Here's a quote from a letter in this week's Economist about how to use big
economic models: The root of many problems lies not in the [economic] models themselves but in the way in which they are used. Too often we ask "What will happen?", trapping us into the mug's game of prediction, when the real question should be: "Given that we cannot predict, what is our best move today?"...Instead of determining the "best" model that solves optimal strategies we should instead seek the most "robust" model that achieves a given level of "goodness" across myriad models and uses assumptions consistent with known facts. My colleagues and I use such methods to address intractable policy issues fraught with arguments over which model is "right", what assumptions are valid and what is the nature of the good? This method makes the decision to be informed part of the analysis itself and the results are more readily accepted by policymakers. That was from a senior economist at RAND. So it looks as if at least some members of the current military-industrial complex are using simulations in a sensible and valid way (certainly with more sense and validity than a lot of the academic papers I see). So if 'valid' simulations are being used to give the 'wrong' answers, what does that tell us about simulation? Is there ever any hope of objectivity (I'll give away the answer to that: no) or do all social simulations - political or economic - inevitably reflect the prejudices of their author or funder? Robert -------------- next part -------------- An HTML attachment was scrubbed... URL: /pipermail/friam_redfish.com/attachments/20060808/8319a729/attachment.html |
Lately I have been doing simulations of wildfires. The program that I
have been using (Farsite) is based on first principles of fire physics. Assuming that the inputs are correct (elevation, slope, aspect, fuel, canopy, wind, temperature, humidity and a few others) I suspect the estimate of the fire area as a function of time, and even the footprint represents a fairly accurate prediction. Maybe there is a definition of "complex system" that is related to the question of what kinds of predictions simulations of them can yield? Frank --- Frank C. Wimberly 140 Calle Ojo Feliz??????????????(505) 995-8715 or (505) 670-9918 (cell) Santa Fe, NM 87505???????????wimberly3 at earthlink.net -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Robert Holmes Sent: Tuesday, August 08, 2006 1:17 PM To: FRIAM Subject: [FRIAM] Simulation and policy-making Here's a quote from a letter in this week's Economist about how to use big economic models: The root of many problems lies not in the [economic] models themselves but in the way in which they are used. Too often we ask "What will happen?", trapping us into the mug's game of prediction, when the real question should be: "Given that we cannot predict, what is our best move today?"...Instead of determining the "best" model that solves optimal strategies we should instead seek the most "robust" model that achieves a given level of "goodness" across myriad models and uses assumptions consistent with known facts. My colleagues and I use such methods to address intractable policy issues fraught with arguments over which model is "right", what assumptions are valid and what is the nature of the good? This method makes the decision to be informed part of the analysis itself and the results are more readily accepted by policymakers. That was from a senior economist at RAND. So it looks as if at least some members of the current military-industrial complex are using simulations in a sensible and valid way (certainly with more sense and validity than a lot of the academic papers I see). So if 'valid' simulations are being used to give the 'wrong' answers, what does that tell us about simulation? Is there ever any hope of objectivity (I'll give away the answer to that: no) or do all social simulations - political or economic - inevitably reflect the prejudices of their author or funder? Robert |
In reply to this post by Robert Holmes
Quoting Robert Holmes <robert at holmesacosta.com>:
> So if 'valid' simulations are being used to give the 'wrong' answers, what > does that tell us about simulation? Is there ever any hope of objectivity > (I'll give away the answer to that: no) or do all social simulations - > political or economic - inevitably reflect the prejudices of their author or > funder? Validated simulations, by definition, reproduce something that the authors (or funders) deem relevant as a performance metric. But that's not a problem with models or simulations, assuming the metrics are documented. If the authors or funders are prone to choosing easy, low dimensional things to fit, they just need to be more ambitious. |
Oh I thank RAND are probably plenty ambitious in what they simulate for the
US govt. Just check out their research areas: http://www.rand.org/research_areas/ Robert On 8/8/06, mgd at santafe.edu <mgd at santafe.edu> wrote: > > Quoting Robert Holmes <robert at holmesacosta.com>: > > > So if 'valid' simulations are being used to give the 'wrong' answers, > what > > does that tell us about simulation? Is there ever any hope of > objectivity > > (I'll give away the answer to that: no) or do all social simulations - > > political or economic - inevitably reflect the prejudices of their > author or > > funder? > > Validated simulations, by definition, reproduce something that the authors > (or > funders) deem relevant as a performance metric. But that's not a problem > with > models or simulations, assuming the metrics are documented. If the > authors or > funders are prone to choosing easy, low dimensional things to fit, they > just > need to be more ambitious. > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org > An HTML attachment was scrubbed... URL: /pipermail/friam_redfish.com/attachments/20060808/b577b087/attachment.html |
Re: simulation and policy-making, a project that my group is working on at
the request of the current Washington administration is helping to do just that. At the request of a consortium of representatives from the White House, Dept of Treasury, DHS, Dept. of State, and a few other cabinet-level political types, we have run numerous simulation experimental designs to establish the bounds of the effectiveness of various intervention strategies for containing an H5N1 pandemic, should it occur in the US. We are using three simulation codes: EpiSims, Epicast, and one from the Imperial College in the UK. The name of the project is "Models of Infectious Disease Agent Study" (MIDAS), and it is funded by NIH. See http://www.hsph.harvard.edu/press/releases/press02202006.html and http://usinfo.state.gov/gi/Archive/2005/Aug/08-339612.html or do a google search on "MIDAS bird flu policy" for more info. --Doug On 8/8/06, Robert Holmes <robert at holmesacosta.com> wrote: > > Oh I thank RAND are probably plenty ambitious in what they simulate for > the US govt. Just check out their research areas: > http://www.rand.org/research_areas/ > > Robert > > > On 8/8/06, mgd at santafe.edu <mgd at santafe.edu> wrote: > > > > Quoting Robert Holmes <robert at holmesacosta.com>: > > > > > So if 'valid' simulations are being used to give the 'wrong' answers, > > what > > > does that tell us about simulation? Is there ever any hope of > > objectivity > > > (I'll give away the answer to that: no) or do all social simulations - > > > political or economic - inevitably reflect the prejudices of their > > author or > > > funder? > > > > Validated simulations, by definition, reproduce something that the > > authors (or > > funders) deem relevant as a performance metric. But that's not a > > problem with > > models or simulations, assuming the metrics are documented. If the > > authors or > > funders are prone to choosing easy, low dimensional things to fit, they > > just > > need to be more ambitious. > > > > ============================================================ > > FRIAM Applied Complexity Group listserv > > Meets Fridays 9a-11:30 at cafe at St. John's College > > lectures, archives, unsubscribe, maps at http://www.friam.org > > > > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org > > -- Doug Roberts, RTI International droberts at rti.org doug at parrot-farm.net 505-455-7333 - Office 505-670-8195 - Cell -------------- next part -------------- An HTML attachment was scrubbed... URL: /pipermail/friam_redfish.com/attachments/20060808/c79b7e63/attachment-0001.html |
Computational social science doesn't lend itself to V&V the way that physics-based mod-sim does, so creativity in V&V is required.
