Palgrave Handbook of Econometrics: Applied Econometrics

D.S.G. Pollock 301

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11

12

13

1875 1900 1925 1950 1975 2000

Figure 6.21 The annual series of the logarithms of real GDP in the UK, at constant prices,
for the years 1873–2001. A polynomial of degree 4 has been fitted to the data by least squares
regression

0.00

0.05

0.10

0.15

–0.05

–0.10

–0.15

1875 1900 1925 1950 1975 2000

Figure 6.22 The residual obtained from fitting a polynomial of degree 4 to the logarithmic
GDP data of Figure 6.21

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1875 1900 1925 1950 1975 2000

Figure 6.23 The logarithms of annual UK real GDP from 1873 to 2001 with an interpolated
trend. The trend is estimated via a filter with a variable smoothing parameter