Model-independent Representation of Electroweak Data
  General model-independent expressions are developed for the polarized and unpolarized cross-sections for $e^+e^-\to f\bar f$ near the $Z^0$ resonance. The expressions assume only the analyticity of S-matrix elements. Angular dependence is included by means of a partial wave expansion. The resulting simple forms are suitable for use in fitting data or in Monte Carlo event generators. A distinction is made between model-independent and model-dependent QED corrections and a simple closed expression is given for the effect of initial-final state bremsstrahlung and virtual QED corrections. 
Robin G. Stuart (Randall Laboratory of Physics)