Hi
I have got an issue, I estimated a model, I used Prais-Winsten
autoregressive model (lag one and constant), I forecasted the value for the
next two years, see table below:
For 95% confidence intervals, t(4, 0.025) = 2.776
Obs Global_Sales prediction std. error 95% interval
2004 125.00 125.47
2005 139.00 139.01
2006 151.00 150.70
2007 166.82 0.693 164.89 -
168.74
2008 181.81 0.709 179.84 -
183.77
My question is; how the std. error is calculated, I could calculate the std.
error for 2007 (summarize of the squares of residuals, divided by n-2), but
I do not know how it is calculated for the next year (2008 - 0.709)
Does anybody know the formula or how it is calculated? I am interested in
any paper or book where I can find it.
Thank you very much
Kind regards
Francisco Sosa
dd: +44 (0) 20 7448 3875
email: francisco(a)digitab.uk.com
digitab
tel: +44 (0) 20 7588 6669
fax: +44 (0) 20 7256 7540
digitab 4th floor 6-8 bonhill street london ec2a 4bx
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Hi I have got an issue, I estimated a model, I used Prais-Winsten
autoregressive model (lag one and constant), I forecasted the value for the
next two years, see table below: For 95% confidence intervals, t(4, 0.025) = 2.776 Obs Global_Sales
prediction std.
error 95% interval
2004
125.00 125.47
2005
139.00 139.01
2006
151.00 150.70 2007
166.82 0.693
164.89 - 168.74
2008
181.81 0.709
179.84 - 183.77 My question is; how the std. error is calculated, I could
calculate the std. error for 2007 (summarize of the squares of residuals,
divided by n-2), but I do not know how it is calculated for the next year (2008
– 0.709) Does anybody know the formula or how it is calculated? I am
interested in any paper or book where I can find it. Thank you very much Kind regards
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