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One of my projects

Paul Paryski
For someone like me who rarely works with such complex models this is a  very
interesting discussion.  Out of my ignorance a couple of questions  have
popped into my aging synapses:
-does the model include mutation and other adaptations by diseases?
-are you going to study past massive epidemics to see what patterns are  
applicable (bio mimicry and incidence of natural immunity, cultural  practices)
-who will make the political choice to use the info/models when the time  
comes?
 
Paul Paryski
 
 



************************************** See what's free at http://www.aol.com.
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One of my projects

Douglas Roberts-2
A few of you have asked questions about the the EpiSims-Grid project, so
I'll try to answer them here, in roughly inverse order that they were
received:



From: Paul Paryski:

 For someone like me who rarely works with such complex models this is a
> very interesting discussion.  Out of my ignorance a couple of questions have
> popped into my aging synapses:
> -does the model include mutation and other adaptations by diseases?
>

No, we have only simulated one pathogen at a time, to date, and it does not
mutate.

-are you going to study past massive epidemics to see what patterns are
> applicable (bio mimicry and incidence of natural immunity, cultural
> practices)
>

Yes, we have done this fairly extensively.  Lots of data exists from the
1918 pandemic flu outbreak, for example.

-who will make the political choice to use the info/models when the time
> comes?
>

Good question.  See my response to Laura Mac's questions bleow.

>From Laura MacNamara:

Being someone who studies people who use models, I'm curious about how you
guys are relating to your user community.  Who are the intended analysts
(the ones that you hope know what you're doing)?   At what point do you guys
start engaging them?  Do they treat your simulation as black box?


Our last study was commissioned by a high-level consortium of
Department-level representatives -- Dept. of State, Dept. of Treasury, Dept.
of Homeland Security, Dept. of HHS, and the office of the White House.  The
purpose of the study was to help them identify relative measures of
effectiveness regarding what intervention strategies would provide the most
benefit in the event of  a pandemic flu outbreak.  Examples of intervention
strategies that were modeled included

   1. Self-isolation (staying home when symptomatic)
   2. Social distancing (telecommuting, scheduled trips to the store with
   minimal contact to other shoppers, in general minimizing physical proximity
   to other people) during an outbreak
   3. Closing down schools and non-critical workplaces
   4. Treating critical infrastructure workers with anti-viral treatments
   (remember -- it was a pandemic being simulated, there were no vaccines)
   5. etc.

The intent was to help government officials develop a response plan in the
event of an outbreak.  I was quite impressed with the expertise with which
the leader of the study, the White House representative, directed the
study.  He was one of the most knowledgeable and intelligent of any of the
customers that I have aver worked with.  The simulations used in the study
were most definitely not treated as black boxes.  Rather, the strengths and
weaknesses of each of the three models were thoroughly explored.

The consortium of users approached the leader of the MIDAS project and
requested our participation on the project last summer, at which point we
immediately engaged with them to develop an experimental design.

>From Robert Holmes:

Fair enough: big simulation answers some questions, small simulation answers
others. So what are the specific questions that a big epidemiological
simulation can answer? It can't be anything too predictive ("ohmigod, New
York has just fallen to small pox. Which city is next?") because that
depends (I'd guess) on something that is unsimulatable ("errr.... dunno.
Kinda depends which flight the guy with small pox got onto"). What are the
questions that can only be answered with a big model?

EpiSims was by far the most detailed of the three models used.  It is an
individual-based ABM in which the second-to-second movements of every
individual in the 8.6-million population city were modeled for 60
consecutive 24-hour days.  Further, each individual was fairly completely
characterized demographically -- race, inccome, marital status, number of
children, etc.  Also, family household structures are created by EpiSims, in
which the same adults and children come back to the same household every
day.

This level of detail allowed us to run experiments on specific demographic
subsets of the population that were not possible with the other models.  For
example, we ran a series of experiments for which social distancing was less
effective among lower income people, because they could not afford to stay
home -- they had to work.  These runs were compared to runs where all
working members of the population had the same compliance when social
distancing measures were imposed.

Another example of experiments that were conducted with EpiSims that could
not be achieved with the other models: we ran several experiments in which
the imuno-response of lower economic segments of the population was less
effective in resisting the pandemic virus then for those more affluent
members of the population.  The reasoning being that poorer people have less
access to health care.

Remember, the intent of these studies was to establish a relative
effectiveness ranking determination of various intervention strategies for
future use establishing a response strategy in the event of a pandemic
outbreak.  The intent was *not* to model "ohmigod, New York has just fallen
to small pox. Which city is next?" types of human behavior in response to an
outbreak.

I hope this addresses some of your questions.  Thanks for your interest!

--Doug



--
Doug Roberts, RTI International
droberts at rti.org
doug at parrot-farm.net
505-455-7333 - Office
505-670-8195 - Cell
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One of my projects

Phil Henshaw-2
Doug,
Did you not answer my question just because it seemed obvious or
something?    The other questions and your other answers all seemed very
thoughtful, but didn't address mine.    I'm thinking the use of the tool
would include helping people in the learning process of finding what is
actually working during the experience of an epidemic.   Every pathogen
and every public health initiative will have different growth dynamic
characteristics, and sometimes very small differences will have large
effects, especially because of relative lag times of divergence and
response.    I was commenting, I guess, on the difference between a
universal general model of epidemic spread and response and the
particular event process of an individual epidemic and the creative
adaptation an effective response requires.
 
 

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: Friday, March 30, 2007 5:45 PM
To: The Friday Morning Applied Complexity Coffee Group
Subject: Re: [FRIAM] One of my projects


A few of you have asked questions about the the EpiSims-Grid project, so
I'll try to answer them here, in roughly inverse order that they were
received:




From: Paul Paryski:




For someone like me who rarely works with such complex models this is a
very interesting discussion.  Out of my ignorance a couple of questions
have popped into my aging synapses:
-does the model include mutation and other adaptations by diseases?


