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IBM IR Seminar Highlights (part 1)

IBM Haifa Research LabsYesterday’s seminar was also packed with some very interesting talks from a wide range of social aspects to IR and NLP.

Mor Naaman of Rutgers University and formerly at Yahoo! Research gave an excellent talk on using social inputs to improve the experience of multimedia search. The general theme was about discovering metadata for a given multimedia concept from web 2.0 sites, then using those to cluster potential results and choose representative ones.

In one application, this approach was used to identify “representative” photos of a certain landmark, say the Golden Gate bridge, see WorldExplorer for an illustration. So first, you’d find all flickr photos geotagged and/or fickr-tagged by the location and name of the bridge (or any given landmark). Next, image processing (SIFT)  is applied to those images to cluster them into subsets that are likely to be of the same section and/or perspective of the bridge. Finally, relations between the images in each cluster are formed based on the visual relation, and link analysis is employed to find a “canonical view”. The result is what we see on the right sidebar in World Explorer, and described in this WWW’08 paper.

[Update: Mor commented that the content-based analysis part is not yet deployed in World Explorer. Thanks Mor!]

tagmaps1

Another example applied this approach to concerts on YouTube, and the purpose was to find good clips of the concert itself, rather than videos discussing it etc. Metadata describing the event (say, an Iron Maiden concert) was collected from both YouTube and sites such as Upcoming.org, and Audio Fingerprinting was employed to detect overlapping video sections, as it’s quite likely the concert itself would have the most overlap. Note that in both cases, the image/audio processing is a heavy task, and applying it only to a small subset filtered by social tags makes the work involved more feasible.

I’ll talk about the keynote (by Prof. Ben Schneiderman) on another post, this one is already way too long… Here are soundbites from some other talks:

Emil Ismalon of Collarity referred to personalized search (e.g. Google’s) as a form of overfitting, not letting me learn anything new as it trains itself only on my own history. That, of course, as a motivation for community-based personalization. 

Ido Guy of IBM talked about research they did comparing social network extracted from public and private sources. The bottom line is that some forms of social relations are stronger, representing collaboration (working on projects together, co-authoring papers or patents), and others are weaker, being more around the socializing activities (friending/following on SN, commenting on blogs etc) . Of course, that would be relevant for Enterprise social graph, not necessarily personal life…

Daphne Raban of Haifa University summarized her (empirical) research into motivations of participants in Q&A sites. The main bottom lines were: 1) money was less important to people who participate very often, but it’s a catalyst, 2) Being awarded with gratitude and conversation is the main factor driving people to become more frequent participants, and 3) in quality comparison, paid results ranked highest, free community results (Yahoo! Answers) ranked close, and unpaid single experts ranked lowest.

IBM IR seminar talk on Socially Connected Search

I had the pleasure today of presenting Delver in a talk I gave at IBM Haifa Research Labs IR  seminar. My slides are over here.

The seminar’s focus this year was on social search, and there were quite a few other talks I found very interesting, I’ll blog about those later on too. One of the positive surprises for me was the amount of work carried out at IBM-HRL on social/web 2.0 tools such as SONAR. Impressive social product work for a non-consumer player; I plan to read more of their published work on that.

OpenID needs a killer-app

openid_big_logo_textThe OpenID community is buzzing with board elections coming up next week. With Facebook and Google drawing attention with their simultaneous recycling of old news (MySpace’s PR person should have been fired long ago for being so bluntly left out), there is growing concern in that community for the future relevance of an open, rather than a commercially controlled, identity. Dave Winer thinks the commercialists will kill it by over-complexity. Chris Messina believes that better usability and branding could jumpstart OpenID. 

Personally I see no reason right now why Facebook won’t pull it off. The main reason is that they have a full turnkey system in-place. As a publisher, I don’t need to adopt an OpenID library, access a few Contacts APIs (standards are still only making baby steps) and then integrate some form of postback to an aggregator. Facebook gives me the whole monty, on a very large network provider, and a simple WordPress plugin can do all that work.

That’s where an open community lags behind a concentrated commercial effort – tying it all together to a killer-app. An open content platform? well, that was boringly nice, until someone connected it to a killer-app need of an anyone-can-edit-encyclopedia and suddenly everyone’s using wikis. Firefox did not become popular because it’s open, but rather because its openness allowed open features, such as greasemonkeying and tons of extensions. Where is the OpenID equivalent? 

Personally I think blog widgets, and in particular commenting platforms, can be exactly it. The blogosphere is decentralized enough for an open product to compete fairly against Facebook’s push. There are already commercial products making use of it, such as Disqus. Now just decentralize that too, and let every OpenID user assemble their own Disqus page from an OpenID-based commenting plug-in. If you don’t like that, find another potential killer-app (David Recordon’s browser-based identity has good potential too), just don’t assume that an open technology alone makes any difference to anyone beyond the techies.

If you liked my blog, you’d like this post. Trust me!

