How to split a stock variable?
Posted: Sun Mar 14, 2010 10:10 am
Hi,
due to my lack of knowledge I run into a problem. Maybe someone could give my an advise.
I have a stock variable A. There is one input (a constant!) and there are two outputs. The outputs depend on the value of A.
A holds the amount the people from age 0 to age 9 (example). The input is a constant birth rate (100 per year), the first output is 1/10 ... so every year 1/10 of the people leave the stock and move to a second stock. The second output is k*A where k is some factor (people moveing to another location). So far, so good.
Now I would like to split the stock variable A into to new stocks (named C and D). The reason: the modelling of ages range from 0 to 9 is too big. I want an age range from 0 to 3 and from 4 to 9.
The input to C is the same as to A (constant birth rate).
The first output from C to D is 1/4 (every year a quarter leaves this stock and moves the the next stock).
The output from D is 1/6 (a sixth leaves the stock every year)
But how to calculate the second output from C (say k1*C) and the second output from D (say k2*D)?
A reasonable assumption is, that k1 = 2*k2 - so actually I only need to find k1 or k2.
All in all the first system (only A) should behave like the second system (C and D) if I only regard the input / output.
Any help is appreciated!
Thanks,
jmu
due to my lack of knowledge I run into a problem. Maybe someone could give my an advise.
I have a stock variable A. There is one input (a constant!) and there are two outputs. The outputs depend on the value of A.
A holds the amount the people from age 0 to age 9 (example). The input is a constant birth rate (100 per year), the first output is 1/10 ... so every year 1/10 of the people leave the stock and move to a second stock. The second output is k*A where k is some factor (people moveing to another location). So far, so good.
Now I would like to split the stock variable A into to new stocks (named C and D). The reason: the modelling of ages range from 0 to 9 is too big. I want an age range from 0 to 3 and from 4 to 9.
The input to C is the same as to A (constant birth rate).
The first output from C to D is 1/4 (every year a quarter leaves this stock and moves the the next stock).
The output from D is 1/6 (a sixth leaves the stock every year)
But how to calculate the second output from C (say k1*C) and the second output from D (say k2*D)?
A reasonable assumption is, that k1 = 2*k2 - so actually I only need to find k1 or k2.
All in all the first system (only A) should behave like the second system (C and D) if I only regard the input / output.
Any help is appreciated!
Thanks,
jmu