No, we have only simulated one pathogen at a time, to date, and it does
not mutate.




-are you going to study past massive epidemics to see what patterns are
applicable (bio mimicry and incidence of natural immunity, cultural
practices)


Yes, we have done this fairly extensively.  Lots of data exists from the
1918 pandemic flu outbreak, for example.




-who will make the political choice to use the info/models when the time
comes?


Good question.  See my response to Laura Mac's questions bleow.


>From Laura MacNamara:

Being someone who studies people who use models, I'm curious about how
you guys are relating to your user community.  Who are the intended
analysts (the ones that you hope know what you're doing)?   At what
point do you guys start engaging them?  Do they treat your simulation as
black box?


Our last study was commissioned by a high-level consortium of
Department-level representatives -- Dept. of State, Dept. of Treasury,
Dept. of Homeland Security, Dept. of HHS, and the office of the White
House.  The purpose of the study was to help them identify relative
measures of effectiveness regarding what intervention strategies would
provide the most benefit in the event of  a pandemic flu outbreak.
Examples of intervention strategies that were modeled included


1. Self-isolation (staying home when symptomatic)

2. Social distancing (telecommuting, scheduled trips to the store
with minimal contact to other shoppers, in general minimizing physical
proximity to other people) during an outbreak


3. Closing down schools and non-critical workplaces


4. Treating critical infrastructure workers with anti-viral
treatments (remember -- it was a pandemic being simulated, there were no
vaccines)

5. etc.

The intent was to help government officials develop a response plan in
the event of an outbreak.  I was quite impressed with the expertise with
which the leader of the study, the White House representative, directed
the study.  He was one of the most knowledgeable and intelligent of any
of the customers that I have aver worked with.  The simulations used in
the study were most definitely not treated as black boxes.  Rather, the
strengths and weaknesses of each of the three models were thoroughly
explored.  

The consortium of users approached the leader of the MIDAS project and
requested our participation on the project last summer, at which point
we immediately engaged with them to develop an experimental design.

>From Robert Holmes:

Fair enough: big simulation answers some questions, small simulation
answers others. So what are the specific questions that a big
epidemiological simulation can answer? It can't be anything too
predictive ("ohmigod, New York has just fallen to small pox. Which city
is next?") because that depends (I'd guess) on something that is
unsimulatable ("errr.... dunno. Kinda depends which flight the guy with
small pox got onto"). What are the questions that can only be answered
with a big model?

EpiSims was by far the most detailed of the three models used.  It is an
individual-based ABM in which the second-to-second movements of every
individual in the 8.6-million population city were modeled for 60
consecutive 24-hour days.  Further, each individual was fairly
completely characterized demographically -- race, inccome, marital
status, number of children, etc.  Also, family household structures are
created by EpiSims, in which the same adults and children come back to
the same household every day.  

This level of detail allowed us to run experiments on specific
demographic subsets of the population that were not possible with the
other models.  For example, we ran a series of experiments for which
social distancing was less effective among lower income people, because
they could not afford to stay home -- they had to work.  These runs were
compared to runs where all working members of the population had the
same compliance when social distancing measures were imposed.

Another example of experiments that were conducted with EpiSims that
could not be achieved with the other models: we ran several experiments
in which the imuno-response of lower economic segments of the population
was less effective in resisting the pandemic virus then for those more
affluent members of the population.  The reasoning being that poorer
people have less access to health care.

Remember, the intent of these studies was to establish a relative
effectiveness ranking determination of various intervention strategies
for future use establishing a response strategy in the event of a
pandemic outbreak.  The intent was *not* to model "ohmigod, New York has
just fallen to small pox. Which city is next?" types of human behavior
in response to an outbreak.

I hope this addresses some of your questions.  Thanks for your interest!

--Doug



--
Doug Roberts, RTI International
droberts at rti.org
doug at parrot-farm.net
505-455-7333 - Office
505-670-8195 - Cell

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One of my projects

Douglas Roberts-2
Phil,

I did read your question, repeated below:

Cool, do you include any comparative natural system component?  Perhaps
working with better ways to identify system structures in natural systems
and early signs of when they are inventing new ones would be helpful in
developing tests for models that approximate the complexity of nature.


However, I found it to be sufficiently ambiguous that I had absolutely no
idea what was being asked, and thus found myself at a complete loss for a
response.

--
Doug Roberts, RTI International
droberts at rti.org
doug at parrot-farm.net
505-455-7333 - Office
505-670-8195 - Cell


On 3/31/07, Phil Henshaw <sy at synapse9.com> wrote:

