similar to: Participation in GSOC

Hello guys.I just read up about tf-idf schemes and want to implement it in Xapian (with some frequently used normalizations) as it will also give me a good hang of implementing a weighting scheme before I start working on implementing DFR schemes. I read the following as references and I think Ive understood it well and can write the hack :- 1.)

Hello guys.I am working on implementing the PL2 weighting scheme of the DFR framework by Gianni Amati. It uses the Poisson approximation of the Binomial as the probabilistic model (P), the Laplace law of succession to calculate the after effect of sampling or the risk gain (L) and within document frequency normalization H2(2) (as proposed by Amati in his PHD thesis). The formula for w(t,d) in

I was thinking about this some more: Is there a reason I can't just weight by some function of recency at indexing time? $weight = get_weight_based_on_recency(...); $tg->index_text($txt,$weight); If I wanted to allow the user the option of searching either in recency-weighted mode or not, I could index each document into 2 different databases, one with and one without. This avoids

Hi All I have just realized that if I set a query like 'green jelly bean' xapian will turn that query into 'green OR jelly OR bean' This causes documents containing just one of the words to be considered a 100% hit. The behavior I would like to see is that each word gives a 33.3% hit, so that a document containing all 3 words gets placed above a document with only 1 or 2

Hello Everyone, I am a second year graduate student at IIIT-Bangalore and my interest is in the field of Information Retrieval. I have successfully compiled Xapian from source and have implemented some examples. While going through the project list Weighting Schemes project is the one I was looking to contribute to. So i went through the xapian-core/weight where most of the schemes are already

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

On Tue, Aug 20, 2013 at 07:28:42PM +0800, jiangwen jiang wrote: > I think norm(t, d) in Lucene can used to caculate the number which is > similar to doc length(see norm(t,d) in > http://lucene.apache.org/core/3_5_0/api/all/org/apache/lucene/search/Similarity.html#formula_norm). It sounds similar (especially if document and field boosts aren't in use), though some places may rely on

Hello guys.I have begun work on writing my proposal as discussed on IRC and will submit a draft in a couple of days so that I can make it detailed and refine it after getting feedback. I wanted to know about the number of weeks a proposal should cover and also,is it okay if I set aside a buffer week somewhere in the middle of the summer for something like cleaning the code,working on the

Hi Xapianers: My name is Weixian Zhou, Computer Science student of University at Buffalo, State University of New York. I am interested in the project of posting list encoding improvements and weighting schemes. I have some questions toward them. 1) After read the comments in brass_postlist.cc, I am still not very clear about the detailed structure of postings list. If you can provide some simple

Hi, i'm wondering is there a possibility to do like ABCSok do (http://nyheter.abcsok.no/), to make "Main article" and "Same articles" collapsed to it. Like on http://news.google.com/?hl=en the same thing. "Parent" and "same article on other sites" (they do differ from each other a little bit). Maybe somebody know how to do that thing or where to read

Hey guys,I am a 3rd year Computer Science undergrad student.I a extremely interested in contributing code to the XAPIAN project. The work you people do sounds extremely fascinating and interesting.Can someone just give me a brief overview of how to proceed ?. I Can code in C,C++ and Python and have experience in Natural Lanuage Processing.Am also quite comfortable with NLTK and using Wordnet.Am

My code is not on Github. I am using the tarball as of now. The following it the error that occurred: http://pastebin.com/cVJrjUZX On Sun, Apr 13, 2014 at 8:16 PM, James Aylett <james-xapian at tartarus.org>wrote: > On 13 Apr 2014, at 15:37, Pallavi Gudipati <pallavigudipati at gmail.com> > wrote: > > > A linker error is encountered even after following the above

Hi, I am Chinmay Naik, an undergraduate in Computer Science at Bangalore Institute of Technology, Bangalore. I am an experienced programmer and good with C,C++,Python,Java,OpenGL and would love to participate in Gsoc-13. >From the ideas listed, i am interested to work on the project "posting list encoding improvements". I am a newbie to Xapian but would like to get involved and get a

Greetings, Using latest svn. I've noticed the following error when performing index merging: postlist: baseB blocksize=8K items=33962 lastblock=534 revision=1 levels=2 root=459 B-tree checked okay Tag containing meta information is corrupt. postlist table errors found: 1 I can still search on this index (I've only checked very small indexes), but merging is now a problem since I check

Olly Betts writes: > On Wed, May 17, 2017 at 09:08:32PM +0200, Jean-Francois Dockes wrote: > > I have a user reporting the following error during recoll indexing: > > > > flush() failed: Db block overwritten - are there multiple writers? > > > > "flush() failed" is from recoll, the rest is, I think the text of the Xapian > > exception.

Hi everyone, I'm a graduate student in Linguistics and Computer Science in the US, and I'm planning to propose a project to Xapian for GSoC that would implement and evaluate a variety of weighting schemes and ranking methods, allowing users to select different combinations. I have pretty thorough knowledge IR weighting and ranking, and I'm good in Java and Perl, and functional in

Olly Betts <olly at survex.com> wrote: > On Mon, Mar 27, 2023 at 11:22:09AM +0000, Eric Wong wrote: > > Olly Betts <olly at survex.com> wrote: > > > 10 seems too long. You want the mean word length weighted by frequency > > > of occurrence. For English that's typically around 5 characters, which > > > is 5 bytes. If we go for +1 that's:

> > >but it looked like > >you were suggesting that (for instance) the ID column in the data > >frame would only be specified by numeric index. > The parameter idField is only used to allow the user to specify a column whose row values will be used as unique identifiers. If it's required to index the idField then it should be separately included in the indexFields list

Hi, I have a user reporting the following error during recoll indexing: flush() failed: Db block overwritten - are there multiple writers? "flush() failed" is from recoll, the rest is, I think the text of the Xapian exception. This is with Xapian 1.4.3 on Linux (I asked for more details, should be coming). I don't think that I've ever seen this error, and I also

On Mon, Mar 27, 2023 at 11:22:09AM +0000, Eric Wong wrote: > Olly Betts <olly at survex.com> wrote: > > 10 seems too long. You want the mean word length weighted by frequency > > of occurrence. For English that's typically around 5 characters, which > > is 5 bytes. If we go for +1 that's: > > Actually, 10 may be too short in my case since there's a