Level or Simultaneous Function?

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aalto-comnet
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Level or Simultaneous Function?

Post by aalto-comnet »

Hello!

I am receiving a simultaneous equation error due to the fact that part of my model is about modelling behavior and the loops do not involve any stocks. This can be solved either by turning one of the variables to Level or with the Simultaneous function. The thing is, which one should I choose?

Is a Level variable supposed to be only for stocks? In the link below, it is stated that Levels are also called accumulations, stocks, and states. Could it be a behavioral state as well then?

https://www.vensim.com/documentation/in ... ?21995.htm

If turning a variable into Level is not the correct approach for my model, which of the variables of my model should be turned to Auxiliary Simultaneous, with what initial value, and why?

Attached my (draft) model.

Thank you!
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Re: Level or Simultaneous Function?

Post by Administrator »

Definitely a level here. Hunger will increase with time, and decrease as a result of eating.
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aalto-comnet
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Re: Level or Simultaneous Function?

Post by aalto-comnet »

Hi! Thanks for replying! So, as far as I understand, levels can be used even if we are not accumulating tangible items, right? In order to model, for example, various behavioral aspects.
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Re: Level or Simultaneous Function?

Post by Administrator »

Yes. Hunger can be treated like a level, just like say morale could be for an army.
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
aalto-comnet
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Posts: 37
Joined: Fri Dec 07, 2018 9:20 am
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Re: Level or Simultaneous Function?

Post by aalto-comnet »

Thanks for clarifying! :)
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