>
>  Doug,
> Did you not answer my question just because it seemed obvious or
> something?    The other questions and your other answers all seemed very
> thoughtful, but didn't address mine.    I'm thinking the use of the tool
> would include helping people in the learning process of finding what is
> actually working during the experience of an epidemic.   Every pathogen and
> every public health initiative will have different growth dynamic
> characteristics, and sometimes very small differences will have large
> effects, especially because of relative lag times of divergence and
> response.    I was commenting, I guess, on the difference between a
> universal general model of epidemic spread and response and the particular
> event process of an individual epidemic and the creative adaptation an
> effective response requires.
>
>
>
> 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:* Friday, March 30, 2007 5:45 PM
> *To:* The Friday Morning Applied Complexity Coffee Group
> *Subject:* Re: [FRIAM] One of my projects
>
> A few of you have asked questions about the the EpiSims-Grid project, so
> I'll try to answer them here, in roughly inverse order that they were
> received:
>
>
>
> From: Paul Paryski:
>
>  For someone like me who rarely works with such complex models this is a
> > very interesting discussion.  Out of my ignorance a couple of questions have
> > popped into my aging synapses:
> > -does the model include mutation and other adaptations by diseases?
> >
>
> No, we have only simulated one pathogen at a time, to date, and it does
> not mutate.
>
>  -are you going to study past massive epidemics to see what patterns are
> > applicable (bio mimicry and incidence of natural immunity, cultural
> > practices)
> >
>
> Yes, we have done this fairly extensively.  Lots of data exists from the
> 1918 pandemic flu outbreak, for example.
>
>  -who will make the political choice to use the info/models when the time
> > comes?
> >
>
> Good question.  See my response to Laura Mac's questions bleow.
>
> From Laura MacNamara:
>
> Being someone who studies people who use models, I'm curious about how you
> guys are relating to your user community.  Who are the intended analysts
> (the ones that you hope know what you're doing)?   At what point do you guys
> start engaging them?  Do they treat your simulation as black box?
>
>
> Our last study was commissioned by a high-level consortium of
> Department-level representatives -- Dept. of State, Dept. of Treasury, Dept.
> of Homeland Security, Dept. of HHS, and the office of the White House.  The
> purpose of the study was to help them identify relative measures of
> effectiveness regarding what intervention strategies would provide the most
> benefit in the event of  a pandemic flu outbreak.  Examples of intervention
> strategies that were modeled included
>
>    1. Self-isolation (staying home when symptomatic)
>    2. Social distancing (telecommuting, scheduled trips to the store
>    with minimal contact to other shoppers, in general minimizing physical
>    proximity to other people) during an outbreak
>    3. Closing down schools and non-critical workplaces
>    4. Treating critical infrastructure workers with anti-viral
>    treatments (remember -- it was a pandemic being simulated, there were no
>    vaccines)
>    5. etc.
>
> The intent was to help government officials develop a response plan in the
> event of an outbreak.  I was quite impressed with the expertise with which
> the leader of the study, the White House representative, directed the
> study.  He was one of the most knowledgeable and intelligent of any of the
> customers that I have aver worked with.  The simulations used in the study
> were most definitely not treated as black boxes.  Rather, the strengths and
> weaknesses of each of the three models were thoroughly explored.
>
> The consortium of users approached the leader of the MIDAS project and
> requested our participation on the project last summer, at which point we
> immediately engaged with them to develop an experimental design.
>
> From Robert Holmes:
>
> Fair enough: big simulation answers some questions, small simulation
> answers others. So what are the specific questions that a big
> epidemiological simulation can answer? It can't be anything too predictive
> ("ohmigod, New York has just fallen to small pox. Which city is next?")
> because that depends (I'd guess) on something that is unsimulatable
> ("errr.... dunno. Kinda depends which flight the guy with small pox got
> onto"). What are the questions that can only be answered with a big model?
>
> EpiSims was by far the most detailed of the three models used.  It is an
> individual-based ABM in which the second-to-second movements of every
> individual in the 8.6-million population city were modeled for 60
> consecutive 24-hour days.  Further, each individual was fairly completely
> characterized demographically -- race, inccome, marital status, number of
> children, etc.  Also, family household structures are created by EpiSims, in
> which the same adults and children come back to the same household every
> day.
>
> This level of detail allowed us to run experiments on specific demographic
> subsets of the population that were not possible with the other models.  For
> example, we ran a series of experiments for which social distancing was less
> effective among lower income people, because they could not afford to stay
> home -- they had to work.  These runs were compared to runs where all
> working members of the population had the same compliance when social
> distancing measures were imposed.
>
> Another example of experiments that were conducted with EpiSims that could
> not be achieved with the other models: we ran several experiments in which
> the imuno-response of lower economic segments of the population was less
> effective in resisting the pandemic virus then for those more affluent
> members of the population.  The reasoning being that poorer people have less
> access to health care.
>
> Remember, the intent of these studies was to establish a relative
> effectiveness ranking determination of various intervention strategies for
> future use establishing a response strategy in the event of a pandemic
> outbreak.  The intent was *not* to model "ohmigod, New York has just
> fallen to small pox. Which city is next?" types of human behavior in
> response to an outbreak.
>
> I hope this addresses some of your questions.  Thanks for your interest!
>
> --Doug
>
>
>
> --
> 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
>
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One of my projects

Alfredo Covaleda
In reply to this post by Douglas Roberts-2
Congratulations  Douglas

1) Do  you include different levels of virulence in your simulation?


2) Do you consider  vectors  in the spread of diseases ?


3) Will you extend your work to study other pathosystems (I mean in
plants or even arthropoda)?


Regards

Alfredo

---------------------------
Alfredo Covaleda V?lez
Ingeniero Agr?nomo - Programador
Tel?fono: 3112137829
Bogot? D.C. -  Colombia
---------------------------




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One of my projects

Douglas Roberts-2
Hi, Alfredo.

In the past, we have modeled a variety of influenza strains, some more
virulent than others.  We have conducted simulations of infections of
influenza A & B, avian influenza, as well as smallpox, anthrax, pneumonic
plague and bubonic plague in a series of previous studies.

The vectors of disease spread emerge from the person-person interactions as
EpiSims simulates the second-to-second movements and activities of all
people in the region of interest.  These interactions occur in the work
place, at home, while shopping, during recreational activities, while
commuting, etc.  The vectors of disease spread are of course studied for
insight into potential intervention strategies.

EpiSims can be used to model the spread of any infectious agent whose human
health characteristics can be captured by a Markov chain state
representation.

