This is a fairly direct implementation of the multiplier-accelerator model from Paul Samuelson’s classic 1939 paper,
“Interactions between the Multiplier Analysis and the Principle of Acceleration” PA Samuelson – The Review of Economics and Statistics, 1939 (paywalled on JSTOR, but if you register you can read a limited number of publications for free)
This is a nice example of very early economic dynamics analyses, and also demonstrates implementation of discrete time notation in Vensim.
See also:
The multiplier-accelerator model of business cycles interpreted from a system dynamics perspective. GW Low – Elements of the System Dynamics Method, 1980 – MIT Press: Cambridge, MA
I’d love to have a copy of the Low model as a companion, if anyone is inclined to replicate it.
See my blog post for more description of the model.
Download for any version of Vensim:
The influence diagram shows that C(t)—–>C(t-1).
That may be wrong!
Cheers
Tom
Maybe weird, but not wrong, except to the extent that the whole model is wrong. What it implies is that the past value of C depends on (is a delay of) the present value of C.