Max Wilson kicked off with a talk on exploratory search and ’searching for leisure’. His Search Interface Inspector looks like a fascinating resource, and we heard about how he and his team have been constructing a taxonomy for the different kinds of search people do, using Twitter as a data source.

Martina Schell was next with details of Travel Match, a holiday search engine that’s trying to do for holidays what our customer Mydeco is doing for interior design: scrape/feed/gather as much holiday data as you can, put it all into a powerful search engine and build innovative interfaces on top. They’ve tried various interfaces including a ‘visual search’, but after much user testing have reined back their ambitions somewhat – however they’re still unique in allowing some very complex queries of their data. Interestingly, one challenge they identified is how to inform users that one choice (say, airport to fly from) may affect the available range of other choices (say, destinations) – apparently users often click repeatedly on ‘greyed-out’ options, unsure as to why they’re not working…

The inimitable Stephen Arnold concluded the evening with a realistic treatment of the current fashion for ‘real-time’ search. His point was that unless you’re Google, with their fibre-connected, hardware-accelerated gigascale architecture, you’re not going to be able to do real-time web search or anything close to it; on a smaller scale, for financial trading, military and other serious applications you again need to rely on the hardware – so for proper real-time (that means very close to zero latency), your engineering capability, not your software capability is what counts. I’m inclined to agree – I trained as an electronic engineer and worked on digital audio, back when this was also only possible with clever hardware design. Of course, eventually the commodity hardware gets fast enough to move away from specialised devices, and at this point even the laziest coder can create responsive systems, but we’re far away from that point. Perhaps the marketing departments of some search companies should take note – if you say you can do real-time indexing, we’re not going to believe you.

Thanks again to Tyler Tate and all at TwigKit for continuing to organise and support this excellent event.

1. Price cuts – possibly driven by even harsher competition between Google and Microsoft FAST, I can see prices coming down for packaged enterprise search. Autonomy will probably raise theirs
2. Real time search matures – not just Twitter or Facebook, but real time data from many sources being part of enterprise search results
3. More geolocation-aware search – in the U.K. at least, we’re seeing signs that the source data is finally being freed up, which should make it a lot simpler and cheaper to build location-aware solutions
4. A few less second-tier players in the market – it’s still difficult out there, I’m afraid not every company will survive the next year.

You’re welcome to take any of these with a generous pinch of salt!

I dropped in on the associated conference later, and caught a presentation titled “The Real Time Web: Discovery vs. Search”. Antonio Gulli of Microsoft told us about their new European offices, including one in Soho, that were concentrating on bringing new features to Bing – but the results look very familiar, is Bing doomed to play catch-up? The only ‘real time’ feature he discussed was indexing Twitter, although apparently they’ll soon be indexing Facebook as well. Surely real time encompasses more than these two platforms?

Stephen Arnold gave us his thoughts on what we should mean by ‘real time’, sensibly talking about how the financial services world has been using real time systems for many years. He also injected some notes of caution about how difficult it is to trust information spread amongst peers on social networking sites – here’s a recent case, read further down the page for a great quote from Graham Cluley.

Someone from Endeca (I didn’t catch the name, he was replacing the published speaker) showed us lots of slides of various applications of search, but his theme seemed more about how search can replace traditional databases than about ‘real time’, something I’ve blogged about recently.

We finished with Conrad Wolfram, demonstrating Wolfram Alpha, which isn’t really a search engine but rather a computation engine – it tries to give you a set of answers, rather than a list of possible resources where the answer might be found. Not a lot of ‘real time’ here either.

I’m back on Thursday as part of the closing keynote panel.

From a search engine developer’s point of view there are various things to consider: how quickly new content must become searchable, how to balance this against performance demands and how to rank the results.

A lot of search engine architectures are built on the assumption that indexes won’t need to be updated very often, sacrificing index freshness for search speed, so constantly adding new content is expensive in terms of performance. One approach is to maintain several indexes: a small, fresh one and some older, static ones, with the fresh index periodically being merged into the older static set. Searches must be made across all these indexes of course, with care taken to maintain accurate statistics and thus relevancy ranking.

The question of ranking is also an interesting one: in a ‘real-time’ situation, how should we present the results – does ‘more recent’ always trump ‘more relevant’? As always, a combination of both is probably the best default approach, with an option available to the user to choose one or the other.

In any case there will always be some delay between content being published and being searchable – the trick is to keep this to the minimum, so it appears as ‘real-time’ as possible.