Simulating a City

Posted on May 6, 2012 by crista

For the past 4 years or so, in my spare time, I have been working with a small start-up company, Encitra, whose goal is to help cities and real estate developers make sustainable urban plans come to life in the minds and hearts of stakeholders and the general public. We go at it with virtual reality. Not just computer animation movies; we develop complete multi-user interactive virtual environments that are built and re-built over time by multiple people, and that simulate urban areas — both structural and dynamic aspects — as faithfully as possible. Recently, we accomplished an important milestone: we were able to simulate an area of 3km x 1.5km of the city of Uppsala, Sweden. This includes the actual terrain, the major landmarks of the city, several hundred assorted buildings, as well as traffic and pedestrians. It’s all live and accessible on the Internet, although not on the Web browser. This post explains the technology behind it. For the most part, it’s all based on open source software!

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Posted in simulation, social software systems | Tagged , | 3 Comments

The Single Most Important Thing

Posted on March 25, 2012 by crista

What is the single most important feature of a programming system without which you can’t write programs effectively?

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Posted in commentary, social software systems | 1 Comment

Research in Programming Languages

Posted on March 2, 2012 by crista

Is there still research to be done in Programming Languages? This essay touches both on the topic of programming languages and on the nature of research work. I am mostly concerned in analyzing this question in the context of Academia, i.e. within the expectations of academic programs and research funding agencies that support research work in the STEM disciplines (Science, Technology, Engineering, and Mathematics). This is not the only possible perspective, but it is the one I am taking here.

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Posted in academia, research | Tagged | 104 Comments

To Dish or Not To Dish

Posted on February 27, 2012 by abby

Dear @bby,

I am being asked to write a recommendation letter for someone who has been working with me for 3 years and who I think sucks. What should I do? Should I simply decline to do it? Or should I say what I honestly think about that person and his work? — because he deserves it!

Sincerely, Conflicted Recommender

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Ethics in Economics

Posted on November 1, 2011 by crista

Imagine this. You have a brilliant idea for how to reverse the effects of aging in female infertility, a wonderful combination of drugs that you have been developing in your lab with your graduate students, and that will open the possibility of motherhood to hundreds of thousands of women who waited just too long to conceive. You have done your Math, your Chemistry, you have developed the model explaining why your idea works. You have tested it in mice. You have tested it in pigs. You got 90% success. You have very little doubt that it works in humans too. If only you could test it… Now imagine that this is 1925, there are no Institutional Review Boards, no Ethics committees to go through, no clinical protocols. In order to test your ideas, you simply need to recruit women who routinely come to your medical office lamenting that they would like to have children but they are too old to conceive. You wholeheartedly believe in your cure and dream with the Nobel prize. Those women desperation is a powerful context for testing your ideas; they want it, they will gladly try anything!

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Posted in academia, commentary, ethics | 2 Comments

Producing SPLASH

Posted on October 22, 2011 by crista

 

 

I’m chairing SPLASH/OOPSLA this year. That means that I’m like a Producer, I get to do all the work behind the scenes in order to make the conference come to life. And it’s finally coming to life. After one year and a half of “programming,” I just pressed “Run.” It’s a little crazy if you believe in agile. A whole year and a half of designing and “programming,” with no testing whatsoever, no small chunks, just a long process of envisioning, estimating, guessing, coordinating, signing contracts, making decisions; then we unleash the event during 5 days over almost 600 people and hope for the best!

So what’s involved in producing a conference like SPLASH? Read on if you want to know.

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A Theory of Aspects as Latent Topics

Posted on September 17, 2011 by crista

Underlying the work on Aspect-Oriented Programming (AOP) there is a premise that no one ever challenged: the existence of cross-cutting concerns that find their way to programs in a tangled and scattered manner. We’ve all seen it. But do tangling and scattering of program concerns really exist in real programs? Do they have a strong effect or is this one of those academic non-issues? That was the question we set out to answer in a paper we published at OOPSLA 2008. And the answer was: yes, these effects do exist in real programs, they are noticeable and detectable, and they reveal a few insights on the nature of those concerns. But they raise even more questions for AOP. Here is a summary of our study. For all the details, read the paper [1].

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Vandalism Detection in Wikipedia

Posted on September 15, 2011 by crista

If you have to develop a classifier for detecting vandalism in Wikipedia with just a small number of features, what kind of features give the best results? According to our latest work on vandalism detection in Wikipedia, to be presented at WikiSym 2011, the best features are the ones pertaining to user behavior within the system — things like the deletion of other users’ content, the survivability of the user’s additions, number of words deleted by a user, whether the user has a page on Wikipedia or not, etc. Other kinds of features such as textual and language model features are routinely used in email spam filters, but it turns out that these don’t do as well as the user behavior features. That’s right, the user behavior within these systems contains a very strong signal for detecting what the users are capable of doing in the future, and therefore can detect vandalism fairly well, especially the more subtle kinds of vandalism. I’ve been wanting to write an overview of this work for a long time, finally here it is. For all the details, read the paper.

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File cloning in open source: the good, the bad and the ugly

Posted on September 14, 2011 by crista

How much copying is there in open source projects? According to our recent study soon to be presented at ICSM 2011, more than 10% of files found in open source Java projects are clones of other files. That is a lot. But those clones are only in about 15% of projects, meaning that 85% of projects don’t have clones. And, it turns out, some cloning out there is relatively harmless, but we found some uglies too. Here’s a summary of our analysis of what’s going on with these clones. For the complete details, read the paper.

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Graduate School Application Dos and Don'ts

Posted on September 5, 2011 by crista

It’s the beginning of a new academic year. With it, there comes  a new wave of inquiries about applying to UCI/ICS graduate programs and joining my research group. I’ve seen these waves every year for the past 9 years. The vast majority of these inquiries don’t pass my mental spam filter; a small percentage does; an even smaller percentage ends up being accepted. I thought I’d write down my thoughts on these inquiries. I know that amongst the hordes of applicants who fail to cause a good impression on prospective advisors, there are a few bright ones to whom that happens because of unawareness and bad advice. This post is for them. If they find it.

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