Regards,

--Doug

--
Doug Roberts, RTI International
droberts at rti.org
doug at parrot-farm.net
505-455-7333 - Office

On 4/2/07, Alfredo <agbioinfo at gmx.net> wrote:

>
>  Congratulations  Douglas
>
> 1) Do  you include different levels of virulence in your simulation?
>
>
> 2) Do you consider  vectors  in the spread of diseases ?
>
>
> 3) Will you extend your work to study other pathosystems (I mean in plants
> or even arthropoda)?
>
>
> Regards
>
> Alfredo
>
> ---------------------------
> Alfredo Covaleda V?lez
> Ingeniero Agr?nomo - Programador
> Tel?fono: 3112137829
> Bogot? D.C. -  Colombia
> ---------------------------
>
>
>
>
>
> ============================================================
> 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
>




505-670-8195 - Cell
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One of my projects

Parks, Raymond
In reply to this post by Douglas Roberts-2
Doug,

   I wonder how EpiSIMS results would compare to introducing a viral
actor into "The SIMS" ore "Second Life"?  Would there be some difference
in emergent behavior of real people running their avatars from agents,
however realistically programmed, running their code?

--
Ray Parks                   rcparks at sandia.gov
IDART Project Lead          Voice:505-844-4024
IORTA Department            Mobile:505-238-9359
http://www.sandia.gov/scada Fax:505-844-9641
http://www.sandia.gov/idart Pager:800-690-5288



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One of my projects

Douglas Roberts-2
Hi, Ray.

One will seldom, if ever get identical behavior from two different codes,
even if the inputs are identical.

The emergent behavior that could be observed from EpiSims, The SIMS, and
Second Life, assuming the latter two could emulate responses to the
introduction of a viral pathogen, will vary based directly on the
differences of granularity with with the agents are implemented in the
simulations.

--Doug

--
Doug Roberts, RTI International
droberts at rti.org
doug at parrot-farm.net
505-455-7333 - Office
505-670-8195 - Cell

On 4/4/07, Raymond Parks <rcparks at sandia.gov> wrote:

>
> Doug,
>
>    I wonder how EpiSIMS results would compare to introducing a viral
> actor into "The SIMS" ore "Second Life"?  Would there be some difference
> in emergent behavior of real people running their avatars from agents,
> however realistically programmed, running their code?
>
> --
> Ray Parks                   rcparks at sandia.gov
> IDART Project Lead          Voice:505-844-4024
> IORTA Department            Mobile:505-238-9359
> http://www.sandia.gov/scada Fax:505-844-9641
> http://www.sandia.gov/idart Pager:800-690-5288
>
>
> ============================================================
> 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
>
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One of my projects

Parks, Raymond
Doug,

You wrote:
> One will seldom, if ever get identical behavior from two different
> codes, even if the inputs are identical.
 >
> The emergent behavior that could be observed from EpiSims, The SIMS, and
> Second Life, assuming the latter two could emulate responses to the
> introduction of a viral pathogen, will vary based directly on the
> differences of granularity with with the agents are implemented in the
> simulations.

   Given that the "agents" in The Sims and Second Life are avatars for
real people, one could argue that their code is more realistic than
agent code.  Their granularity is basically as small as one can get -
some MMORPGs allow for more than one character per player but they are
still one character per character.  One problem I can see would be that
MMORPGs in general suffer from the lack of full participation - EpiSims
models every second of human behaviour for a large population, but
MMORPG players are not playing their avatars all of the time.

   I wonder if some combination would play to the strengths of both
systems.  Could one use something like EpiSims running at wall-clock
speed as the background for avatars played by real people?  Then the
simulated people agent code could self-modify on the fly to model the
behaviour of the real people.  I'm starting to sound like the
explanation of the fake Rock Ridge in "Blazing Saddles".

--
Ray Parks                   rcparks at sandia.gov
IDART Project Lead          Voice:505-844-4024
IORTA Department            Mobile:505-238-9359
http://www.sandia.gov/scada Fax:505-844-9641
http://www.sandia.gov/idart Pager:800-690-5288



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One of my projects

Douglas Roberts-2
Ray,

Please explain how the "avatars" will know when they have been infected by a
virus, and how they will respond to that.

In fact, please explain how the "avatars" know when go to work, when and
where to go shopping, know when an epidemic has been announced; how they
will respond to a decreed intervention strategy of keeping the kids home
from school?  What will be the "avatar" level of compliance to the declared
regime of intervention strategy?  How many will accept anti-viral
treatment?  How many will wear masks to work?  How many will comply to
government requests to self-isolate when they become symptomatic?  How will
an "avatar" determine when it has become symptomatic?

With what level of resolution will these "avatars" behave in the simulation?

--Doug

--
Doug Roberts, RTI International
droberts at rti.org
doug at parrot-farm.net
505-455-7333 - Office
505-670-8195 - Cell

On 4/4/07, Raymond Parks <rcparks at sandia.gov> wrote:

>
> Doug,
>
> You wrote:
> > One will seldom, if ever get identical behavior from two different
> > codes, even if the inputs are identical.
> >
> > The emergent behavior that could be observed from EpiSims, The SIMS, and
> > Second Life, assuming the latter two could emulate responses to the
> > introduction of a viral pathogen, will vary based directly on the
> > differences of granularity with with the agents are implemented in the
> > simulations.
>
>    Given that the "agents" in The Sims and Second Life are avatars for
> real people, one could argue that their code is more realistic than
> agent code.  Their granularity is basically as small as one can get -
> some MMORPGs allow for more than one character per player but they are
> still one character per character.  One problem I can see would be that
> MMORPGs in general suffer from the lack of full participation - EpiSims
> models every second of human behaviour for a large population, but
> MMORPG players are not playing their avatars all of the time.
>
>    I wonder if some combination would play to the strengths of both
> systems.  Could one use something like EpiSims running at wall-clock
> speed as the background for avatars played by real people?  Then the
> simulated people agent code could self-modify on the fly to model the
> behaviour of the real people.  I'm starting to sound like the
> explanation of the fake Rock Ridge in "Blazing Saddles".
>
> --
> Ray Parks                   rcparks at sandia.gov
> IDART Project Lead          Voice:505-844-4024
> IORTA Department            Mobile:505-238-9359
> http://www.sandia.gov/scada Fax:505-844-9641
> http://www.sandia.gov/idart Pager:800-690-5288
>
>
> ============================================================
> 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
>
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One of my projects

