Ventana software support forum

Thank you so much for your suggestion.

Dear Administrator,

For all Vensim configurations (PLE/PLP), model components (especially text) in the Sketch drawing area is blur. This occurs every time, even in different PCs (Windows 7). To solve this problem, I minimize the window and then maximize it. Could you help?

Best regards,
Monte

Alternatively, you can convert the help file (Vensim.chm), which is installed at the directory C:\Users\Public\VensimPLP\, to be a PDF file, by using an online convertor, e.g., SAMSAR. The major advantages of this option are as follows: 1. The front size is much bigger. 2. All Help chapters are prin...

Dear Tony,

Thank you very much. Hopefully there will be good news soon.

Best regards,
Monte

Dear Tony,

Are you going to have Vensim (all editions) on sale (20% off) this year?

Best regards,
Monte

Thank you.

Hi JJ, Last year I took a course on Kepner and Tregoe's systematic problem solving and decision making, which makes me know an approach that guarantees implementation, e.g., Potential Problem Analysis, which leads to preventive actions and contingent actions. "No matter what might happen, the s...

Hi JJ, Thank you for sharing your ideas. SD CAPABILITY At this moment, I tend to believe that SD can describe any dynamic problem conceptually, and cannot describe some problems numerically. By conceptually, I mean we can build a conceptual model (e.g., stock-flow diagram) of any dynamic problem. As...

Thank you for your reply and questions. The term modeling purpose is not a jargon nor standard concept of the SD paradigm. I coined this word so that we can make a distinction between the obvious purpose (model purpose) and the subtle purpose (modeling purpose). The former is a statement of the util...

Hello JJ, You considered my model purpose. However, there are more to consider. Modelers would state their model purposes (for what the model is intended) very clearly, but rarely do they state their modeling purposes (why they build the models) My modeling purpose is to make a history together. I a...

Thank you, JJ. Initially I was testing the belief, to see if the population of Heaven souls is depleting as stated in the scripture. The testing turns out to be very difficult, as told by the Buddha himself, because of the vast difference between the biggest and smallest values of delays, which caus...

Thank you. If Vensim cannot help, I cannot think of other package that can help. I am thinking of a new way to dealing with such an extreme delay. It is not a good way, but a necessary one if nobody can think of other good or better solutions. I would alter the SD paradigm, in parameter estimation ....

DYNAMIC HYPOTHESIS OF THE THREE WORLDS MODEL People in many far eastern countries hold a common religious belief that they are in a universe of three connecting worlds: the Earth, the Heaven, and the Hell, where living things consist of human and non-human creatures who have been and will be travel...

What is a good way to dealing with the Floating Point error? My model has long delay and short delay constants. The time horizon is [0, 3.3e+170] years. The smallest delay is 100 years, and the largest is 2.772e+034 years. The model purpose is to test a religious belief of reincarnation, long held i...

Thank you.

The 1/(2*2*2*2*2*2*2) tine step is exactly used in my model, and the smallest time step offered by Vensim. To change the model unit from Month to Day, and use the 0.25 Time Step would be the only choice to avoid the error although the senior officer and model users may be more familiar with Monthly ...

Thank you so much. I am reluctant to extend the duration greater than DT, i.e. DT + days. Vensim doesn't treat 1 day as 1/30 month. I don't know the logic behind that. A week would be much longer than the real event's delay. The outflow is of DELAY FIXED. I will study from your suggestion. Thanks ag...

Dear Tom,

Thank you very much for your time and effort.
The rate is not used elsewhere in the model,
but I feel unhappy when seeing the unrealistic behavior (necessarily high rate) in my model
although it already serves the model purpose.

Best regards,
MK

Thank you very much for your correction and clarification.

Dear Administrator, I am writing a research report on SD modeling, and would like to cite good reasons why I used Vensim as a simulation environment. One of them is that Vensim offers discount for governmental (Public Research) use (as shown in attachment). My question: Should I specify the price of...

You may find some answer from this link:
http://public.wsu.edu/~forda/Stella%20o ... 202010.pdf
and Chapter 2 of Ford's Modeling the Environment.

I think Aux cannot use itself because it is not an accumulation. It uses information from other variables/parameters, not the material you think it had accumulated but actually it has never done. It doesn't conserve mass, its present value does not depend on its part values. So A(T) = A(T-1) + .... ...

I have revised the rate equation as attached. The task force is formed quickly after they are ordered (one time step). I extract the PULSE function out, to be a new variable called Task Force Formation Policy . The rate represents the policy to start a task force formation and the target task force....

Thank you for your answer. I am going to split and simplify the rate equation, to find a new structure with real world equivalents. The original equation is somewhat analytical and hard to explain clearly as you pointed out.

The question is...Have you ever seen an unrealistic rate behavior used
for generating a reasonable level behavior like this?
Is it a good modeling practice?

In my opinion, if the rates are not used elsewhere in the model, this practice might be okay.