Re: Sort Stability With Date Boosting and Rounding

2011-02-23 Thread Markus Jelsma
Hi, This seems to be a tricky issue judging from the other replies. I'm just thinking out of the box now and the following options come to mind: 1) can you store the timestamp in the session in your middleware for each user? This way it stays fixed and doesn't change the order between requests.

Re: Sort Stability With Date Boosting and Rounding

2011-02-23 Thread Stephen Duncan Jr
That would improve things for recent documents, but documents that were close to each other, but a long time from NOW, would still have very small differences that would be susceptible to rounding errors that can cause results to get shuffled. Stephen Duncan Jr www.stephenduncanjr.com On Tue, Fe

Re: Sort Stability With Date Boosting and Rounding

2011-02-22 Thread Stephen Duncan Jr
No, the problem is that, due to rounding, sometimes the docs ARE considered ties, and therefore the secondary sort is used, but sometimes they don't round to exactly equal, and the tiebreaker isn't used, and the results get shuffled. Stephen Duncan Jr www.stephenduncanjr.com On Tue, Feb 22, 2011

Re: Sort Stability With Date Boosting and Rounding

2011-02-22 Thread Stephen Duncan Jr
The problem comes when you have results that are all the same natural score (because you've filtered them, with no primary search, for instance), and are very close together in time. Then, as you page through, the order changes. So the user experience is that they see duplicate documents, and mis

Re: Sort Stability With Date Boosting and Rounding

2011-02-22 Thread Markus Jelsma
Hi, You're right, it's illegal syntax to use other functions in the ms function, which is a pity indeed. However, you reduce the score by 50% for each year. Therefore paging through the results shouldn't make that much of a difference because the difference in score with NOW+2 minutes has a ne

Re: Sort Stability With Date Boosting and Rounding

2011-02-22 Thread Geert-Jan Brits
You could always use a secondary sort as a tie-breaker, i.e: something unique like 'documentid' or something. That would ensure a stable sort. 2011/2/23 Stephen Duncan Jr > I'm trying to use > > http://wiki.apache.org/solr/SolrRelevancyFAQ#How_can_I_boost_the_score_of_newer_documents > as > a bf

RE: Sort Stability With Date Boosting and Rounding

2011-02-22 Thread David Yang
One suggestion: use logarithms to compress the large time range into something easier to compare: 1/log(ms(now,date) -Original Message- From: Stephen Duncan Jr [mailto:stephen.dun...@gmail.com] Sent: Tuesday, February 22, 2011 6:03 PM To: solr-user@lucene.apache.org Subject: Sort Stabili