Marcus G. Daniels
In reply to this post by Parks, Raymond
I've always disliked the term ABM because the notion of intelligent or
semi-intelligent actors is a distraction.  Really ABM and rule based
modeling are the same thing.  Agents models can be of car engines, etc.

Defined conservatively, say to understand human behavioral patterns in
virtual worlds as opposed to human behaviors in general, it does seem
that human vs. computer agents could be useful to mix and match for
modeling.  Say, to refine models of the range of individual behavioral
patterns for the sake of make predictions of groups of people in yet to
be designed virtual worlds..




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One of my projects

Phil Henshaw-2
Ah, yes... very significant observation.  And then how do you represent the
systems of nature that are out of control and making up altogether new
rules???   And how do you tell which is which?

If you're a real pest for detailed observation you find that our rule making
is always an idealization of a conceptual level of organization in nature,
not the real behavior of nature.    It's tough, but we're stumbling over the
error of representing our ways of predicting events as the mechanism by
which nature performs events.   Its-a just not-a da case!


On 4/4/07, Marcus G. Daniels <marcus at snoutfarm.com> wrote:

>
> I've always disliked the term ABM because the notion of intelligent or
> semi-intelligent actors is a distraction.  Really ABM and rule based
> modeling are the same thing.  Agents models can be of car engines, etc.
>
> Defined conservatively, say to understand human behavioral patterns in
> virtual worlds as opposed to human behaviors in general, it does seem
> that human vs. computer agents could be useful to mix and match for
> modeling.  Say, to refine models of the range of individual behavioral
> patterns for the sake of make predictions of groups of people in yet to
> be designed virtual worlds..
>
>
>
> ============================================================
> 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
>
>
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One of my projects

Marcus G. Daniels
Phil Henshaw wrote:
> how do you represent the systems of nature that are out of control and
> making up altogether new rules???  
At some point that kind effort is less of an empirical science and more
of a mathematical investigation into worlds as they could be.  That's
not to say it is bad, it's just a different goal.

One way to proceed with that kind of investigation is with genetic
programming.  Create an imaginary world that has certain forces acting
on the things in it, and then evolve computer programs that can survive
in that imaginary world.   After the agents survive very well, take
apart those computer programs to try figure out how they work, or study
how different computer programs interact in that world and possibly even
change it.   Classic example:

http://www.archive.org/details/sims_evolved_virtual_creatures_1994

With an avatar/gaming world, it's not hard to imagine automated agents
learning how to fight or cooperate with human players.  Then one could
probe those agents to watch how they make decisions.  To be more
systematic and learn about learning one could have timestamps on each
node/branch to compare the recent innovations from enduring logic.


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One of my projects

Ian P. Cook
NOTE: Apologies if this is duplicated. Got a note back that I used the wrong
email addy on my last attempt, but it's Gmail, so it shows my response in
the chain anyway...

For an instance that may be somewhat akin to what's being discussed here,
I'd refer back to an even from two years ago in the MMORPG World of
Warcraft. A "plague" that was designed by the game programmers and intended
to be restricted to a particular server actually made its way onto other
servers. The plague spread rapidly, producing a fascinating -- to me, anyway
-- array of reactions. More on the issue is here:
http://www.securityfocus.com/news/11330 .

In response to the question "how would the avatars know when they were
infected?", this was actually part of the game: health of the character
decreased incrementally. The plague could be spread, treated but not cured,
cured, etc. What I found most compelling was that the WoW community
responded in many of the same ways as you'd think people would in the face
of a real disaster. Whole neighborhoods banned entrance from unknown
players, some altruistic people went around giving out healing/resurrection
spells  (things that have to be bought with money that is earned through
time playing the game, so not entirely without value), while still others
thought it amusing to spread the virus as far as possible. There were even
debates in various fora about retaining or eliminating the potential for
such an outbreak; that it got out of the hands of the designers enhanced the
realism to some, made the gameplay worse to others. In the wake of the virus
in WoW, I sent the people at Blizzard Entertainment inquiries about getting
anonymized data on various things they track, but got a polite "You must be
joking, right?"

While we often can't run experiments on humans, with the growth of
involvement in games like WoW, Second Life, Eve, etc, would it be impossible
to consider experimenting in these realms? The big mean bad guys in MMORPGS
are rather like agents, so there's already some precedent for mixing the
two. There's a growing study of gameworld macroeconomics, the value of time
people expend in increasing their online holdings (to  the point of "gold
farming" being a big job for kids in urban China and South Korea), and so
on.

