On Wed, Feb 28, 2024 at 8:50 AM Sven Schreiber
<sven.schreiber(a)fu-berlin.de> wrote:
Am 28.02.2024 um 09:37 schrieb Brian Revell:
There is an irritation in using the Forecast Function in Analysis in that it treats Panel
data as a continuum between adjacent panel units in plotting by observation number
sequence. So as illustrated below, there are 21 annual observations in Panel 1 ending in
2021. However the forecast funtion treats this as as a observation continuum from 1:21 to
2:01(year 2001) and plots an irritaing line between1:21 and 2:01......and similarly
between all the adjacent 10 Panel Units. Is there anyway to suppress this joining line, as
the forecast graph plots beautiful CI shaded areas.
The workaround is to transfer the data to Excel -but that does not provided a shaded 95%
CI -which is clearly more elegan -only the ability to plot the Upper and lower CI bounds
as lines..
Hi Brian,
I tried to run a forecast on the grunfeld example panel dataset shipped with gretl. I
restricted the sample to leave out the last two time periods, to save them for
forecasting, and then estimated a trivial dynamic/reduced-form fixed-effects regression
with "invest" as the dep. variable. (Let's ignore the Nickell bias issues
for this example.) No contemporaneous variables, but in the model window under the
Analysis menu the "Forecasts..." entry was still greyed out, so I couldn't
cross-check what you described.
So, it would be helpful if you could describe how exactly and with what data you produced
your forecasts.
There's a sort of "loophole" here in that you're offered the Forecast
option under the Analysis menu if you estimate via pooled OLS on panel
data -- and in that case you get what Brian's describing. It seems we
weren't really ready to offer GUI forecasts for panel data, but the
OLS case slipped through.
Allin