The University of Arizona
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Todd A. Proebsting

Professor and Department Head
Office: Gould-Simpson 746
Phone: 621-4324 (Note: I check voicemail semiannually.)
Fax: 621-4246

Recent History

Before coming to the University of Arizona in August 2012, I was at Microsoft for 15 years. I was a founding member of Microsoft's cloud computing project, which ultimately became Windows Azure.

In 2003 at Microsoft, I founded Microsoft's efforts in using prediction markets to help forecast future events. This ultimately led to markets that successfully predicted a huge delay in a major product.


I am very interested in cloud computing. Cloud computing enables people to harness the power of networked resources productively. Cloud computing platforms can overcome the inherent complexities of large-scale processing done on commodity hardware, allowing applications to scale elastically and reliably. My interest is in finding ways to make these resources even more accessible to programmers.

I am also interested in programmer productivity in general. I am dismayed at the current state of programming tools (e.g. programming languages, development environments, static analysis tools) and I think we can do much better. My primary focus here is investigating how to get rid of all the clutter in most statically-checked computer programs without sacrificing the benefits of static analysis.

Finally, my efforts in deploying prediction markets at Microsoft has made me very interested in information aggregation and incentives. How do we elicit information from people (or machines), and aggregate it in a way that rewards good information sources?


In Spring 2015,, I am teaching CSC 352: Unix and Systems Programming .


I may be best known for "Proebsting's Law", which asserts that compiler optimizations have yielded annual performance gains an order of magnitude worse than hardware performance gains. The law probably would have gone unnoticed had it not been for the protests by those receiving funds to do compiler optimization research.

I am also known for "Proebsting's Paradox", which is an unexpected result in a provably optimal gambling strategy. Unlike Proebsting's Law, I did not name this one after myself, but rather Dr. Ed Thorp (of Beat The Dealer fame) named it after me. (See Wikipedia for details.)

Amused at the ridiculousness of having things named after myself, I was hoping for "Proebsting's Folly", where I was going to convince the United States Government to buy the sovereign nation of Iceland to get them out of their banking troubles a few years ago. (This was based on the premise that every US purchase of a really cold territory is a "folly".) Unfortunately (for me), Iceland was able to recover.