Implications of CTEQ PDF analysis for collider observables

In the context of a recent CTEQ6.6 global analysis, we review a new technique for studying correlated theoretical uncertainties in hadronic observables associated with imperfect knowledge of parton distribution functions (PDFs). The technique is based on the computation of correlations between the predicted values of physical observables in the Hessian matrix method. It can be used, for example, to link the dominant PDF uncertainty in a hadronic cross section to PDFs for individual parton flavors at well-defined $(x,\mu)$ values. As an illustration, we apply the PDF correlation analysis to study regularities in the PDF dependence of Z, W, and Higgs boson production cross sections at the Tevatron and LHC.