lookup help

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Jay
Newbie
Posts: 1
Joined: Fri Mar 29, 2002 3:39 am

lookup help

Post by Jay »

I downloaded PLE several days ago and put together the attached model for learning purposes.

I have tried multiple approaches to combine the effects of changing Membership and the AttendanceEffectFunction lookup to plot how they might affect Giving. As shown in the attachment, the lookup table has no effect. All attempts were unsuccessful so there is obviously something I am missing about lookups. (I did get an identical iThink model to work successfully). The approaches were attempting to emulate 'Named Lookups' on page 119 of the pdf manual.

If anyone can find a few minutes to fix the attached model or otherwise help out, it would get me moving again and be much appreciated. Any comparative thoughts about iThink would also be appreciated.

Thank you

Jay
design@rcn.com
Attachments
jayTest.mdl
(3.75 KiB) Downloaded 333 times
LAUJJL
Senior Member
Posts: 1427
Joined: Fri May 23, 2003 10:09 am
Vensim version: DSS

lookup

Post by LAUJJL »

Hi Jay

A good idea first is to have a model without unit errror or warning messages.

Your lookup does not have any effect, because it cannot have any, the ratio being never above 2 and the lookup starting its effect above about 6.
Joined a model with different values for the lookup that has an effect.
Regards.
JJ
Attachments
jayTest_2.mdl
(3.76 KiB) Downloaded 361 times
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