-Ian

On 4/4/07, Marcus G. Daniels <marcus at snoutfarm.com> wrote:

>
> Phil Henshaw wrote:
> > how do you represent the systems of nature that are out of control and
> > making up altogether new rules???
> At some point that kind effort is less of an empirical science and more
> of a mathematical investigation into worlds as they could be.  That's
> not to say it is bad, it's just a different goal.
>
> One way to proceed with that kind of investigation is with genetic
> programming.  Create an imaginary world that has certain forces acting
> on the things in it, and then evolve computer programs that can survive
> in that imaginary world.   After the agents survive very well, take
> apart those computer programs to try figure out how they work, or study
> how different computer programs interact in that world and possibly even
> change it.   Classic example:
>
> http://www.archive.org/details/sims_evolved_virtual_creatures_1994
>
> With an avatar/gaming world, it's not hard to imagine automated agents
> learning how to fight or cooperate with human players.  Then one could
> probe those agents to watch how they make decisions.  To be more
> systematic and learn about learning one could have timestamps on each
> node/branch to compare the recent innovations from enduring logic.
>
> ============================================================
> 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
>



--
___________________________________
Ian P. Cook
m: 703.405.0279
h: 703.578.0798
jabber: ianpcook at gmail.com
Y!/MSN: ian_palmer_cook
AIM: ianpalmercook
___________________________________
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One of my projects

Parks, Raymond
In reply to this post by Douglas Roberts-2
Doug,

You wrote:
> Please explain how the "avatars" will know when they have been infected
> by a virus, and how they will respond to that.

   The avatar may or may not know, depending upon the implementation.
The real question is whether the player of the avatar knows.  This is
something that would have to be crafted into the simulation.  Let me
write this up in a logical way.

------------------------------------------------------------------
if the AVATAR is exposed to the disease then
   if the exposure is sufficient then
//(ACPLA > X, transferred virii > 50% infection probability or whatever)
       set the infected flag in the AVATAR
       set incubation time
       start the incubation timer counting to incubation time
   endif
endif

// Player continues to play AVATAR normally
// Ignore infectious incubation periods for now
// Increment incubation timer each second as part of simulation cycle

if the incubation timer is equal to incubation time then
   set the active flag in the AVATAR
   set the disease time
//  This could be to death, to recovery, or other outcome
   start the disease timer counting to disease time
endif

// Then, for each simulation cycle

look up symptoms using disease timer
inform player of AVATAR symptoms
// "You feel tired and your muscles ache."
------------------------------------------------------------------

   The player of the AVATAR should respond in an appropriate way,
probably based on their real-life experience.  Some will ignore the
symptoms until their AVATAR starts functioning poorly (doesn't move as
fast, doesn't notice the bus about to run them down, or whatever).  Some
will promptly go to a doctor.  Some may seek advice from other AVATARs
representing trusted counselors (parents, grandparents, etc).  All of
these will have different effects on the spread of an epidemic and are
not something you would think to model.  That's the point of using real
humans - they do the darndest things that you'd never expect.  If you
don't take those strange actions into account, your sim could give you
an answer that has nothing to do with the real world.

> In fact, please explain how the "avatars" know when go to work,

   How do you know when to go to work?  Somebody told you.  If you have
real humans playing an AVATAR in your simulation, they will have to be
briefed on the role they must play.

   "You're a computer scientist who has to arrive at the lab every
morning at 0830, gets a half hour for lunch somewhere between 1100 and
1300, and may go home at 1700."

> when and where to go shopping,

   "You open the refrigerator to see what you can make for dinner and
there's nothing there."

> know when an epidemic has been announced;

   "You hear the funny honking of the emergency broadcast network on
your car radio.  An announcer says there is an epidemic raging in your
town."

> how they will respond to a decreed intervention strategy of keeping the kids home
> from school?

   "The emergency announcer says you must keep your kids home from school."

   In the type of MMORPG we're talking about, its likely that the kids
are not played by real people but by your agents.  The interaction
between the agents and the parent will drive the actions of the parent
AVATAR's player.  If the simulation informs the parent that their kids
are driving them crazy, the parent may decide not to keep them home from
school.  If the initial briefing informed the role-player that they are
short on money, they may decide not to stay home with the kids or to let
the kids roam freely while the role-player's AVATAR goes to work.

>  What will be the "avatar" level of compliance to the
> declared regime of intervention strategy?  How many will accept
> anti-viral treatment?  How many will wear masks to work?  How many will
> comply to government requests to self-isolate when they become
> symptomatic?

   These are all decisions that the player will make in playing the
AVATAR.  That's the point of using real people to help your simulation
be real.  We would have to design mechanisms to provide the correct
feedback to the player.  You already mentioned that your sim has
provision for poor folks who can't afford not to work.  The player would
just be informed of the same information - "Your rent is due next Friday
and you don't have enough money." - to which the player can either
decide to go to work or to follow orders and stay home.  To get the
reasonable results from the players, the sim needs to provide feedback.
  This doesn't have to be realistic as long as the result is the same.

   MMORPGs have mechanisms to do this type of thing without requiring
every actor be role-played.  In Star Wars Galaxies, certain professions
can "mine" resources - these aren't just minerals.  Rather than play out
the various processes required for mining minerals or growing plants,
the player has to spend time in a certain spot in the game world
clicking on a point or something.  Each click increments the resource
count by a miniscule amount.  The intent is that the AVATAR spends time
in a particular location doing some activity to collect resources.  It's
the spending of time and lack of movement/participation that is the
behaviour to be modeled, not the actions necessary to collect the resources.

> How will an "avatar" determine when it has become
> symptomatic?

   All we can do is tell the player that their AVATAR has certain
symptoms.  Depending upon whether we want to make this easy or not, we
can use the same words as the government request or use different words
that require the player to interpret them - just as a person would have
to interpret their symptoms in a real epidemic.  Some people think they
can't move they ache so badly and others think the muscle ache is a
minor annoyance.  In a straight simulation, you model this with some
sort of normal distribution of how many will comply.  I'm proposing that
we model compliance with real people and then turn around and use that
number in the agents.

> With what level of resolution will these "avatars" behave in the simulation?

