Hi,
Could anyone please explain how DELAY1 is different than DELAY3 logically?..or how can I justify that I use DELAY3 but not DELAY1 in my model?..
I know that DELAY 3 takes it as if there are 3 stocks...I wonder how we decide delay3 is more suitable for our model?
Is it because of time step should be smaller than 1/4 of the shortest time in the model?
Thanks in advance..
Nesli
continuous delay
Re: continuous delay
The key difference is in the distribution of arrivals that the two versions imply, so this is really a question to be answered by comparison with data.
You might play with my delay sandbox to get some intuition.
http://models.metasd.com/delay-sandbox/
You might play with my delay sandbox to get some intuition.
http://models.metasd.com/delay-sandbox/
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Re: continuous delay
Hello after a long time,
Is there any example on how to use DELAY information functions as a link/file or etc.
I find it confusing to decide which delay function (order of it) to use in my model...
Thanks
Is there any example on how to use DELAY information functions as a link/file or etc.
I find it confusing to decide which delay function (order of it) to use in my model...
Thanks
Re: continuous delay
There's a sample model linked to every function in the Help system (for example, http://www.vensim.com/documentation/fn_delay3.htm).
Also, http://models.metasd.com/delay-sandbox/.
Other than that, I'd take a look at a good text, like Business Dynamics.
Also, http://models.metasd.com/delay-sandbox/.
Other than that, I'd take a look at a good text, like Business Dynamics.
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Re: continuous delay
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Re: continuous delay
Hi,
there is a nice article by Margret S. Hamilton in Randers' "Elements of the System Dynamics Method" (1980) about how to estimate Delays. Since exponential delays can be linked to the Erlang-Distribution (via convolution) one can build upon this.
I have build a small Mathematica-based tool to do this which can be found with some remarks in the SD forum: Higher Order Delays.
Regards,
Guido
there is a nice article by Margret S. Hamilton in Randers' "Elements of the System Dynamics Method" (1980) about how to estimate Delays. Since exponential delays can be linked to the Erlang-Distribution (via convolution) one can build upon this.
I have build a small Mathematica-based tool to do this which can be found with some remarks in the SD forum: Higher Order Delays.
Regards,
Guido