But when it comes to policy making, then, the question is, "What does it mean to use modeling and simulation tools appropriately in producing knowledge that will feed into policy decisions?" The answer to this question is going to vary depending on the time scale for the decision (longer term planning vs. shorter term, highly tactical decision making).There are probably lots of other issues as well that I'm not thinking of because I really need another cup of coffee after a long night of lightning, thunder and terrified dogs. That said, I think what Doug described below - experimental design, different modeling and simulation packages, expertise and care - is a great start. Those of you attending FRIAM on the 18th of August... I'll be there with my Sandia buddy, Tim Trucano, and we're thinking about models, V&V, uncertainty, and policy-making pretty carefully these days because of some work we're pursuing with the Department of Defense. We'd love to engage in a good solid discussion about this topic with the FRIAM brain trust, so bring your ideas along. Laura -----Original Message----- From: [hidden email] on behalf of Douglas Roberts Sent: Tue 8/8/2006 7:40 PM To: The Friday Morning Applied Complexity Coffee Group Subject: Re: [FRIAM] Simulation and policy-making Re: simulation and policy-making, a project that my group is working on at the request of the current Washington administration is helping to do just that. At the request of a consortium of representatives from the White House, Dept of Treasury, DHS, Dept. of State, and a few other cabinet-level political types, we have run numerous simulation experimental designs to establish the bounds of the effectiveness of various intervention strategies for containing an H5N1 pandemic, should it occur in the US. We are using three simulation codes: EpiSims, Epicast, and one from the Imperial College in the UK. The name of the project is "Models of Infectious Disease Agent Study" (MIDAS), and it is funded by NIH. See http://www.hsph.harvard.edu/press/releases/press02202006.html and http://usinfo.state.gov/gi/Archive/2005/Aug/08-339612.html or do a google search on "MIDAS bird flu policy" for more info. --Doug On 8/8/06, Robert Holmes <robert at holmesacosta.com> wrote: > > Oh I thank RAND are probably plenty ambitious in what they simulate for > the US govt. Just check out their research areas: > http://www.rand.org/research_areas/ > > Robert > > > On 8/8/06, mgd at santafe.edu <mgd at santafe.edu> wrote: > > > > Quoting Robert Holmes <robert at holmesacosta.com>: > > > > > So if 'valid' simulations are being used to give the 'wrong' answers, > > what > > > does that tell us about simulation? Is there ever any hope of > > objectivity > > > (I'll give away the answer to that: no) or do all social simulations - > > > political or economic - inevitably reflect the prejudices of their > > author or > > > funder? > > > > Validated simulations, by definition, reproduce something that the > > authors (or > > funders) deem relevant as a performance metric. But that's not a > > problem with > > models or simulations, assuming the metrics are documented. If the > > authors or > > funders are prone to choosing easy, low dimensional things to fit, they > > just > > need to be more ambitious. > > > > ============================================================ > > FRIAM Applied Complexity Group listserv > > Meets Fridays 9a-11:30 at cafe at St. John's College > > lectures, archives, unsubscribe, maps at http://www.friam.org > > > > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org > > -- Doug Roberts, RTI International droberts at rti.org doug at parrot-farm.net 505-455-7333 - Office 505-670-8195 - Cell -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/ms-tnef Size: 5037 bytes Desc: not available Url : /pipermail/friam_redfish.com/attachments/20060809/055d5c70/attachment-0001.bin |
On 8/9/06, McNamara, Laura A <lamcnam at sandia.gov> wrote:
> > Computational social science doesn't lend itself to V&V the way that > physics-based mod-sim does, so creativity in V&V is required... I agree, and I think the approach that RAND take is as good as any. My concern though is that any social science model is inevitably subjective at a deep, deep level. You want a simulation that shows it's a good idea to invade Iraq? No problem, I'll interview a bunch of experts, code up realistic micro-rules and give you a simulation that shows yes, that's a sensible policy. You want a simulation that shows it's not a good idea to invade Iraq? No problem, I'll just interview a different set of experts, get some different micro-rules in there and voila, I've shown invasion is a Bad Thing. Like I said, I'm getting more and more convinced that social science ABMs just project the prejudices of their authors/funders. Or does anyone have an example of an objective 'uncorrupted' social science ABM? Robert -------------- next part -------------- An HTML attachment was scrubbed... URL: /pipermail/friam_redfish.com/attachments/20060809/54a0e931/attachment.html |
