***** To join INSNA, visit http://www.insna.org *****
There is a reasonably long history of work on dynamic networks, and a
couple of choices of free public software now available as well.
Two you should consider are Tom Snijder's StOCNET/Sienna packages, and the
new "statnet" package from the UW network modeling group. Snijder's
package uses a windows menu driven interface, so is very easy to work
with. "statnet" uses the stat package R as an interface, so is works on
all platforms. it's also more flexible and capable of handling larger
networks, but there is a steeper learning curve if you're not already
familiar with R.
Both come up first in a google search now, so are easy to find.
best,
Martina Morris
On Thu, 20 Jul 2006, David Krackhardt wrote:
> ***** To join INSNA, visit http://www.insna.org *****
>
> Roy (and Chai Choon-Lee),
>
> Interesting alternative. I've been a fan of the systems dynamics models for
> years. But, I am reminded of two things. First, the most robust general
> finding of the systems dynamics literature is that it is the structure (the
> existence of feedback loops), not the flows or rates, that make a substantial
> difference in the behavior of the model. This is where SNA can shine. SD
> assumes a structure and simulates a result. SNA can actually explain
> (predict) the structure, leading to insights into why the critical feedback
> loops exist (perhaps stochastically). It can also lead more efficiently to
> insights about critical nodes (centrality, structural holes, etc.) as a
> function of the structure.
>
> This, however, does not take away from your primary point: SNA more often
> than not deals with fixed stationary, not dynamic, models. Which brings me
> to my second thought: Some networkers have combined both the structural
> orientation of SNA and the dynamic orientation of simulations. Foremost
> among these is Kathleen Carley, in my view. She has several large scale
> packages that are built around and calculate network concepts but also use
> agent modeling techniques to simulate dynamics. One advantage to her work is
> that she permits the structure itself to be dynamic, depending on the rules
> that govern the formation and dissolution of network links. I would
> recommend considering some of her packages in addition to the MIT-based SD
> software. You can find out more about these at her CASOS website; or, since
> she produces stuff so fast I am not sure the website can keep up, perhaps you
> are better off asking her directly ([log in to unmask]).
>
> -David
>
>
>
> --On Thursday, July 20, 2006 9:11 AM +0100 Roy Greenhalgh <[log in to unmask]>
> wrote:
>
>> ***** To join INSNA, visit http://www.insna.org *****
>>
>> Dear Chai Choon-Lee
>>
>> I would recommend that, rather than pursue an SNA solution (if there is
>> one), you look at System Dynamics. This explores the dynamics of flows
>> and the accumulation and dissipation of resources (or stocks as they are
>> called) over time. You indicate this is what you are wanting to do.
>>
>> There are a number of sftware packages: Stella or IThink, Vensim, and
>> Powersim are the most popular: the first two are basically the same
>> product, but are aimed at the schools/education market and the commercial
>> market respectively. There are student and run-time only versions from
>> publisher's web sites.
>>
>> THE text at present is Sterman. J, 2000,"Business Dynamics: Systems
>> Thinking and Modelling for a Complex World", McGraw-Hill. A more
>> approachable text is Maani, K. E. and Cavana, R. Y., 2003, "System
>> Thinking and Modelling", Pearson Education. Both books come with CDs
>> holding models in the various s/w packages as well as run-time versions
>> of the software.
>>
>> And I would recommend, even though it is designed for K12 schools in the
>> US, the site www.clexchange.org. This has some superb introductory
>> papers, and models showing "simulation" possibly to undergrad level.
>>
>> Then you can make an informed decision!
>>
>> Best wishes ..
>>
>>
>> Roy Greenhalgh
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> Quoting Chai Choon-Lee <[log in to unmask]>:
>>
>>> ***** To join INSNA, visit http://www.insna.org *****
>>>
>>> Hello,
>>>
>>> I am new to SNA. I am working on an engineering project that studies the
>>> interdependency among critical infrastructures, such as electricity,
>>> water, hospital, telecommunication, power plants, etc. I am exploring
>>> the possibility
>>> of using SNA software to simulate infrastructure interdependency.
>>>
>>> Infrastructure interdependency gives rise to an infrastructure
>>> network. In this
>>> project, apart from studying the structural characteristics of
>>> infrastructure network, such as centrality etc., I am wondering if there
>>> is any SNA software that can be used to simulate, for instance, the
>>> material/info/energy flows between infrastructures during an
>>> emergency/disaster situation?
>>>
>>> From my shallow reading of SNA, I get a sense that SNA deals less
>>> with dynamic
>>> situations where different variables change as time goes by. For
>>> instance, in a
>>> disaster situation, medical supplies/hospital beds/food, etc. run down
>>> as the clock ticks, can we use SNA software to simulate this?
>>>
>>> Sorry if my questions sound silly. Thank you for your time.
>>>
>>> Sincerely,
>>>
>>> Choon-Lee Chai
>>> Dept of Sociology
>>> University of Saskatchewan
>>>
>>> _____________________________________________________________________
>>> SOCNET is a service of INSNA, the professional association for social
>>> network researchers (http://www.insna.org). To unsubscribe, send
>>> an email message to [log in to unmask] containing the line
>>> UNSUBSCRIBE SOCNET in the body of the message.
>>>
>>
>> _____________________________________________________________________
>> SOCNET is a service of INSNA, the professional association for social
>> network researchers (http://www.insna.org). To unsubscribe, send
>> an email message to [log in to unmask] containing the line
>> UNSUBSCRIBE SOCNET in the body of the message.
>>
>
>
>
> --------------
> David Krackhardt, Professor of Organizations, editor of JoSS
> Heinz School of Public Policy and Management, and
> The Tepper School of Business
> Carnegie Mellon University
> Pittsburgh, PA 15213
> 412-268-4758
> website: www.andrew.cmu.edu/~krack
> (Erdos#=2)
>
> _____________________________________________________________________
> SOCNET is a service of INSNA, the professional association for social
> network researchers (http://www.insna.org). To unsubscribe, send
> an email message to [log in to unmask] containing the line
> UNSUBSCRIBE SOCNET in the body of the message.
>
****************************************************************
Director
Center for Studies in Demography and Ecology
Box 353412
University of Washington
Seattle, WA 98195-3412
Office: (206) 685-3402
Dept Office: (206) 616-7743
Fax: (206) 616-8135
http://csde.washington.edu/
[log in to unmask]
http://faculty.washington.edu/morrism/
_____________________________________________________________________
SOCNET is a service of INSNA, the professional association for social
network researchers (http://www.insna.org). To unsubscribe, send
an email message to [log in to unmask] containing the line
UNSUBSCRIBE SOCNET in the body of the message.
|
