Journal of Paleolimnology

, Volume 25, Issue 1, pp 111–115

Maximum likelihood environmental calibration and the compute program WACALIB a correction

  • H.J.B. Birks


A recently discovered error in the part of the computer program WACALIB that implements maximum likelihood (ML) calibration has been discovered and corrected. The new version of WACALIB has been re-run with all the data-sets from which results based on the earlier version of WACALIB had been published. The new results suggest that ML regression and calibration perform as well or even better than weighted averaging (WA), at least when judged by the apparent root mean squared error. Further work involving cross-validation is required to evaluate more fully the relative performance of WA and ML approaches.

maximum likelihood Gaussian regression weighted averaging computing environmental reconstruction 


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Copyright information

© Kluwer Academic Publishers 2001

Authors and Affiliations

  • H.J.B. Birks
    • 1
    • 2
  1. 1.Botanical InstituteUniversity of BergenBergenNorway
  2. 2.Environmental Change Research CentreUniversity College LondonLondonUK

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