Quoting Robert Holmes <robert at holmesacosta.com>:
> You want a simulation that shows it's a good idea to > invade Iraq? No problem, I'll interview a bunch of experts, code up > realistic micro-rules and give you a simulation that shows yes, that's a > sensible policy. You want a simulation that shows it's not a good idea to > invade Iraq? No problem, I'll just interview a different set of experts, get > some different micro-rules in there and voila, I've shown invasion is a Bad > Thing. Two ways to deal with that problem. 1) Data Experts can suggest micro-rules, but then provide examples when those micro- rules were used and other cases where different micro-rules were used, and historical accounts of what happened in each case. In other words do retrodiction on a past similar system that had a known result. If there are no such systems, and no way to change plans or modify a plan (based on early data), then indeed the forecasts are suspect and vulnerable to manipulation. 2) Peer review Not all experts will agree on micro-rules. Get a range of micro-rules from different experts and compute the range of possibility for all of them. Marcus |
In reply to this post by Douglas Roberts-2
Cool! Now there's a meaningful global modeling task, an event map with
a basically simple dynamic model, that involves mixing a core of advanced eco-system dynamics with a limited cross section of interdisciplinary autonomous agents. It's a very demanding but conceptually realistic task that can be kept to what's working. Not to be discounted is the nearly ideal information output intended. The product of that effort would be used to feed a sophisticated global public health system with better images and contingency plans for what they might run into, widely disseminating the learning and generating volumes of quality guiding feedback. That kind of purpose is set up for greatly advancing our ability to live on earth. Those who want to use the tools of systems inquiry for secretly generating new kinds of weapons for central authorities to interfere with what interests them, won't actually learn much and will cause great harm. Phil Henshaw ????.?? ? `?.???? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 680 Ft. Washington Ave NY NY 10040 tel: 212-795-4844 e-mail: pfh at synapse9.com explorations: www.synapse9.com <http://www.synapse9.com/> -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Douglas Roberts Sent: Tuesday, August 08, 2006 9:40 PM To: The Friday Morning Applied Complexity Coffee Group Subject: Re: [FRIAM] Simulation and policy-making Re: simulation and policy-making, a project that my group is working on at the request of the current Washington administration is helping to do just that. At the request of a consortium of representatives from the White House, Dept of Treasury, DHS, Dept. of State, and a few other cabinet-level political types, we have run numerous simulation experimental designs to establish the bounds of the effectiveness of various intervention strategies for containing an H5N1 pandemic, should it occur in the US. We are using three simulation codes: EpiSims, Epicast, and one from the Imperial College in the UK. The name of the project is "Models of Infectious Disease Agent Study" (MIDAS), and it is funded by NIH. See http://www.hsph.harvard.edu/press/releases/press02202006.html and http://usinfo.state.gov/gi/Archive/2005/Aug/08-339612.html or do a google search on "MIDAS bird flu policy" for more info. --Doug On 8/8/06, Robert Holmes <robert at holmesacosta.com> wrote: Oh I thank RAND are probably plenty ambitious in what they simulate for the US govt. Just check out their research areas: http://www.rand.org/research_areas/ Robert On 8/8/06, mgd at santafe.edu < mgd at santafe.edu <mailto:mgd at santafe.edu> > wrote: Quoting Robert Holmes <robert at holmesacosta.com>: > So if 'valid' simulations are being used to give the 'wrong' answers, what > does that tell us about simulation? Is there ever any hope of objectivity > (I'll give away the answer to that: no) or do all social simulations - > political or economic - inevitably reflect the prejudices of their author or > funder? Validated simulations, by definition, reproduce something that the authors (or funders) deem relevant as a performance metric. But that's not a problem with models or simulations, assuming the metrics are documented. If the authors or funders are prone to choosing easy, low dimensional things to fit, they just need to be more ambitious. ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org -- Doug Roberts, RTI International droberts at rti.org doug at parrot-farm.net 505-455-7333 - Office 505-670-8195 - Cell -------------- next part -------------- An HTML attachment was scrubbed... URL: /pipermail/friam_redfish.com/attachments/20060809/9f4c649d/attachment-0001.html |
