309069 (11) [Avatar] Offline
#1
Hi
I'm looking for more information on the Structure of Instances (Fig 1.4, page 8 ) in particular the LibSVM syntax described: class label, feature vector [feature ID, feature value]. I've tried to Google the key words but I end up with Support Vector Machine-related stuff ...
Can you please provide some links and/or bibliography on this subject ?
Thank you in advance
Jeff Smith (14) [Avatar] Offline
#2
The LibSVM format was originally developed for use in a support vector machines library called LibSVM, but it's now used as generally supported sparse format for representing instances. I discuss this a bit in the forthcoming Chapter 5.

There's not much to it, but here's some basic info, which should help you understand how it's used before Chapter 5 is released:

http://stats.stackexchange.com/questions/61328/libsvm-data-format
http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#/Q03:_Data_preparation
https://www.quora.com/What-is-this-data-format-in-LIBSVM-training-dataset