  The cost/benefit analysis originally developed for infrastructures in the
economic sector has recently been extended by Florio et al to infrastructures
of basic research. As a case study the large accelerator LHC at CERN and its
experiments have been selected since as a paradigmatic example of frontier
research they offer an excellent case to test the CBA model. It will be shown
that in spite of this improved method the LHC poses serious difficulties for
such an analysis. Some principle difficulties are due to the special character
of scientific projects. Their main result is the production of new basic
scientific knowledge whose net social value cannot be easily expressed in
monetary terms. Other problems are related to the very strong integration of
LHC into the general activities of CERN providing however, interesting
observations concerning a new management style for global projects. Finally the
mission of CERN (including LHC) is unique since it was founded with two tasks -
promote science and bring nations together. No way has yet been developed to
assess in economic terms success for the second objective. The main conclusion
is that the overall result of the CB analysis, the Net Present Value, although
positive for LHC, has a large uncertainty and if used to assess a project needs
a detailed discussion. On the other hand partial results can be very useful,
for example for the results of education or technology transfer.
