Hi everyone,
Has anyone tried to calculate number of reinforcing or balancing loops passing a specific variable in a system?
I have built a conceptual model and identified some key variables. I now want to check whether reinforcing loops or balancing loops dominate that variable, however there are too many loops involved that variable (~200 loops). It seems impossible to manually count every single loop to identify either reinforcing or balancing for about 5 variables as it will come up about 1000 loops.
Is there any way we can know a loop belongs to reinforcing or balancing without counting everylink relating a variable?
I appreciate any comment or suggestion.
Regards,
Thanh
Help please-Calculating number of reinforcing/balancing loops passing a variable in VENSIM PLE
Re: Help please-Calculating number of reinforcing/balancing loops passing a variable in VENSIM PLE
You can use the loops tool to count the total number of loops, but not their polarity.
Can you describe your purpose for doing this?
I think what you may really need is eigenvector analysis: https://pdfs.semanticscholar.org/58b4/c ... 845f28.pdf
Can you describe your purpose for doing this?
I think what you may really need is eigenvector analysis: https://pdfs.semanticscholar.org/58b4/c ... 845f28.pdf
/*
Advice to posters (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Blog: http://blog.metasd.com
Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
*/
Advice to posters (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Blog: http://blog.metasd.com
Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
*/
Re: Help please-Calculating number of reinforcing/balancing loops passing a variable in VENSIM PLE
Hi tomfid, Thanks for your rep.
The purpose of counting number of reinforcing and balancing loops for a particular variable is to identify which type of loop dominate that variable.
Then I can qualitatively assess the system behaviour/stability one I have know dominance loops for key variables.
Should this your company develop an add-on function to VENSIM in the near future?
I could not download the pdf file, could you please re-send it. Thank you
Regards,
Thanh
The purpose of counting number of reinforcing and balancing loops for a particular variable is to identify which type of loop dominate that variable.
Then I can qualitatively assess the system behaviour/stability one I have know dominance loops for key variables.
Should this your company develop an add-on function to VENSIM in the near future?
I could not download the pdf file, could you please re-send it. Thank you
Regards,
Thanh
Re: Help please-Calculating number of reinforcing/balancing loops passing a variable in VENSIM PLE
Unfortunately knowing the number of loops isn't helpful, because many weak loops could be dominated by one strong loop.
You might try this link instead: https://papers.ssrn.com/sol3/papers.cfm ... id=3114407
You might try this link instead: https://papers.ssrn.com/sol3/papers.cfm ... id=3114407
/*
Advice to posters (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Blog: http://blog.metasd.com
Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
*/
Advice to posters (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Blog: http://blog.metasd.com
Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
*/
Re: Help please-Calculating number of reinforcing/balancing loops passing a variable in VENSIM PLE
This is something we're exploring but it's not on the road map yet.
/*
Advice to posters (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Blog: http://blog.metasd.com
Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
*/
Advice to posters (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Blog: http://blog.metasd.com
Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
*/
Re: Help please-Calculating number of reinforcing/balancing loops passing a variable in VENSIM PLE
/*
Advice to posters (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Blog: http://blog.metasd.com
Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
*/
Advice to posters (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Blog: http://blog.metasd.com
Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
*/
Re: Help please-Calculating number of reinforcing/balancing loops passing a variable in VENSIM PLE
Thank you,
I will read those refs.
I will read those refs.