Some questions
"Steve" <[email protected]> Sat, 23 May 2009 01:00:54 +0200
| Newsgroups | gmane.mail.spam.crm114 |
|---|---|
| Message-ID | <[email protected]> |
Hello all I don't know if the list is the right place to ask, but I try. I would like to understand better how SBPH and OBF is working. According to the CRM114 documentation I have made the following table: W = Weight C = Complexity or matched words S = Sparse F = Features SBPH: ----+---+---+--------------------------------- W | C | S | F ----+---+---+--------------------------------- 1 | 1 | 0 | jumped 4 | 2 | 0 | fox jumped 4 | 3 | 1 | brown <skip> jumped 16 | 3 | 0 | brown fox jumped 4 | 4 | 2 | quick <skip> <skip> jumped 4 | 4 | 2 | quick <skip> fox jumped 16 | 4 | 1 | quick brown <skip> jumped 64 | 4 | 0 | quick brown fox jumped 4 | 5 | 3 | the <skip> <skip> <skip> jumped 16 | 5 | 2 | the <skip> <skip> fox jumped 16 | 5 | 2 | the <skip> brown <skip> jumped 64 | 5 | 1 | the <skip> brown fox jumped 16 | 5 | 2 | the quick <skip> <skip> jumped 64 | 5 | 1 | the quick <skip> fox jumped 64 | 5 | 1 | the quick brown <skip> jumped 256 | 5 | 0 | the quick brown fox jumped ----+---+---+--------------------------------- For calculating the weight I used the following OpenOffice.org Calc formula: =2^(2*(Complexity-Sparse-1)) OSB: -----+---+---+--------------------------------- W | C | S | F -----+---+---+--------------------------------- 3125 | 2 | 0 | fox jumped 256 | 3 | 1 | brown <skip> jumped 27 | 4 | 2 | quick <skip> <skip> jumped 4 | 5 | 3 | the <skip> <skip> <skip> jumped -----+---+---+--------------------------------- For calculating the weight I used the following OpenOffice.org Calc formula: =(5-Sparse)^(5-Sparse) I used 5 as the window size. Is the above table right? If not, what errors have I made? If I understand the documentation right, then the weight is used to calculate the probability for a class (either spam or ham). Can one explain me what role the count of a feature inside the CRM Sparse Spectra file plays? I mean assuming the feature "fox jumped" and assuming that feature was found 500 times in the class ham and 100 times in the class spam. How does that 500 and/or 100 count play a role in calculating the probability? Does that even play a role or is it unimportant how many times a features has been learned before? What happens when CRM114 is saving the data inside the CSS file? Does it save the feature "quick <skip> <skip> jumped" as a concatenated hash value (replacing the <skip> with some kind of delimiter) or does it save just one hash (for the above feature) and at run time after parsing and hashing a message (and therefore knowing the complexity and sparse of a feature) it compares the calculated (in memory) feature with the one found in the CSS file? I mean: Assuming the feature: "quick <skip> <skip> jumped" Assuming hashing "quick" would be: "1111111111111111" Assuming hashing "jumped" would be: "2222222222222222" Assuming hashing the whole feature would be: "12345678ABCDEF09" Does CRM114 now save "12345678ABCDEF09" or does it save "1111111111111111" + some kind of delimiter for <skip> + some kind of delimiter for <skip> + "2222222222222222"? Another thing I don't understand is this slighting window of 5. Assuming the following content: 1 2 3 4 5 6 7 8 9 0 Does the window now slide like this: "1 2 3 4 5" and then "6 7 8 9 0" Or does it overlap: "1 2 3 4 5" and then "2 3 4 5 6" and then "3 4 5 6 7 8" and then "4 5 6 7 8 9" and then "5 6 7 8 9 0" and it quits because it can not allocate again 5 words. Or how is this slighting window working? Sorry for all the stupid questions, but I really would like to better understand how the things are working inside CRM114. If the list is the wrong place to ask that questions and you know where I could ask them, then just let me know. Or maybe you know some document better describing how things work in CRM114 then just let me know. // Steve -- Neu: GMX FreeDSL Komplettanschluss mit DSL 6.000 Flatrate + Telefonanschluss für nur 17,95 Euro/mtl.!* http://portal.gmx.net/de/go/dsl02 ------------------------------------------------------------------------------ Register Now for Creativity and Technology (CaT), June 3rd, NYC. CaT is a gathering of tech-side developers & brand creativity professionals. Meet the minds behind Google Creative Lab, Visual Complexity, Processing, & iPhoneDevCamp asthey present alongside digital heavyweights like Barbarian Group, R/GA, & Big Spaceship. http://www.creativitycat.com