   That's the real difficulty.  In effect, we would be federating two
simulations in the same structure, and getting timing to match between
two federated simulations is always a problem.  We have the most control
over the agent simulation - we can run it faster or slower to match the
turn speed we give to the human-played AVATARs.  Fortunately, it isn't
necessary for the human players to enter their actions every second -
they can enter courses of action (go out door - get in car - drive to
work - walk into office - ....) which can then be played out in time to
match the agent simulation.  If the agent sim runs faster than
real-time, we can see if that still matches the COA level of the human
players.  If the agent sim is too fast, we can throttle it back (or add
more agents).  If the agent sim runs too slow, we can coarsen the time
for each turn for the human - instead of asking the human player to
choose what their AVATAR does for the next five minutes, we ask them to
choose for the next ten minutes.

   I'm detecting a certain stridency in your replies.  I hope I'm wrong
and you're not upset at my suggestion.  That's all this is - a
suggestion.  It may not be feasible and I certainly have no stake in
this idea.  It was just something I threw out based on my experience as
a role-playing gamer and my limited knowledge of MMORPGs.

--
Ray Parks                   rcparks at sandia.gov
IDART Project Lead          Voice:505-844-4024
IORTA Department            Mobile:505-238-9359
http://www.sandia.gov/scada Fax:505-844-9641
http://www.sandia.gov/idart Pager:800-690-5288



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One of my projects

Phil Henshaw-2
In reply to this post by Marcus G. Daniels
I mainly just learn to identify islanded causal chains, and by long
experience find that when they result in things I can then replace in my
mind with rules, I'm forced to say that the local system made them up.


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 Marcus G. Daniels
> Sent: Wednesday, April 04, 2007 11:38 PM
> To: The Friday Morning Applied Complexity Coffee Group
> Subject: Re: [FRIAM] One of my projects
>
>
> Phil Henshaw wrote:
> > how do you represent the systems of nature that are out of
> control and
> > making up altogether new rules???  
> At some point that kind effort is less of an empirical
> science and more
> of a mathematical investigation into worlds as they could be.  That's
> not to say it is bad, it's just a different goal.
>
> One way to proceed with that kind of investigation is with genetic
> programming.  Create an imaginary world that has certain
> forces acting
> on the things in it, and then evolve computer programs that
> can survive
> in that imaginary world.   After the agents survive very well, take
> apart those computer programs to try figure out how they
> work, or study
> how different computer programs interact in that world and
> possibly even
> change it.   Classic example:
>
http://www.archive.org/details/sims_evolved_virtual_creatures_1994

With an avatar/gaming world, it's not hard to imagine automated agents
learning how to fight or cooperate with human players.  Then one could
probe those agents to watch how they make decisions.  To be more
systematic and learn about learning one could have timestamps on each
node/branch to compare the recent innovations from enduring logic.

============================================================
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





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One of my projects

Douglas Roberts-2
In reply to this post by Parks, Raymond
Hey, Ray.

No, I'm not upset.  I believe the original question was (paraphrasing)
"Wouldn't an avatar-based system produce more accurate epidemiological
simulation results than other agent based models, such as EpiSims?"

The point of the questions that I blasted back at you was to illustrate that
the resolution of the disease representation, and the characterization of
disease progression in the individuals in a population is as important, if
not more so that the ability to simulate any human decision-making behavior
(which presumably would be your motivation for suggesting an avatar-based
approach).  A population is comprised of old, young, immuno-suppressed, and
"normal" healthy individuals.  Any particular disease will propagate at
different rates, with different individual responses when it is attacking
the population.  An avatar-based simulation would not be any better
representing at that than any agent-based simulation would be.

Equally important to fidelity in representation of the disease impact on
individual members of the population, and on the population as a whole is
the fidelity of representation of the population mobility patterns in the
system being modeled.  Disease such as influenza is spread by contact, and
if you don't have accurate representations of the population mobility
patterns, your results will be meaningless.   An avatar-based simulation
would probably  be *much* worse at modeling population contact patterns than
a simulation such as EpiSims, Epicast, or a number of other population
mobility-based simulations, because the population mobility patterns in
those simulations are at least validated.

The whole precept of avatar-based simulations is that with such, you
supposedly get better representations of human decision processes.  I don't
believe that.  And in particular, I don't believe it when it comes to
modeling large complex urban areas in which a biological agent is discovered
to have been introduced into the system.

--Doug

--
Doug Roberts, RTI International
droberts at rti.org
doug at parrot-farm.net
505-455-7333 - Office
505-670-8195 - Cell

On 4/5/07, Raymond Parks <rcparks at sandia.gov> wrote:

