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For this week's TWIST (This week in infrastructure systems) post, I want to do things just a bit differently and focus on a topic that is crucial for any infrastructure system: uncertainty framing.

Of course, it is very difficult to agree on how to define uncertainty, and once it's defined, it can be difficult to select robust tools for managing the types of uncertainties we see in infrastructure systems. Since infrastructures are characterized by long life cycles, large geographic and demographic scope, and substantial interconnections within and between lifeline systems, one wonders how any problems are selected for analysis. The web of intricacies faced by analysts and policy makers can be intractable, and the ways that the unknowns influence the likelihoods of the possible consequences makes every choice high-stakes. Some professionals call these problems "wicked," and prefer to "muddle-through" them, take a garbage can approach, or just admit that optimal solutions are probably not possible and accept the best feasible option--to our knowledge--at the time. Others call these "deep uncertainties" and even wonder whether resilience analysis is more appropriate than risk analysis for infrastructure systems.

However you choose to sort all that out, this issue is of critical importance to infrastructure enthusiasts today. In the US, we face a crisis of governance, in which the public trusts neither government nor experts, the center no longer holds--making it impossible to provide legislative/political stability for public engagement over the scientific debates, and our most important issues are fraught with uncertainties that make it impossible to provide an unequivocally recommended course of action. Of course, infrastructure is impossible without both strong governance and strong science (or trans-science, if you prefer). With that in mind, two articles stood out from Water Resources Research this week:

  • Rival Framings: A Framework for Discovering how Problem Formulation Uncertainties Shape Risk Management Tradeoffs in Water Resources Systems. In this paper, Quinn et al. explore how rival problem (read: uncertainty) framing could lead to unintended consequences as a result of inherent bias in the selected formulation. Of course, this is unavoidable for even modest problems in critical infrastructure systems, and so they provide some guidance for carefully exploring the possible consequences that can be foreseen under alternative problem formulations.
  • Towards best practice framing of uncertainty in scientific publications: a review of Water Resources Research abstracts. In this paper, Guillaume et al. describe how awareness of uncertainty is addressed within WRR abstracts/papers. They develop an uncertainty framing taxonomy that is responsive to five core questions: "Is the conclusion ready to be used?"; "What limitations are there on how the conclusion can be used?"; "How certain is the author that the conclusion is true?"; "How thoroughly has the issue been examined?"; and, "Is the conclusion consistent with the reader’s prior knowledge?". Of course, as the authors acknowledge, the study of uncertainty framing is inter-disciplinary, and achieving an uncertainty framing that is responsive to these questions is an art in itself.

Uncertainty, to me, is both fearsome and beautiful. I hope these two articles, or some of the other links shared, provide some useful thoughts for managing uncertainty in your own study or management of infrastructure systems.

It has been quite a while, but I'm back to share something I'm listening to now and want you all to hear. It is a podcast of this past Monday's Dianne Rehm Show titled "Using Design Theory to Build a Better Life." You can get it [here] or [.mp3 here].

Just to get you started, here's a paraphrase from early on: "if 8 out of 10 students here at Stanford answer 'I don't know' as their greatest passion, we need to think of a different approach to counseling students concerning career decisions. We believe that a passion is the end of a life well-lived, not where you start..." [As I said, this is a paraphrase, and is not exact. Go listen to the tape!]

I really hope you will listen to these two former Apple engineers' conversation with Ms. Rehm. It is exciting and insightful, especially for those of us who belive design is one of the defining dimensions of the human life.

Peace and Blessings to you all.

 

Herb Simon's book, The Sciences of the Artificial, has instantly become one of the more indispensable books on my shelf. Even though I spent five years across the quad from a building with his name on it, I never really learned what he did or why his work was so important. So it is with a bit of embarrassment that I admit this book was an unexpected pleasure.

I stumbled across Simon's book as an accident. One of my students recommended we read Ethiraj and Levinthal's "Modularity and Innovation in Complex Systems" to inform our discussion about information sharing in support of infrastructure system emergency preparedness. One of their references to "The Architecture of Complexity" seemed interesting, and I wanted to learn more about system architecture so I could understand what one of my newest colleagues, David Broniatowski, was saying when he discussed the role of architecture in system flexibility and controllability. So I set out in search of "Architecture of Complexity," and the librarian instead pointed me to The Sciences of the Artificial. What a blessing!

I truly want you to read the book, so I won't say too much. For me, my most cherished insight from Simon was the following:

A man [An ant], viewed as a behaving system, is quite simple. The apparent complexity of his behavior over time is largely a reflection of the complexity of the environment in which he [it] finds himself [itself].

To me, the simplicity and elegance of this hypothesis characterizes the entire book. Although we may disagree on the specific mechanisms, or on the plausibility of this hypothesis, its influence on the practice of engineering and policy design cannot be doubted. I also see the practical results of exploration of this hypothesis everywhere I look in research and technical literature. This hypothesis and many other insights (e.g., satisficing, hierarchical organization of complex systems, valuing the search vs. valuing the outcome, etc.) immediately resonated with my experiences and pulled me all the way through the book.

Because I was trained as a civil engineer, it has taken a decade after my undergraduate to encounter Simon's work. I believe I can say that it has been worth the wait.

At this year's European Safety and Reliability Association (ESRA) annual meeting, ESREL 2013, Dr. Francis presented a discussion paper co-authored with GW EMSE Ph.D. student Behailu Bekera on the potential for using an entropy-weighted resilience metric for prioritizing risk mitigation investments under deep uncertainty.

The goal of this metric is to build upon tools such as info-gap decision theory, robust decision making approaches, scenario and portfolio analysis, and modeling to generate alternatives in order to develop resilience metrics that account for a couple ideas.  First, we felt that if an event is very extreme, it would be quite difficult to prepare for that event whether or not the event was correctly predicted.  Thus, resilience should be "discounted" by the extremeness of the event.  Second, we felt that if an event is characterized by an uncertainty distribution obtained through expert judgment, the degree to which the experts disagree should also "discount" the resilience score.  In our paper, the goal was to present the entropy-weighted metric we'd developed in our RESS article to the ESREL audience in order to engender some discussion about how to evaluate resilience under these conditions.  This work was inspired by a talk Dr. Francis attended by Woody Epstein of Scandpower Japan in PSAM11/ESREL12 Helsinki.

The paper and short slides now appear on the publications page of the SEED research blog.