Giving time series data

[sankee82]

I have given time series data as input to my variables. The data is annual in nature. I have set the time step to year in initial settings of the model. However when I am trying to plot the variable it is observed that the values are plotted with an interval of one month. How to rectify it?

[tomfid]

You probably just need to change the unit for Time in Model>Settings>Time Bounds.

After you've done that, you should define and check all your other units.

[sankee82]

You probably just need to change the unit for Time in Model>Settings>Time Bounds.

After you've done that, you should define and check all your other units.

I have already done it. Still the data is taken at a step of one month.

[tomfid]

Can you post the model & data, or a screenshot of a sample of each?

[sankee82]

Can you post the model & data, or a screenshot of a sample of each?

I am attaching model, excel data and graph of one of the variable.

[tomfid]

The Year column in your spreadsheet is not numeric, it's text. I'm not sure what Vensim is assuming about the time axis, because you haven't provided the equations or imported .vdf, but I'm guessing that if you fix the timing it will work.

[sankee82]

I am unable to understand how to use the imported data in writing equations involving time series. Can you please help me with it. I know this is very small thing to ask for, but as I am new to Vensim it is talking me a lot of time to figure out.

[tomfid]

This might be a good place to start: http://vensim.com/documentation/usr16.htm

[JudeChen]

Hi,

If my Units for Time is set at Yearly, and my Time Step is at 0.0625, does Vensim read XLS data for time in the monthly or yearly manner here?

I am currently using the VensimDSS (S/N 9510), academic use license although it says VensimPLE on my profile.

[tomfid]

Vensim will be looking for time formatted as a decimal year.

[JudeChen]

Vensim will be looking for time formatted as a decimal year.

Okay. thanks! So should i input the info as based on monthly or yearly data?

[Administrator]

If your model runs in years, then input it as yearly data if you can as otherwise things can get confusing.

[tomfid]

Are you talking about the units or granularity of the data? Generally it's always better to use the finest time scale you can, given the time step of the model.