Description Usage Arguments Details Value Author(s) References See Also Examples
EPS-based chronology stripping after Fowler & Boswijk 2003.
1 2 |
rwl |
a |
ids |
an optional |
verbose |
|
comp.plot |
|
legacy.eps |
|
The EPS-based chronology stripping is implemented after
Fowler & Boswijk 2003: First, all series are standardized using a
double detrending procedure with splines and frequency cutoffs of 50%
at 20 and 200 years. Then, EPS is calculated for the
chronology including all (remaining) series. In each iteration, the
algorithm calculates leave-one-out EPS values, and the
series whose removal increases overall EPS the most is
discarded. This is repeated until no further increase in
EPS is gained by discarding a single series. The procedure
is then repeated in the opposite direction, i.e., the reinsertion of
each previously removed series into the data.frame
is
considered. In each iteration, the series (if any) whose reinsertion
increases EPS the most is reinserted. As a last step,
EPS is calculated for each year of the stripped and original
chronology including all series. If comp.plot
is set to
TRUE
, a diagnostic plot is shown for the year-wise comparison.
When verbose output is chosen, the EPS values for all leave-one-out (or back-in) chronologies are reported. If discarding or re-inserting a single series leads to an improvement in EPS, this series is marked with an asterisk.
The functions returns a data.frame
of raw tree-ring widths,
where series that do not contribute to an overall improvement in
EPS are left out.
Christian Zang. Patched and improved by Mikko Korpela.
Fowler, A. and Boswijk, G. (2003) Chronology stripping as a tool for enhancing the statistical quality of tree-ring chronologies. Tree-Ring Research, 59(2), 53–62.
1 2 3 4 5 |
REMOVE -- Iteration 1: Initial EPS: 0.931
Leave-one-out EPS:
ANOS111K: 0.929
ANOS101G: 0.93
ANOS101K: 0.925
ANOS102G: 0.931
ANOS102K: 0.926
ANOS105G: 0.923
ANOS105O: 0.922
ANOS106G: 0.922
ANOS106K: 0.926
ANOS107G: 0.926
ANOS107K: 0.928
ANOS108G: 0.927
ANOS108K: 0.926
ANOS111G: 0.923
ANOS114K: 0.928
ANOS110G: 0.927
ANOS110K: 0.926
ANOS112G: 0.931
ANOS112K: 0.928
ANOS114G: 0.926
***
REMOVE -- Iteration 1: no improvement of EPS. Aborting...
Warning message:
executing %dopar% sequentially: no parallel backend registered
ANOS111K ANOS101G ANOS101K ANOS102G ANOS102K ANOS105G ANOS105O ANOS106G
2002 2.71 2.51 0.88 1.11 1.85 1.69 2.71 1.17
2003 1.55 1.39 0.58 0.91 1.22 0.88 1.16 0.54
2004 1.86 1.54 0.47 0.45 1.16 0.25 0.62 0.36
2005 2.26 1.60 0.50 0.66 1.28 0.45 0.83 0.42
2006 2.45 1.73 0.56 0.38 1.43 0.85 1.18 0.52
2007 3.79 2.47 1.18 0.74 1.45 1.24 1.79 0.82
ANOS106K ANOS107G ANOS107K ANOS108G ANOS108K ANOS111G ANOS114K ANOS110G
2002 1.74 2.25 1.21 0.89 1.76 2.36 2.56 0.53
2003 0.75 1.27 1.01 0.75 0.82 1.32 0.81 0.39
2004 0.46 0.83 0.57 0.18 0.16 0.91 0.33 0.29
2005 0.53 0.98 0.59 0.25 0.33 1.08 1.11 0.11
2006 0.72 1.18 0.74 0.37 0.26 1.00 0.98 0.32
2007 1.32 2.62 1.00 0.42 0.86 3.07 1.27 0.76
ANOS110K ANOS112G ANOS112K ANOS114G
2002 1.22 1.73 2.21 2.29
2003 0.80 0.85 1.57 0.72
2004 0.11 0.50 0.68 0.42
2005 0.27 0.84 0.85 1.06
2006 0.46 1.12 1.14 1.19
2007 1.29 1.61 2.12 1.35
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