Ventana software support forum

Simplifier

Administrator wrote: ↑Thu Sep 23, 2021 6:32 am You can load both of them, or edit using a text editor and copy/paste the contents of one into the other.

It worked well, thanks.

Simplifier

I have two different files with '.out' kind that contain two sets of calibrated constants values. I want to combine and use as one file in order to run a sensitivity analysis for my model.

Can someone advise please?

Simplifier

How can I type the name of a variable using subscripts and superscripts like in Word Microsoft? The Editor only allows me to type letters in one line.

Simplifier

I think the answer depends on whether the scenarios differ only in terms of future policy, or also past variables that would affect the fit to history. Normally I would think of there being a single baseline, with policy scenarios varying around that. The way to implement this is to calibrate the m...

Simplifier

I have calibrated the baseline scenario in my model and I have established two more possible scenarios. Does the software need to recalibrate and re-estimate constants based on the two new scenarios or it only needs to run simulation for them using the baseline estimations?

Simplifier

Administrator wrote: ↑Thu May 21, 2020 11:44 am If you email us with your serial number, I can give you access to the 8.1 installer (which should make this problem go away).

I just sent you an email with my serial number.

Simplifier

Administrator wrote: ↑Thu May 21, 2020 7:03 am Is this on Mac or Windows?

This is on Mac with the OS Catalina, and by the way my Vensim is DSS Professional version 8.0.9 X64.

Simplifier

Sometimes at the end of my simulation or optimisation runs I'm getting the warning "Bad indirect CWP1322". I have to close and reopen my model so I can be able to click and open the options panels or rum my simulation or optimisation.

Can you tell me what the warning refers to?

Simplifier

I have thousands of parameters connected to one another in my model, and when I started building them up and made the connections between them with arrows, I was not much concerned about the aesthetic aspect of the model. Now I can see a big dish of spaghetti which makes it hard for the readers to u...

Simplifier

The rule of thumb for 1/3 the smallest delay is reasonable, but sometimes not sufficient. Really the rule should be 1/3 the shortest effective time constant, whether it is in a negative or positive loop, and this is not always known. The simplest thing to do is do some testing - lower the time step...

Simplifier

Thanks for your clear, helpful explanation. As long as we are on the time subject, I was wondering what adjustment time or delay means in a model and why we have to consider it while choosing the time step? Since I've been told the time step I select should be 1/3 of the smallest delay in my model. ...

Simplifier

The initial and final time in my model is 1985 and 2016, and I have set TIME STEP to 0.0625. I am using RANDOM PINK NOISE function which contains correlation time. Since I want the picked up data to have a path dependency behaviour of six months, should I put 0.5 (i.e. half a year) as correlation or...

Simplifier

Administrator wrote: ↑Fri Apr 10, 2020 1:50 pm You are getting into problems as there is an error in your model. Run it (not optimize) and then look at the graph for "Bev Scientific Knowledge Development Stock". Is that correct?

Thanks very much.

Yes you are right!

Simplifier

I'm trying to optimise my model but the simulation run get stuck into the notification ""setting up the simulation" with no run.

I have attached the model here.

Could you please help me with the issue?

Simplifier

If you think about a run with 4 time steps, the random draws might be Time 1 2 3 4 Value 3 8 2 6 If you halve the time step, you get Time 0.5 1 1.5 2 2.5 3 3.5 4 Value 3 8 2 6 1 7 7 9 The value 2 now occurs at time 1.5 instead of time 2, etc. In a real model, it's more complex than that, because yo...

Simplifier

I'd suggest putting in some realistic bounds on the things you are allowing the optimizer to modify, if you do this, the optimal solution is identical for time step = 0.5 and 0.03125. I put some realistic bounds. The eventual results seem identical, though not entirely. Why does the outcome of pink...

Simplifier

Administrator wrote: ↑Mon Mar 30, 2020 10:44 am If you upload the model, we can take a look. Make sure you upload all files required to run it.

Simplifier

Have I observed and detected a right reason for it?? What's your recommendation to fix it? As I've suggested, you should fix all the units errors in your model first. This will lead you to where all the errors are. I have created a new small, simple model and I have used a pink noise in it. Again w...

Simplifier

The best thing to do is create some custom graphs that compare the model to the data, and then do some hand calibration to see what's going on. I think I figured what the issue can be. I'm using several RANDOM PINK NOISE functions in my model and it seems they are really sensitive to the change of ...

Simplifier

Since the historical data tat I am using to optimise and calibrate my model has been collected annually, should I define the TIME STEP annually too? Because the smaller TIME STEP that I use, the worse the optimisation payoff I obtain for the model.

Simplifier

I don't think the SSD will matter much for optimizations, because it's not writing much data until the end. I didn't notice in your first post that it was a Ryzen 7. This could be an AMD/Intel difference. Historically, AMDs had more cores, but Intels were about twice as fast per core. I thought the...

Simplifier

Administrator wrote: ↑Fri Mar 27, 2020 9:18 am Please do (vensim@vensim.com).

Thanks.

I just sent all the files.

Simplifier

Since my model was being optimised really slowly on my MacBook air (Macintosh with CPU Core i5 1.6Ghz , and 4 GB Ram), for example each simulation run would take at least 5 secs, I purchased a very powerful PC (Windows with CPU AMD Ryzen 7 (3700X) 8 core, and 32 GB Ram) so I could accelerate the op...

Simplifier

tomfid wrote: ↑Fri Mar 27, 2020 3:56 am There shouldn't be much difference from the OS. Any chance you were running compiled on the Mac?

Any other recommendation Tom?

Simplifier

tomfid wrote: ↑Fri Mar 27, 2020 3:56 am There shouldn't be much difference from the OS. Any chance you were running compiled on the Mac?

I dont exactly know what compiling means in this particular situation, but I am doing the same process, borrowing the different required files from their sources individually.

Ventana software support forum

Search found 54 matches

Re: How to combine two .out files?

How to combine two .out files?

Typing the name of a variable using subscripts and superscripts

Re: Calibrating various scenarios beside the baseline

Calibrating various scenarios beside the baseline

Re: Warning "Bad indirect CWP1322"

Re: Warning "Bad indirect CWP1322"

Warning "Bad indirect CWP1322"

Any built-in options to relocate and re-layout the parameters places?

Re: Confusion about the correlation time unit in RANDOM PINK NOISE funtion

Re: Confusion about the correlation time unit in RANDOM PINK NOISE funtion

Confusion about the correlation time unit in RANDOM PINK NOISE funtion

Re: Notification "Setting up the simulation"

Notification "Setting up the simulation"

Re: TIME STEP and historical data

Re: TIME STEP and historical data

Re: TIME STEP and historical data

Re: TIME STEP and historical data

Re: TIME STEP and historical data

TIME STEP and historical data

Re: Low optimisation speed

Re: Low optimisation speed

Re: Low optimisation speed

Re: Low optimisation speed

Re: Low optimisation speed