Monday, March 12, 2012

The MediaEval Workshop: What it's meant to be and why you want to be there.

The MediaEval workshop is the event held each year in the fall at the culmination of the yearly benchmarking cycle. At the time of the MediaEval workshop many things have already happened in the benchmarking year: The task organizers have worked hard to define tasks and issue data sets. Participants have worked hard to develop algorithms that tackle the tasks, and they have run these algorithms on the data sets. The "runs" have been evaluated and each participating team has written their working notes paper. Now it's time for the workshop!

This blog post provides a view (from my perspective as one of the MediaEval co-ordinators) on the history of the workshop and on what the workshop is meant to be. In particular, it highlights the similarities and differences with other types of workshops.

The main goal of the MediaEval workshop is to bring everyone who carried MediaEval tasks together in one physical location to present and discuss their results, exchange experiences and develop ideas for how to improve their algorithms. The first year that we met at a medieval convent, Santa Croce in Fossabanda, it was mostly due to delight in the wordplay between medieval and MediaEval. However, we soon came to appreciate how getting everyone together working, eating and basically living in the same space creates an extremely productive focus on our our common tasks and goals. (Although unlike the nuns of the Middle Ages we don't go dashing off to prayer when we hear the convent bell.)

In 2010, we held the MediaEval workshop just before ACM Multimedia 2010, which was held at the Palazzo dei Congressi in Firenze, Italy. Santa Croce in Fossabanda is located in Pisa, about an hour's train ride from Firenze. We chose the dates and place to cut down on travel time and cost for people who wanted to attend both ACM Multimedia 2010 and the MediaEval 2010 workshop.

The next year, Interspeech 2011 came to the Palazzo dei Congressi in Firenze about the same time of year. MediaEval submitted a proposal and was granted the status of an "Official Satellite Event of Interspeech 2011". Now, instead of just taken advantage of the convenience for travel, we began emphasize hook-up to the topic of the conference: being associated with Interspeech reinforced the use of speech within MediaEval and helped us to better realize the goals expressed in the MediaEval slogan The "multi" in multimedia.

This year, the 12th European Conference on Computer Vision (ECCV 2012) will be held in Firenze. This conference provides us with the opportunity to reinforce the use of visual content within MediaEval, another of the multimedia "multi's". The MediaEval 2012 Workshop will be held right before this conference starts, again in Santa Croce in Fossabanda in Pisa. A very close contending idea for the MediaEval 2012 workshop was to hold it near 13th International Society for Music Information Retrieval Conference (ISMIR 2012) in Porto. However, the results of the MediaEval 2012 survey showed that the majority preferred to co-ordinate the date and place with ECCV 2012 and stay for a third year in Pisa.

In sum, the idea of being close to a large conference related to MediaEval topics has grown from being a convenience to being an aspect that strengthens and enriches both the benchmark and the workshop.

What exactly happens at the MediaEval workshop? The workshop consists of a series of sessions on the individual tasks. The task organizers present the task as a whole and each team presents its individual results, after which the floor is opened for discussion. More discussion and exchange occurs during meals and breaks in ad hoc groups. We try to build in a lot of space for discussion into the workshop schedule and especially try to create opportunities for students to discuss with more experienced researchers who help them to guide their efforts along the most effective path.

The proceedings are an important aspect of the workshop. The MediaEval workshop proceedings is a "Working Notes Proceedings" and consists of short (two page) papers written by the participating teams to report their results. These papers describe the algorithms that are used and present the results. They then also seek to understand the algorithm, and participants are requested to report:
  • which cases are easy/difficult and why
  • which approaches work best and why
  • which approaches do not work well
The working notes submissions are reviewed by the task organizers. The task organizers may either accept the submission as is, or may come back to the participant team with a request for revisions of the paper. The preferred mechanism is to have the papers revised rather than to reject them --- sometimes this revision cycle means that the working notes proceedings is not ready until just before the workshop. For this reason, the working notes proceedings is distributed at the workshop on a memory stick.

After the workshop, the working notes is made available online. The 2011 the "Working Notes Proceedings of the MediaEval 2011 Workshop" was published here: and in the future we would like to continue to use By publishing in this way, the copyright for the individual papers is with the papers' authors.

MediaEval working notes papers are intended to be first versions of work that is later extended by the authors and submitted to mainstream venues, such as conferences and journals. The fact that the MediaEval workshop proceedings consists of short working notes and that the copyright does stays with the authors keep the proceedings consistent with the goal of reporting an initial research result, which will then be refined and extended using input from the discussion at the MediaEval workshop.

