Congratulations to Masood Jabarnejad for winning the Interactive Session on Monday with his poster "Operations Research to Reduce the Cost of Electricity."

Congratulations to Yuanhui Zhang for winning the Interactive Session on Tuesday with her poster "Optimization of Treatment Decisions for Chronic Diseases: An Application to Type 2 Diabetes."

The main objective for care of type 2 diabetes is to control the patient's blood sugar level to reduce the risk of developing health complications. Uncertainty in the progression of the patient's blood sugar level, and medications' effect and side effects make the treatment decisions challenging. We developed a Markov decision model to optimize the sequence and timing to initiate hyperglycemia lowering medications to maximize the patient's quality of life. The model-based results can be used to help physicians make treatment decisions and also provide scientific evidence to help policy makers make treatment guidelines.

If you miss the Wagner presentations, no problem! In just a few weeks, INFORMS will offer meeting attendees and all members a chance to see these presentations on demand via the Web. Watch for our announcement or check the INFORMS Video Learning Center.

9am-3pm, Hilton, Grand Ballroom
On-site interviews to explore opportunities in academia, industry, and government take place today. Good luck to all!

By Andrea Hupman
Dimitris Bertsimas won the Philip McCord Morse lectureship award in 2013. The award is bestowed in honor of its namesake, a pioneer in the field of operations research and management science who was devoted to the field. Dr. Bertsimas embodies the ideals and spirit of Professor Morse. Dr. Bertsimas began the lecture with a tribute to Professor Morse, describing him as a personal hero and describing how he was inspired by Professor Morse's books.

Dr. Bertsimas illustrated how mixed-integer optimization (MIO) has improved in the last few decades. From 1991 to 2013, the speedup for solving MIO problems has been 580,000 times. A MIO that would have taken seven years to solve 20 years ago can now be solved on the same 20-year-old computer in less than a second. In that time, the speedup in hardware has been 320,000 times. Taken together, these advances represent a total speedup in solving MIO problems of 200 billion times.

Motivated by these new capabilities, Dr. Bertsimas discussed a heuristic approach to the best subset problem that uses MIO with a warm-start. With this approach, it is possible to reach an optimal solution very quickly although you may not know for sure that it is optimal at that time. As a heuristic, however, it works very well, with results that match optimal most of the time.

In the second part of the talk, Dr. Bertsimas discussed using an algorithm to build regression models. In evaluating the approach, it is difficult to compare to existing approaches due to the role of human judgment in creating regression models. The algorithm, however, is shown to have results that are similar to existing methods, but better in some measures such as sparsity.

Dr. Bertsimas concluded the lecture by questioning how we define tractability. He gave the following definition: a problem is tractable if it can be solved for sizes and in times that are appropriate for the application. By this definition, problems that were previously intractable become tractable, expanding the horizons of what is possible in operations research.

By Tengjiao Xiao
The IFORS Distinguished Lecture was given by Dr. Lyn Thomas from University of Southampton. The lecture was both insightful and interesting. Dr. Thomas first introduced the history of credit scoring, which uses operations research and statistical models to assess default risk, for consumer lending. The fact that San Francisco is the birth place of credit scoring is a happy coincidence. Among the different approaches have been used in credit scoring, logistic regression is the most common one being used now. Besides logistic regression, classification trees and ensemble models are currently in use as well. Read More.

By Andrea Hupman
Ali Abbas chaired a technical session on recent advances in utility theory. He began by posing the question of whether it is true that the multi-attribute utility can always be represented as a function of individual (single-attribute) utility functions. And the answer to the question is that it doesn't have to be.

Currently, most applications of utility theory make the assumption that the decision maker's preferences satisfy mutual utility independence. This assumption allows preferences under uncertainty to be modeled with two simple functions - the multiplicative and the additive utility function - that combine single-attribute utility functions to create a multi-attribute function. However, there is a danger in making such assumption arbitrarily. It is shown through simulation that assuming properties of utility independence when it does not hold can result in up to 25% of decisions being incorrect. This result is compared to a coin toss, in which 50% of decisions are incorrect without any analysis.

The class of utility functions that satisfy additive ordinal preferences is broader than those satisfying mutual utility independence. Dr. Abbas derived the most general functional form of these utility functions and showed that it is an Archimedean copula. This copula allows the marginal utility functions (i.e., the single-attribute utility functions) to remain constant while a parameter that governs the tradeoffs among the attributes is varied. Thus, the single-attribute preferences can remain constant while preferences for tradeoffs among the attributes can be adjusted to match the specific preferences of the decision maker.

This session highlighted that new advances in utility theory are opening exciting new opportunities for both research and practice in decision analysis.

All attendees receive free access to the INFORMS 2014 TutORials in OperationsResearch: Bridging Data and Decisions online content concurrently with the meeting. Registrants of the 2014 INFORMS Annual Meeting have online access to the 2014 chapters, written by select presenters, beginning on November 1, 2014. Access this content using the link provided to all attendees by email or, if you are a 2014 member, simply login to INFORMS PubsOnLine. 

Program Book Kiosks
In an extended effort to go green, this year we are introducing kiosks to access a flip book of the full conference program. Two kiosks will be located in the Exhibit Hall and one kiosk will be located near the INFORMS Registration Desk in Yosemite BC.