Specific case question

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Radboud
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Specific case question

Post by Radboud »

I'm unable to fix the beneath case
in addition to extend my stock-flow model, can somebody help me out?

The adaption rate of potential car owners is further investigated. For that,
replace the fixed rate of 30 million car buyers per year by the following ‘word of mouth’
phenomenon. Each car owner has an average of 100 contacts per year. On average 1.2 per 1000 of
these contacts lead to someone buying a car. The adoption rate can now be calculated by multiplying
the number of car owners with their contact rate and with the adoption fraction, and then be
multiplied by the fraction of the total population that consists of potential car owners.''
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Cars and c02.mdl
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Administrator
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Re: Specific case question

Post by Administrator »

This looks like a homework question, is that correct?
Advice to posters seeking help (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391

Units are important!
http://www.bbc.co.uk/news/magazine-27509559
Radboud
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Joined: Wed May 01, 2019 8:56 am
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Re: Specific case question

Post by Radboud »

It's a case indeed. Is this the right place to ask questions or is there another place to ask specific case-related questions?
Administrator
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Re: Specific case question

Post by Administrator »

This is the right place to ask for help, we will not do your homework for you though.

Best option is to try yourself and if you have any specific questions, then feel free to ask.
Advice to posters seeking help (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391

Units are important!
http://www.bbc.co.uk/news/magazine-27509559
Radboud
Junior Member
Posts: 3
Joined: Wed May 01, 2019 8:56 am
Vensim version: PLE

Re: Specific case question

Post by Radboud »

Thanks for your response, i think i did a good job so far. But now am stuck on the unit contacts..
Contacts has as input Car owners and contact rates .. any suggestion?
tomfid
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Re: Specific case question

Post by tomfid »

In the Bass diffusion model, typically there's a contact rate parameter which is in units of people contacted per person doing the contacting per unit time. The people cancel out, leaving 1/time, though it's often clearer to preserve them as people/person/time.
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