Another important goal of the workshop is to discuss the tasks themselves. Did they help to move the state-of-the-art forward? Should we improve or replace them next year? Are their new questions that need to be answered that require new tasks. Any one attending the workshop is welcome to stand up in the final session and "pitch" an idea for a new task. Tasks which receive good community support in this session have a good chance of receiving the response levels they need on the yearly MediaEval survey to run as tasks in the next year.

Finally, the workshop also aims to connect ourselves and our research to the larger community. We welcome participants from industry who have tasks that they might want to pitch to the community. We also welcome representatives from other benchmarks: MediaEval grows stronger by staying in close contact with groups running benchmarking activities in areas beyond the MediaEval core domain of human and social multimedia. MediaEval 2011 was presented at CLEF 2011, NTCIR 2011 and FIRE 2011 and in 2012 we hope to convince some of our sister benchmarks to give a reciprocal presentation on their own experiences.

As part of staying connected to the larger community, the MediaEval 2011 workshop included a poster and demo session where projects that help to organize MediaEval tasks could present their results and where industry people could make a presentation of new and interesting problems that they would like to make known to the MediaEval community as possible benchmarking tasks.

The workshop closes with a gathering of task organizers and others who have invested time and effort into the community or want to get more closely involved in the future. During this session, we reflect back on what happened so far in the benchmarking year and also discuss the MediaEval related activities that we organize beyond the core benchmarking activities. These include joint papers among all the participants of a task and also special sessions at conferences. Looking forward we also plan to get involved in organizing more workshops (of the traditional variety) at conferences and also think about the possibilities of special issues. Finally, we reflect on our MediaEval goal, To offer the community innovative new tasks related to the human and social aspects of multimedia and our slogan The "multi" in multimedia (it not necessary to be able to say the slogan with a straight face.) On the basis of these reflections, we consider where we would like to go with the benchmark in the coming year.

So why do you want to be at the MediaEval workshop? Well, if you are a task participant, it gives you an opportunity to exchange with other people working on topics similar to yours and helps you to understand and improve the algorithms that you are using to approach your task. MediaEval needs a central group of dedicated researchers to organize the tasks that make the benchmark run. Attending the workshop is a good first step to getting more deeply involved in MediaEval, for example, by proposing a task for the year.

On the MediaEval 2012 survey, we had a question concerning what the community thinks about how MediaEval should grow. I personally, want to keep the workshop as small and intimate as possible. In 2011, we had nearly 60 people and that appeared to me to be a good maximum size for the workshop. However, when I examined the survey results, I realize that I am in the minority here, and that most of the people in the community would like growth. As a result, I am changing my opinion and we will not attempt to artificially restrict growth, as long as it is sustainable.

The issues and ideas around growth is just one area in which the concept of the MediaEval workshop is evolving. One of MediaEval's strengths is that it develops from year to year, guided by the input of the community --- and in particular those people who invest the most hours of their time to make it work. I look forward witnessing and being involved in this development in the 2012 season and, we hope, to seasons beyond.

For further impressions of the MediaEval workshop, check out the MediaEval 2011 workshop video:

Saturday, March 10, 2012

Querying the Collective: Why search engines should (responsibly!) support analytics

My thoughts today turned towards the social responsibility of search engines. As search improves, it seems that the question is not moving towards being resolved, but rather is becoming more important. Simply put, as the helpfulness that search engines have in our lives increases, so does their power over us. In this post, I'd like to attempt to unpack that thought a bit and build a case for the importance of social responsibility of search engines.

Let's consider the question of the identity of the entity with which knowledge resides. In other words, let's have a look at, "who knows what" in some basic search scenarios. User information needs, I claim, differ along the who-knows-what dimension:
  • Known-item search: "I know what I want and my information need will be fulfilled when I can get my hands on this item." (Knowledge effectively already with me.)
  • Ad hoc search: "I don't know exactly what I want. But I know that there are other people who know. My information need will be fulfilled when I can get my hands on information sources created by people who do know." (Knowledge with other people, soon to be with me.)

As long as we stick to these two variants, the world is relatively well behaved. Social responsibility arguably remains with the searcher and with the individuals making the information sources available.

However, with the next step in this typology, things definitely become different.

  • Analytics search: "I don't know exactly what I want. In fact, I know that there is no individual person who knows. My information need will be fulfilled if I can get my hands on information that is created using analytics over a larger number of information sources." (Knowledge with no one, not yet.)

