DELAY FIXED

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viladent
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Joined: Sun Sep 18, 2005 2:53 pm

DELAY FIXED

Post by viladent »

Hi,
I am trying to set a Delay Fixed between a population aged 0-1 and a population aged 16-20, so I have entered a 192 month delay and an initial value of population 0-1 at 40000 as it should be but I obtain graphs with high and negative values. I know the rest of the model is working as I tried it before with several reservoirs between 0-1 and 16-20 instead of a Delay Fixed.
What did I do wrong with Delay Fixed?
Thanks
Administrator
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Post by Administrator »

Can you give us the part of the model that is not working? It is probably a very simple fix.

Tony.
viladent
Junior Member
Posts: 11
Joined: Sun Sep 18, 2005 2:53 pm

Post by viladent »

Originally posted by Administrator
Can you give us the part of the model that is not working? It is probably a very simple fix.

Tony.
Actually I entered a Delay fixed such as "0-1", 192, 42500 as the reservoir 0-1 is currently at 42500, reservoir 16-20 is at 34000 as 80% of the persons in 0-1 will enter 16-20 192 month later, when I do a simulation on 300 months I obtained graphs with negative values for both reservoirs 0-1 and 16-20, the other part s of the models are OK
Thank you
Chris
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Post by Administrator »

I really need to see a model here. Can you copy the part that is giving negative results into a new model, get that running so that it produces the error and then post it here?

Tony.
viladent
Junior Member
Posts: 11
Joined: Sun Sep 18, 2005 2:53 pm

Post by viladent »

Originally posted by Administrator
I really need to see a model here. Can you copy the part that is giving negative results into a new model, get that running so that it produces the error and then post it here?

Tony.
Hi Tony.
sorry, I cannot really keep up to speed with the forum due to the time difference. I really appreciate your efforts to support a beginer as I am. I have reproduced a fragment of the model with the reservoirs which give the negative number.
Best regards
Christian
Attachments
age effect (mock up).mdl
(3.3 KiB) Downloaded 338 times
Administrator
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Post by Administrator »

I have made a few changes.

First, I think you really wanted to delay the birth rate rather than the "0-1" level. By delaying the level, you were removing "0-1" from that level rather than the births as people age.

The model I have uploaded is what I think you are after. Run it in Synthesim mode and use the "switch" to change the drain on the "0-1" level. One drain uses "delay fixed", the other has the standard delay used in a lot of SD models (you used it to drain the "16-20" level).

Is this what you are after?

Hope it helps.

Tony.
Attachments
age_2.mdl
(4.43 KiB) Downloaded 340 times
viladent
Junior Member
Posts: 11
Joined: Sun Sep 18, 2005 2:53 pm

Post by viladent »

Hello Tony,

Unfortunately, I cannot open "age2" as it saves as mdl.php format which is not recognized on my PC, is it because I have an old version? or is it because I only have a PLE on my home PC? (I have PLE V5.a) In any case I will re-load "age2" tomorow on the university PC where we have the full version.
I undestand your comment about delaying the birth rate instead the level.
About your question the file "age" I attached with my mail yesterday is an extract of the more extensive model I am working on at the moment.
Best regards
Christian
Administrator
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Post by Administrator »

Try renaming the file to age2.mdl, it should work fine then.

For some reason, when downloading from the forum, files get their extensions mixed up.

Tony.
viladent
Junior Member
Posts: 11
Joined: Sun Sep 18, 2005 2:53 pm

Post by viladent »

I renamed your file and also cleaned previous mdl files (it seems that some interferences could occur between new and former file with close names), now everything works fine.
Thanks a lot again.
Chris
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