LFD Book Forum Question 10
 User Name Remember Me? Password
 Register FAQ Calendar Mark Forums Read

 Thread Tools Display Modes
#11
03-13-2013, 07:09 AM
 SeanV Junior Member Join Date: Jan 2013 Posts: 8
Re: Question 10

Quote:
 Originally Posted by yaser Correct. The solution was also given in slide 11 of Lecture 12 (regularization).
yes my point was how do you solve this numerically - given that people will already have a good least squares code ( doing SVD on Z to avoid numerical ill conditioning), there is no need to implement (poorly) a new regularised least squares solver

you can just add a few data points at the end of your training data and feed it into your least squares solver. ie
\lambda |w|^2 = \sum_i (y_i-\sqrt(lambda)w_i)^2

ie if w is d dimensional you append to your Z matrix the additional matrix=sqrt(lambda)*eye(d) and append a d vector of zeros to your y

(eye(d) is d by d identity matrix) [ but this is much better explained in the notes i linked to]

 Tags question 10

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is Off Forum Rules
 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home General     General Discussion of Machine Learning     Free Additional Material         Dynamic e-Chapters         Dynamic e-Appendices Course Discussions     Online LFD course         General comments on the course         Homework 1         Homework 2         Homework 3         Homework 4         Homework 5         Homework 6         Homework 7         Homework 8         The Final         Create New Homework Problems Book Feedback - Learning From Data     General comments on the book     Chapter 1 - The Learning Problem     Chapter 2 - Training versus Testing     Chapter 3 - The Linear Model     Chapter 4 - Overfitting     Chapter 5 - Three Learning Principles     e-Chapter 6 - Similarity Based Methods     e-Chapter 7 - Neural Networks     e-Chapter 8 - Support Vector Machines     e-Chapter 9 - Learning Aides     Appendix and Notation     e-Appendices

All times are GMT -7. The time now is 01:43 PM.

 Contact Us - LFD Book - Top