We do analytics search all the time, even without realizing it. For me, it's often for small things while writing research papers, for example, for finding the more common usage "crowd-sourcing" vs. "crowdsourcing" or to see if "internet" has finally overtaken "Internet". I actually just this moment carried out a search for "analytics", which is being red-underlined as a spelling mistake as I write. In response to my query, Google tells me "About 117,000,000 results (0.24 seconds)". I decide that there are a lot of other people using this word -- many in the same way that I am using it now, so I ignore the spellchecker and move on.

The point is that this 117,000,000 is information that was derived on the spot by analyzing and aggregating a huge number of data sources. As a result, the responsibility for this information has shifted and now lies elsewhere. It is not so clear that it lies only with me, the person asking the question, or with the information sources that are being aggregated. Rather, the responsible for creating this information lies with the algorithm that made the calculation. If we think that a non-human entity such as an algorithm cannot be responsible, then the conclusion must be that the responsibility lies with the people who created and control the algorithm that made the calculation, i.e., the minds and masters behind the search engine.

Of course, many times that responsibility is not a particularly heavy weight and the answers to analytics search queries can often be wildly off and still not be harmful. Give or take a million, I still will see that there are a lot of people using the word "analytics" and that answers my question.

However, I would argue that there are enough cases in which the results of analytics search queries have a large enough impact that they should force us to think carefully about the social responsibility that is borne directly by our search algorithms, their creators and the providers of our search services.

Recently, I spent some time in a house by a lake in the forest. The local news reported an incident in which a hunter reported a man in the forest, carrying a gun, but not wearing the blaze-orange of a hunter. The man had fired at him, and the hunter returned fire. Basically, I made my decision about when to go out of the house after hearing that news report by using a search engine to monitor real-time media (Twitter and local news). My queries were analytics queries because they relied on the entire collection of available information being scanned. My conclusion about the situation relied on a relatively subtle difference between no one mentioning it and it being mentioned by a handful of people (the forest being rather sparsely populated). I continued periodic query sessions, and the story died out relatively quickly. I walked out of the house with confidence that the incident was a fluke and not a rampage and that no one was going to take a pot shot at me.

One could argue that I was irresponsible for potentially putting my safety in the hands of a search engine. But one could also argue that I was irresponsible for being there in the hunting season. There are also those that would claim that the place is a bit weird anyhow, and should be completely avoided. The problem is, that place is where I'm from. I'm probably not about to stop going back and also I'm probably not about to stop looking for information by carrying out analytics search with a search engine.

It seems inevitable: People use analytics search to form opinions and make assessments that influence their behavior and lead them to make important decisions.

We have little choice but to admit that we would like search engines to offer us as users the possibility to satisfy our information needs using analytic search. It gives us a lens to view the world around us. It takes us a step in the direction pointed to recently by Doug Oard, who was quoted on Twitter as wanting an information retrieval system that is an exoskeleton for the mind. Personally, (and to the bemusement of my colleagues) I tend to talk about search, especially in the context of social networks, as providing us with a prosthesis. In the end, all the metaphors boil down to analytics search being just plain important to us and to what we want to do in our lives.

We are left with the conclusion: Search engines should support analytics search, but they should take careful regard of social responsibility.

Why am I thinking of analytics search today? Probably because I've come up against another problem where it is useful. This problem involves no guns, so it's not particularly life threatening -- at the most it threatens the productivity of our lab.

At the beginning of the year, there was a high-level decision to restrict access to our building on the weekends. The cited reasons were that ICT technology no longer requires 24-hour building access and that weekend closure would save energy and security costs. The net result has been that on the weekends our lab is completely empty, when there used to be at least one or two PhD students working there, when I'd go in.

I became curious about exactly how much electricity is being saved and realized that we can actually make a rough estimate using social media to calculate the number of weekends in which the building is actually powered down. For example, today (a Saturday) it wasn't. Today, I took a picture (above) in the cafeteria which reveals the fact that it wasn't. There were also other people in this group in the picture that were themselves taking pictures. If a search engine will allow me to find other pictures (e.g., on Flickr) of weekend events in the building, it will be possible to make an estimate the total number of days of electrical consumption actually saved by keeping the PhD students out of the lab.

None of the individual picture takers know this information, but if the information can be aggregated with the support of a search, then we can know -- calling the information into being, as it were, using a couple of queries linked to dates and locations. I'll leave it to another day to examine the question of if I actually have a right to know how much energy is being saved by the building closure policy. Here, I draw a different conclusion: if I am going to rely on a search engine to formulate an impression of what happens in the building on the weekends, then I would like that search engine to have assumed the responsibility of giving the best answer it possibly can.