Search found 5 matches

by sl590
Tue Jun 05, 2018 5:26 pm
Forum: Vensim
Topic: Help: time series data with time lags
Replies: 7
Views: 4245

Re: Help: time series data with time lags

tomfid wrote: Tue Jun 05, 2018 12:35 pm This explains the mapping between discrete and continuous time, and why discrete notation for continuous phenomena is usually problematic:
http://metasd.com/2017/11/discrete-time-stinks/
Thank you, will have a look
by sl590
Mon Jun 04, 2018 7:42 pm
Forum: Vensim
Topic: Help: time series data with time lags
Replies: 7
Views: 4245

Re: Help: time series data with time lags

I think it's probably best if you have a go first and upload the model if you have any problem. Things like k_k(t-1) is not the right way to think about it when building a model. Vensim steps forwards in "time step" increments, so t-1 can mean today - 1 (yesterday), this month - 1 (yester...
by sl590
Mon Jun 04, 2018 6:57 pm
Forum: Vensim
Topic: Help: time series data with time lags
Replies: 7
Views: 4245

Re: Help: time series data with time lags

This question is far too vague to really provide an answer. What do these equations even mean? Hi, thank you for the reply. I only took a few equations out of the system, as I don't know how to include lagged variables in a vensim model. However, to explain what the equations are: 1. capital stock ...
by sl590
Mon Jun 04, 2018 6:51 pm
Forum: Vensim
Topic: Help: time series data with time lags
Replies: 7
Views: 4245

Re: Help: time series data with time lags

Hi there, thank you for the reply. I only took a few equations out of the system, as I don't know how to include lagged variables in a vensim model. However, to explain what the equations are: 1. capital stock grows at a rate of gr_k, hence at time t, k_k(t)= k_k(t-1)*(1+gr_k) 2. the growth rate is ...
by sl590
Mon Jun 04, 2018 5:43 pm
Forum: Vensim
Topic: Help: time series data with time lags
Replies: 7
Views: 4245

Help: time series data with time lags

Hi all, I was working on eviews on a macroeconomic model. The model is a system of simultaneous equations, which I think Vensim will be great to work on the simulations. However, the model has the following properties for many variables: 1. k_k(t) = k_k(t-1)*(1 + gr_k(t)) 2. gr_k(t) = gamma0 + gamma...