Download Instructions

Download PEST 11.8 which includes executables, the PEST Manual and the PEST Manual Addendum in PDF format.

Unzip the contents to a directory cited in the PATH environment variable. (This is very important as, when undertaking SVD-assisted parameter estimation, PEST runs the parcalc.exe and picalc.exe utility programs. It is essential that the operating system knows where to find these).

Make sure that the directory holding older versions of PEST (including version 9) are no longer in the PATH string, as old versions of parcalc.exe and picalc.exe are not compatible with the new PEST.

Download the PEST manual

Download the addendum to the PEST manual

PEST Version 11.8 for the PC (November 2008)

New features in PEST version 11.8 include the following:

·         Improved regularization functionality – including “null-space enhanced” Tikhonov regularization which is unique to PEST. This provides another safeguard against numerical instability when undertaking highly parameterized inversion.

·         Linear predictive uncertainty analysis is now much easier with the GENLINPRED utility. This allows a user to calculate the following quantities (and more):

o        parameter identifiability;

o        parameter contributions to predictive uncertainty and predictive error variance;

o        the comparative worth of different existing or yet-to-be gathered data in terms of its ability to reduce predictive uncertainty.

·         Calculation of “super observations”. These are orthogonal linear functions of the data that are uniquely informative of orthogonal linear functions of the model parameterization.