Hi,
I am a new user of Vensim. I would like to model Birth rate to be a variable type with time as we model in stella. Image file attached.
Similar to the below one:
Population(t) = Population(t - dt) + (Births) * dt
INIT Population = 1000
INFLOWS:
Births = Population*Birth_Rate
Birth_Rate = GRAPH(TIME)
(2016, 0.0802), (2017, 0.0849), (2019, 0.0894), (2020, 0.0939), (2022, 0.0986), (2023, 0.103), (2024, 0.108), (2026, 0.113), (2027, 0.118), (2029, 0.123), (2030, 0.127)
Can someone help me in modelling this in vensim. I am also confused on how to do this using lookup variable type.
Modelling Birth Rate to be a variable with time
Modelling Birth Rate to be a variable with time
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Re: Modelling Birth Rate to be a variable with time
It might be best if you visit the following page as they have a really good PLE tutorial. It will teach you all you need to do this.
http://www.public.asu.edu/~kirkwood/sysdyn/SDRes.htm
http://www.public.asu.edu/~kirkwood/sysdyn/SDRes.htm
Advice to posters seeking help (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Units are important!
http://www.bbc.co.uk/news/magazine-27509559
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Units are important!
http://www.bbc.co.uk/news/magazine-27509559
Re: Modelling Birth Rate to be a variable with time
Thanks. I got to know how to do from one of your links. "Vensim PLE Quick Reference and Tutorial". Time has to be shadow variable.
Re: Modelling Birth Rate to be a variable with time
https://vensim.com/lookups-in-vensim/ might be helpful.
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Re: Modelling Birth Rate to be a variable with time
/*
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
*/