blue is hosted by Hepforge, IPPP Durham

BLUE = Best Linear Unbiased Estimate

This is the homepage of my BLUE project. It contains the up-to-date information about this ROOT implementation of the BLUE combination. Please refer to the latest manual for details on the implementation.

This software is freely distributed under the GNU Lesser General Public License. It has been written with care, still mistakes are not excluded and it comes without warranty. A number of example functions are provided that reproduce published combination results, and at the same time demonstrate the software usage.

Please inform me should you find mistakes or pecularities. Please give reference to Refs. [1, 2] should you base public results on this software. Should you have any question or suggestion please do not hesitate to send me a message.

Updates are planned on an irregular basis. If you want to be promptly infomed about this via e-mail, please send me a message.


  • 08-Jan-2015: Release of Version 2.1.0
  • 16-Sep-2014: Release of Version 2.0.0
  • 20-May-2014: Release of Version 1.9.2
  • 30-Apr-2014: Release of Version 1.9.1
  • 28-Jan-2014: Release of Version 1.9.0
  • 20-Dec-2013: Release of Version 1.8.0
  • 06-Dec-2013: Release of Version 1.7.0
  • 28-Nov-2013: Release of Version 1.6.0


  • [1] R. Nisius, BLUE: a software package to combine correlated estimates of physics observables within ROOT using the Best Linear Unbiased Estimate method - Program manual, Version x.y.z,
  • [2] R. Nisius, On the combination of correlated estimates of a physics observable, Eur.Phys.J. C74 (2014) 3004.

Last Change: 08-Jan-2015 by Richard Nisius.