#11




Re: Libsvm
I am trying to get the digits data in the form that Libsvm (the windows command line version) can use. I need to convert the two input data into the form '1:0.12121'. In other words, append the integer and :. Since I am new to Matlab (which I have used throughout the course), can anyone explain how to transform the data. While I can make it into a string, I'm not sure this will be correctly read by Libsvm.
Thanks. 
#12




Re: Libsvm
In the link about Octave (hope it is == to Matlab in this respect)
http://octave.1599824.n4.nabble.com/...td1632472.html there is:  >I would like to read an ascii data file with 3 columns of integers >separated by a space, and an unknown number of rows into 3 vectors or a >matrix with 3 columns. Try data = load ("ascii", "yourfile.txt") Ben  HTH 
#13




Re: Libsvm
Thanks. I will try it later today.

#14




Re: Libsvm
Pleasy, some one who understand how this libsvm works tell us how to go through week 8 problems.
I tryed to install libsvm in Octave, thats what I have: Quote:
Quote:
1  polynomial: (gamma*u'*v + coef0)^degree but didnt find in list Thats what I have in last iteration: Quote:
Actually I am prefer using my code from week7, but with upper bound C and some others. But this 7291 X 7291 matrix... 
#15




Re: Libsvm
I don't get any reasonable output:/
I made training sets where in ex. 0vsall i changed every zero with +1 and every other label number with 1 then i fed it libsvm using "svmtrain.exe t 1 d 2 g 1 r 1 v 10 c 0.01 0vsall.train 0vsall.model" after that i fed the model and the training set to svm.predict.exe but it just says everything is 1 (so not a 0) which essentialy means every 0 is mis clasified but that can't be the point of the exercise right? Can someone tell me where I'm doing something wrong? 
#16




Re: Libsvm
Quote:

#17




Re: Libsvm
Interesting suggestion! I was also trying a couple of hours to find my bug when I realized this is actually the result. Will look into wi par to, quite curious if that works or if the dataset itself is just not separable.

#18




Re: Libsvm
well I thought so too (even during the lectures I wondered what to do not to skew the result by having unequal ammounts of +1 and 1 data) but since it's a 2nd order kernel it would benefit from even circling only one of the +1 labeled values yet it won't even do that which seems unreasonable.

#19




Re: Libsvm
Let me know how you get on with the wi? I won't be able to test until tomorrow so will post my findings, if any, then?
I found this whch explains in more detail: http://www.csie.ntu.edu.tw/~cjlin/papers/libsvm.pdf See section 6  Unbalanced Data and Solving the Twovariable (page 26) 
#20




Re: Libsvm
oh yeah you can balance using wi but don't do it (if youd have to it would be stated in the homework) also there is no point in balancing since well.... any number occurs fewer times than all the others combined so in essence you'd be balancing a skew which should be there (also I think it might be some sort of data snooping(?))
anyway I found my problem hint: make sure your input has the correct form 
Thread Tools  
Display Modes  