One of the sites that most impressed me when I first started browsing the web was called MovieCritic.com. You would rate a few movies you saw, then it would predict whether you’d like a new movie. It would even let you find one that matches both your taste and your girlfriend’s. Pure magic, for that time. For me that was the first demonstration of what we can achieve with the web as a medium.

MovieCritic is dead for a few years now, but recommender systems are now everywhere. NetFlix runs one of the most successful commercial implementations (Amazon another classic example, “People who bought this book…”), and two years ago they challenged researches to come up with a system that would perform 10% better than their own, in predicting users’ ratings. The best achieving team so far almost got there, and today I attended a talk in the Technion by Yehuda Koren, one of the team members and a researcher at Yahoo! Research Haifa lab.

Most methods follow the neighborhood-based model – find an item’s neighbours (in some representation), and predict based on their rating. This may be done in a user-user matching (find users like this user, then check their rating) or item-item (find items like the rated item, then predict based on how the user rated those items). One of the interesting approaches proposed by Koren’s team represented both users and movies in the same space, then looked for similarity in this unified space.

The most striking finding for me, however, was that winning strategies did not use anything from the movie’s “content” features. Genre, director, actors, length, etc. – all these did not produce any additional value beyond the plain statistical analysis and correlation of ratings and users, and are therefore not used at all. In fact, Koren claims that knowing that a certain user is a Tom Hanks fan makes no difference, we will infer this from the recommendations anyway (assuming there are enough of them of course).

I find that almost sad… Not being able to intelligently reason over the underlying logic exposed by an AI software is a tremendous drawback in my eyes, even if the overall prediction score is better. Telling the user “you may want to watch this movie because A and B and C” can benefit in more satisfaction by the user, understanding even the incorrect predictions, and possibly leading to a feedback cycle. Doing away with it is like showing web search results without keyword highlighting, no visible cue for the user why this result was returned (“…trust me, I know what’s the right answer for you!“).

Bootstrapping Social Search

As a followup on Brynn’s review of Delver, I’ve had an interesting exchange with Lachlan Hardy, where Lachlan expressed his disapproval of Delver’s crawling and unifying the social graph (content alone seems ok). My response is in this thread.

The important issue is that socially-connected search requires a comprehensive and unified social graph, which can be quite difficult to achieve. When users conduct their first search, they would expect all of their friends, friends of friends, and their respective content to be pre-indexed, for such a service to be of any use.

Skipping that part makes it impossible to bootstrap, and would be like a web search engine that includes only websites that opted-in to be included in the index, or like a FriendFeed version that shows no public profiles, and if you want to follow someone you must create their consolidated profile yourself. These can be regarded as far more privacy-observing services, but will probably never bootstrap as their real-life counterparts did. It’s all about keeping the balance right.

Oh yes! how true!

Joel Spolsky is back from his podcasts moonlighting and has an angry piece on:

…unbelievable proliferation of anecdotes disguised as science, self-professed experts writing about things they actually know nothing about, and amusing stories disguised as metaphors for how the world works…

I like reading Joel. He’s smart, humorous, and has excellent insights on the software industry. This post, like many others, indeed made me do the Oh-yes!-How-true! routine at first. It reminded me of an anecdote that Mosh, a colleague at work was telling, on how a respected investment bank newsletter was advising him just a few months ago to buy the solid but profitable Icelandic state bonds (luckily he didn’t). Yes, the economic big bang indeed demonstrated how experts may know nothing, at least in that field.

But something bothered me still. Joel went on to tell us that:

On Sunday Dave Winer [partially] defined “great blogging” as “people talking about things they know about, not just expressing opinions about things they are not experts in (nothing wrong with that, of course).” Can we get some more of that, please? Thanks.

I’ve read Dave’s post, and it’s a good one too. But asking myself where this definition put my own blogging, I had to send myself to shamefully stand in the corner, as I did sometimes express opinions about things I’m not an expert in. It was at that point that I realized this elitism stems from simple old school, centralized thinking on journalism. You see, blogging is a many-to-many medium, and you get to pick your reads. If that’s what you want, those sources are there, you just need to find them, Dave Winer mentions counter examples even in that same post.

Elitismo, by duka/Flickr

The new art of this medium, then, is picking those reads, and it’s no less than a skill for life in my eyes. If only my children’s computers teachers would teach them how to choose content sources, how to pick quality over noise, how to evaluate trustworthiness, rather than teaching how to google or use MS Powerpoint, I’d feel a lot more like they’re acquiring a skill for their the-web-is-like-air future life…

Social Search, or Search Socially?

An interesting paper in Computer-Human-Interaction conference CSC08 described social search in terms of the entire searching process, from consulting with friends on what keywords to use, to sharing the search outcome. The research was based on interviews on Mechanical Turk asking for respondents’ recent search experiences, and concluded with some practical suggestions. After watching the presentation slides, I also exchanged some thoughts with one of the authors, Brynn Evans.

