similar to: [GSOC 2013] Question about indexing INEX dataset

Hi Parth, I?ve implemented SVMRanker class and also sorted out most of current Letor APIs. Now I?m trying to use INEX dataset to verify my implement. But I stuck in the indexing part. You said in the documentation that we have to add prefix when indexing. Also I notice that you set some metadata in omindex.cc of your version. But the omindex.cc has changed since 2011. I think that?s why my result

On Tue, Mar 11, 2014 at 03:20:31PM +0100, Parth Gupta wrote: > > > > On current trunk, we index the title with prefix "S" by default in > > omindex, though with a wdf inc of 5 rather than 1: > > > > indexer.index_text(title, 5, "S"); > > > > So I don't think you need that change to omindex now. > > Yes, but please

Hi Olly, Wouldn't setting the weight of terms in title back to normal (e.g. 5 to 1) by below line, automatically adjust the wdfs and field lengths? indexer.index_text(title, 5, "S"); -> indexer.index_text(title, 1, "S"); if it does not then we should include that part in the patch too. I like to create a patch for xapian-letor for resolving common code of xapian.

On Tue, Mar 11, 2014 at 12:02:15PM +0100, Parth Gupta wrote: > During the indexing with omindex, only you need to make sure is indexing > with prefix 'S' for title as explained here in Letor documentation: > xapian-letor/docs/letor.rst > > Previously when I edited omindex.cc it was modified as can be seen >

Thanks for your reply! For the third question: In https://inex.mmci.uni-saarland.de/data/documentcollection.jsp, I can find inex2010-article.qrels in 2010 assessment, but can?t find query files. Could you send me the link? I have registered on INEX website. And I also need to download ``INEX 2009 collection without annotation tags: (unofficial)`` on

For unsupervised approaches like BM25 this approach works well but letor does not need special weighting for title in this form as it itself assigns weights to title features separately. But I see your concern it would be a problem when BM25 is used on the index with this setup. Hence its preferable to take a note of this uplift in title weight for xapian-letor and normalize it everywhere

Hi, I've read the code of letor module. And I have some questions about it: 1. In https://github.com/rishabhmehrotra/xapian/blob/master/xapian-letor/letor_internal.cc#L299, there is a write_to_file method, which save RankList into ?train.txt?. But the format for ?train.txt? is different from the one mentioned in http://trac.xapian.org/wiki/GSoC2011/LTR/Notes#QueryLevelNorm. And in

Hi all, Thank you for giving me the opportunity to work with Xapian :) I am Jiarong Wei, a third year undergraduate student in Zhejiang University, China. In GSoC 2014, I will work on Letor module with Hanxiao Sun. Here are some questions I encountered these days, 1. In letor.cc, we have two parts of functions: the training part and the ranking part. I?ll use SVMRanker as an example. The

Hi, I am Jiarong Wei (irc: VcamX). I?m a 3rd year computer science student at Zhejiang University, China. I?m very willing to contribute to Xapian as part of GSoC 2014. Now I?m at Simon Fraser University, Canada, as an exchange student. I?ll go back to China on the end of April. I think it doesn?t matter I?ll change the time zone :) From the list of project?s ideas, Learning to Rank interests me

Just to add on top of what Olly has already mentioned. > > Now, I'm reading the resources provided on ideas' page. Do you have > > any other suggestions of knowing more about the letor? > > And I'd like to test the function of letor. But I can't find code > > example. Can u give me some suggestions? > > Hopefully Parth can help here. > In order

Hello All, I am trying to index a collection of files. Details of the collection is given below. Types of Files: text files with .txt extension Size of the collection: 11400 documents [1.6 GB] This takes a lot of time to index and indexing for last 20 hrs or so. I am using omindex. I notice that around 2900 docs are indexed very smoothly and suddenly after that indexing becomes very sluggish.

Dear all, My name is Hanxiao Sun and I am a master student in the University of Chinese Academy of Sciences. I am so glad to be selected by Xapian as the GSoC student. This is my first time to work with open source community. I hope I can do a good job with you in this summer ! In my proposal, I followed the scope of the LTR project on the ideas page. But, after the interview, it seems to need

Hello, I'm Ayush from New Delhi, India. I am interested in Letor Stabilisation project for GSoC. I have a good background in machine learning. Sorry for getting in so late, university exams were holding me back. I'll try to cover as much as I can in the coming week. I am following the plan of attack suggested on the project page. Following are the things that I have completed: 1.

Olly (looking at commit logs, I think this is your dept :-) For apps which re/index files frequently and need format conversion, I'd like to propose a patch for one of... Omindex library (thread safe): Omindex::init(options) // struct Omindex::options { ... } initialize mime_map, store default options session = new Omindex::Session(db_pathname) user threads use different sessions

Hi, all -- I want to do Plain Old Omindex'ing *but* the mapping between my documents' filenames and the URLs where I hope search users to find them is, uh..., strange. The simplest thing (to me) would be to run omindex for each document, e.g. omindex --no-delete -U /cool-url-1 /funky/doc/file-blah.pdf omindex --no-delete -U /cool-url-7 /doc/funky/ohmy/blah-file.txt ... and so on...

All, I've run into a couple of things using omega/omindex under cygwin. I don't think I'd attribute them to xapian, omega or omindex, but wanted to get them out to the list so that if anyone else should run into these things down the road, hopefully someone will remember and be able to help. 1) after compiling and building omega, and doing make install, I get a set violation when

Hi. I am writing a python equivalent of omindex (we are using scriptindex currently - but I wanted to use omindex instead, and extend it to work with our internal file format.. BUT did not want to compile code if possible... so anyway). I have tried to keep the code as close to possible to the omindex native code, but am facing a bit of confusion: what exactly is the reason for omindex to take

I would really like to try out the features in the patch above. But I can't ever seem to get the resulting omindex.cc to "make". I tried updating to rev 10801 from the SVN then run /bootstrap but then I seem to get errors compiling everything when I try and do "make" (I'm using ubuntu 8.10). So I thought I'd try an apply the patch to the latest stable version

Given a directory tree like ... /foo | +-- A | +-- B | +-- C ... what is the best way to index A and C into a single Xapian database? AFAIK the alternatives are: omindex --db /my_db --no-delete /foo /foo/A omindex --db /my_db --no-delete /foo /foo/B or omindex --db /my_A_db /foo /foo/A omindex --db /my_B_db /foo /foo/B xapian-compact /my_A_db /my_B_db /my_db The first alternative does not

Hi Parth, I implemented DFR algorithms in Xapian as a part of GSOC last year under the mentorship of Olly. This year, I want to work on analyzing and optimizing the performance of the DFR algorithms and comparing them with BM25.I also want to work on profiling the query expansion schemes and test the relevance(precision and recall) / speed(time taken) of the