>
> Doug,
>
> You wrote:
> > Please explain how the "avatars" will know when they have been infected
> > by a virus, and how they will respond to that.
>
>    The avatar may or may not know, depending upon the implementation.
> The real question is whether the player of the avatar knows.  This is
> something that would have to be crafted into the simulation.  Let me
> write this up in a logical way.
>
> ------------------------------------------------------------------
> if the AVATAR is exposed to the disease then
>    if the exposure is sufficient then
> //(ACPLA > X, transferred virii > 50% infection probability or whatever)
>        set the infected flag in the AVATAR
>        set incubation time
>        start the incubation timer counting to incubation time
>    endif
> endif
>
> // Player continues to play AVATAR normally
> // Ignore infectious incubation periods for now
> // Increment incubation timer each second as part of simulation cycle
>
> if the incubation timer is equal to incubation time then
>    set the active flag in the AVATAR
>    set the disease time
> //  This could be to death, to recovery, or other outcome
>    start the disease timer counting to disease time
> endif
>
> // Then, for each simulation cycle
>
> look up symptoms using disease timer
> inform player of AVATAR symptoms
> // "You feel tired and your muscles ache."
> ------------------------------------------------------------------
>
>    The player of the AVATAR should respond in an appropriate way,
> probably based on their real-life experience.  Some will ignore the
> symptoms until their AVATAR starts functioning poorly (doesn't move as
> fast, doesn't notice the bus about to run them down, or whatever).  Some
> will promptly go to a doctor.  Some may seek advice from other AVATARs
> representing trusted counselors (parents, grandparents, etc).  All of
> these will have different effects on the spread of an epidemic and are
> not something you would think to model.  That's the point of using real
> humans - they do the darndest things that you'd never expect.  If you
> don't take those strange actions into account, your sim could give you
> an answer that has nothing to do with the real world.
>
> > In fact, please explain how the "avatars" know when go to work,
>
>    How do you know when to go to work?  Somebody told you.  If you have
> real humans playing an AVATAR in your simulation, they will have to be
> briefed on the role they must play.
>
>    "You're a computer scientist who has to arrive at the lab every
> morning at 0830, gets a half hour for lunch somewhere between 1100 and
> 1300, and may go home at 1700."
>
> > when and where to go shopping,
>
>    "You open the refrigerator to see what you can make for dinner and
> there's nothing there."
>
> > know when an epidemic has been announced;
>
>    "You hear the funny honking of the emergency broadcast network on
> your car radio.  An announcer says there is an epidemic raging in your
> town."
>
> > how they will respond to a decreed intervention strategy of keeping the
> kids home
> > from school?
>
>    "The emergency announcer says you must keep your kids home from
> school."
>
>    In the type of MMORPG we're talking about, its likely that the kids
> are not played by real people but by your agents.  The interaction
> between the agents and the parent will drive the actions of the parent
> AVATAR's player.  If the simulation informs the parent that their kids
> are driving them crazy, the parent may decide not to keep them home from
> school.  If the initial briefing informed the role-player that they are
> short on money, they may decide not to stay home with the kids or to let
> the kids roam freely while the role-player's AVATAR goes to work.
>
> >  What will be the "avatar" level of compliance to the
> > declared regime of intervention strategy?  How many will accept
> > anti-viral treatment?  How many will wear masks to work?  How many will
> > comply to government requests to self-isolate when they become
> > symptomatic?
>
>    These are all decisions that the player will make in playing the
> AVATAR.  That's the point of using real people to help your simulation
> be real.  We would have to design mechanisms to provide the correct
> feedback to the player.  You already mentioned that your sim has
> provision for poor folks who can't afford not to work.  The player would
> just be informed of the same information - "Your rent is due next Friday
> and you don't have enough money." - to which the player can either
> decide to go to work or to follow orders and stay home.  To get the
> reasonable results from the players, the sim needs to provide feedback.
>   This doesn't have to be realistic as long as the result is the same.
>
>    MMORPGs have mechanisms to do this type of thing without requiring
> every actor be role-played.  In Star Wars Galaxies, certain professions
> can "mine" resources - these aren't just minerals.  Rather than play out
> the various processes required for mining minerals or growing plants,
> the player has to spend time in a certain spot in the game world
> clicking on a point or something.  Each click increments the resource
> count by a miniscule amount.  The intent is that the AVATAR spends time
> in a particular location doing some activity to collect resources.  It's
> the spending of time and lack of movement/participation that is the
> behaviour to be modeled, not the actions necessary to collect the
> resources.
>
> > How will an "avatar" determine when it has become
> > symptomatic?
>
>    All we can do is tell the player that their AVATAR has certain
> symptoms.  Depending upon whether we want to make this easy or not, we
> can use the same words as the government request or use different words
> that require the player to interpret them - just as a person would have
> to interpret their symptoms in a real epidemic.  Some people think they
> can't move they ache so badly and others think the muscle ache is a
> minor annoyance.  In a straight simulation, you model this with some
> sort of normal distribution of how many will comply.  I'm proposing that
> we model compliance with real people and then turn around and use that
> number in the agents.
>
> > With what level of resolution will these "avatars" behave in the
> simulation?
>
>    That's the real difficulty.  In effect, we would be federating two
> simulations in the same structure, and getting timing to match between
> two federated simulations is always a problem.  We have the most control
> over the agent simulation - we can run it faster or slower to match the
> turn speed we give to the human-played AVATARs.  Fortunately, it isn't
> necessary for the human players to enter their actions every second -
> they can enter courses of action (go out door - get in car - drive to
> work - walk into office - ....) which can then be played out in time to
> match the agent simulation.  If the agent sim runs faster than
> real-time, we can see if that still matches the COA level of the human
> players.  If the agent sim is too fast, we can throttle it back (or add
> more agents).  If the agent sim runs too slow, we can coarsen the time
> for each turn for the human - instead of asking the human player to
> choose what their AVATAR does for the next five minutes, we ask them to
> choose for the next ten minutes.
>
>    I'm detecting a certain stridency in your replies.  I hope I'm wrong
> and you're not upset at my suggestion.  That's all this is - a
> suggestion.  It may not be feasible and I certainly have no stake in
> this idea.  It was just something I threw out based on my experience as
> a role-playing gamer and my limited knowledge of MMORPGs.
>
> --
> Ray Parks                   rcparks at sandia.gov
> IDART Project Lead          Voice:505-844-4024
> IORTA Department            Mobile:505-238-9359
> http://www.sandia.gov/scada Fax:505-844-9641
> http://www.sandia.gov/idart Pager:800-690-5288
>
>
> ============================================================
> 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
>
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human/computer simulated environments

Marcus G. Daniels
In reply to this post by Parks, Raymond
For any virtual sociologists out there.. second Life is being open sourced!

http://blogs.zdnet.com/social/?p=142