Phil,
Not quite, unfortunately. EpiSims, and other similar ABMs can all too easily be used to identify weaknesses and potential exploits of social infrastructures. We did studies for the US DHS that demonstrated exactly this a couple of years ago when I still worked at LANL. One example was when we simulated the release of a weaponized aerosol pneumonic plague disease agent in a certain busy subway station during a simulated rush hour in a simulated Chicago with a simulated population of 6.2 million people... --Doug On 8/9/06, Phil Henshaw <sy at synapse9.com> wrote: > > > > Those who want to use the tools of systems inquiry for secretly generating > new kinds of weapons for central authorities to interfere with what > interests them, won't actually learn much and will cause great harm. > > > > Phil Henshaw ????.?? ? `?.???? > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > 680 Ft. Washington Ave > NY NY 10040 > tel: 212-795-4844 > e-mail: pfh at synapse9.com > explorations: www.synapse9.com > > -----Original Message----- > *From:* friam-bounces at redfish.com [mailto:friam-bounces at redfish.com] *On > Behalf Of *Douglas Roberts > *Sent:* Tuesday, August 08, 2006 9:40 PM > *To:* The Friday Morning Applied Complexity Coffee Group > *Subject:* Re: [FRIAM] Simulation and policy-making > > Re: simulation and policy-making, a project that my group is working on at > the request of the current Washington administration is helping to do just > that. At the request of a consortium of representatives from the White > House, Dept of Treasury, DHS, Dept. of State, and a few other cabinet-level > political types, we have run numerous simulation experimental designs to > establish the bounds of the effectiveness of various intervention strategies > for containing an H5N1 pandemic, should it occur in the US. We are using > three simulation codes: EpiSims, Epicast, and one from the Imperial College > in the UK. The name of the project is "Models of Infectious Disease Agent > Study" (MIDAS), and it is funded by NIH. See > > http://www.hsph.harvard.edu/press/releases/press02202006.html and > http://usinfo.state.gov/gi/Archive/2005/Aug/08-339612.html > > or do a google search on "MIDAS bird flu policy" for more info. > > --Doug > > On 8/8/06, Robert Holmes <robert at holmesacosta.com> wrote: > > > > Oh I thank RAND are probably plenty ambitious in what they simulate for > > the US govt. Just check out their research areas: > > http://www.rand.org/research_areas/ > > > > Robert > > > > > > On 8/8/06, mgd at santafe.edu < mgd at santafe.edu> wrote: > > > > > > Quoting Robert Holmes <robert at holmesacosta.com>: > > > > > > > So if 'valid' simulations are being used to give the 'wrong' > > > answers, what > > > > does that tell us about simulation? Is there ever any hope of > > > objectivity > > > > (I'll give away the answer to that: no) or do all social simulations > > > - > > > > political or economic - inevitably reflect the prejudices of their > > > author or > > > > funder? > > > > > > Validated simulations, by definition, reproduce something that the > > > authors (or > > > funders) deem relevant as a performance metric. But that's not a > > > problem with > > > models or simulations, assuming the metrics are documented. If the > > > authors or > > > funders are prone to choosing easy, low dimensional things to fit, > > > they just > > > need to be more ambitious. > > > > > > ============================================================ > > > FRIAM Applied Complexity Group listserv > > > Meets Fridays 9a-11:30 at cafe at St. John's College > > > lectures, archives, unsubscribe, maps at http://www.friam.org > > > > > > > > > ============================================================ > > FRIAM Applied Complexity Group listserv > > Meets Fridays 9a-11:30 at cafe at St. John's College > > lectures, archives, unsubscribe, maps at http://www.friam.org > > > > > > > -- > Doug Roberts, RTI International > droberts at rti.org > doug at parrot-farm.net > 505-455-7333 - Office > 505-670-8195 - Cell > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org > > -- Doug Roberts, RTI International droberts at rti.org doug at parrot-farm.net 505-455-7333 - Office 505-670-8195 - Cell -------------- next part -------------- An HTML attachment was scrubbed... URL: /pipermail/friam_redfish.com/attachments/20060810/c6ef972a/attachment.html |
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