MashupAds: the Banner Strikes Back

dapper-logo1A couple of years ago, when I was working on a web 2.0 platform we launched in a previous workplace, we were desperately looking for a simple advertising solution that would boostrap our initial content site revenues. Not wanting to start selling ad space ourselves, we needed some kind of a turnkey solution, but all we could use was the inefficient but simple-to-use AdSense for Content. We had a look at Shopping.com’s API, for which we saw a great implementation in answers.com, but once we dived into the documentation it was clear that the overhead of implementing is huge. So we just gave up and used AdSense.

Text ads are not always the right tool. Banners attract your readers’ attention a lot better, and even give some grace and color to your pages. But we all came to think of banners as irrelevant, annoying “punch the monkey” stuff, and relevant banner designs take costly creative efforts, thus we all let AdSense dominate with a lousy solution for content sites.

So when a friend who works at Dapper told me about MashupAds, which just launched, it instantly sounded like a great idea. Let advertisers stream relevant graphic ads directly from their published content, no need to work on separate creatives (which is a major pain over text ads), and give content startups another turnkey monetization alternative, helping them optimize their targeting by easily specifying the exact hints to use on the page. Dapper’s demos also show the visual advantage of banner ads over text ads in certain cases, but that is, of course, assuming the visual does look good and fits the target site. In fact, I can already guess requests start flowing to Dapper from early adopters – “…can I change the layout of that ad? that pinky background really doesn’t look good on my purple background!”… good luck with that, Avner! 🙂

Solving Checkers

I attended a talk today at the Technion by Jonathan Schaeffer from the University of Alberta in Canada, the person behind Chinook. Chinook is practically the world champion in the game of checkers, if only the world checkers federations would allow computer programs to compete.

Solving checkers, according to Schaeffer, turns out to be much more a laborious process of solving lots of hardware problems, rather than artificial intelligence algorithms. It took 19 years to build a database of board positions sufficiently large to solve from any given position (and there are 5 billion billion such positions, mind you). Since relying on a wrong piece of data could be catastrophic to the complex calculation, there was a lot of dealing with disk failures, network failures, grid calculation. Sounds a lot like running a large-scale search engine, only that search engines can afford to say “Oops…”.

In one case, Schaeffer, who started out in 1989, reached the 32-bit limit in his files. He started refactoring his code and databases to accommodate 64-bit pointer arithmetic, but ended up deciding it’s better to wait 3 more years for 64-bit to become mainstream. So in fact sitting idle for 3 years can do wonders to your projects. In another case, a bug discovered in 2005 was traced back to data created in 1992, which forced a re-calculation of all the data that relied on it. Bummer.

But what I truly found most interesting was the human story behind it all. Chinook’s major opponent was the late Marion Tinsley, world champion and undisputably the best human checkers player ever, who in his career of thousands of games lost only five. Schaeffer tells of hate letters he received after Chinook beat Tinsley, who died shortly after, and of his decision then to prove that a human simply can not beat a machine in the game.

The bottom line? Schaeffer has now indeed proven that the best an opponent of Chinook can achieve is a draw. This positions humans as those who could err and lose. A beautiful definition…

In the footsteps of Napoleon

A while back I made a sweep through some old CDs we had at home to rip them, and rediscovered some old favorites. One of these was Al Stewart’s Roads to Moscow, an epic ballad telling the story of Operation Barbarossa in the eyes of a Russian soldier. Al Stewart tells the story in such a beautiful and captivating way, that I could feel the tragedy for both fighting sides, had my own personal existence not depended on the final outcome. I found myself skipping straight to Wikipedia for more reading, chilling stories of Hubris on both sides, endless ‘almost’ moments, the tragic betrayel by Stalin of his own war heroes, and the inevitable comparison with Napoleon’s accounts:

The Germans were nearing exhaustion, they also began to recall Napoleon’s invasion of Russia. General Günther Blumentritt noted in his diary: “They remembered what happened to Napoleon’s Army. Most of them began to re-read Caulaincourt’s grim account of 1812. That had a weighty influence at this critical time in 1941. I can still see Von Kluge trudging through the mud from his sleeping quarters to his office and standing before the map with Caulaincourt’s book in his hand”

Only later did I consider searching, rather than going straight to Wikipedia. Surprisingly, there were quite a few quality articles in the top 10, so I tried to figure what inhibited my strong search habits. Two reasons came up –

  1. Wikipedia’s mass of editors and strict adherence to NPOV, ensures me I’m not wasting my time on someone’s subjective view
  2. Habit – I knew what coverage and scope to expect in Wikipedia

No wonder, then, that Google got concerned about this habit of visiting adsense-less, top search result pages, tried to tackle it with Google Knol, but failed. But then, revisiting my reason #1 above shows very clearly why the individualist knol concept will always fail against Wikipedia as an objective information source, no matter how much weight Google puts behind it. Someone’s hubris at Google followed in the footsteps of another Napoleon, too.