AnypY27pPCJydHZPN2... [Read more...]

Machine Learning Ex5.1 – Regularized Linear Regression

March 18, 2011 | al3xandr3

Exercise 5.1 Improves the Linear Regression implementation done in Exercise 3 by adding a regularization parameter that reduces the problem of over-fitting. Over-fitting occurs especially when fitting a high-order polynomial, that we will try to do here. Data Here's the points we will make a model from: # linear regression mydata = read.csv("... [Read more...]

Machine Learning Ex3 – multivariate linear regression

March 8, 2011 | al3xandr3

Exercise 3 is about multivariate linear regression. First part is about finding a good learning rate (alpha) and 2nd part is about implementing linear regression using normal equations instead of the gradient descent algorithm. Data As usual hosted in google docs: mydata = read.csv("http://spreadsheets.google.com/pub?key=0AnypY27... [Read more...]

Machine Learning Ex2 – linear regression

February 24, 2011 | al3xandr3

Andrew Ng has posted introductory machine learning lessons on the OpenClassRoom site. I've watched the first set and will here solve Exercise 2. The exercise is to build a linear regression implementation, I'll use R. The point of linear regression is to come up with a mathematical function(model) that represents ... [Read more...]

Weight Loss Predictor

February 5, 2011 | al3xandr3

Got for 2010 Xmas a very cool book called the "4 Hour Body"(thanks Jose Santos) written by Tim Ferriss who write a previous favorite of mine about productivity, the 4 hour work week. Its an interesting book, because it has a scientific approach, it ... [Read more...]

Monitoring Productivity Experiment

October 20, 2010 | al3xandr3

For over a year now, i've been collecting how much time i spend in computer and how much of it is actually used in creative/productive activities. By productive activity i mean that the time spent in text editor(emacs), terminal, excel or a datab... [Read more...]

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