The effect of the general vector, axialvector, scalar and tenser inter
actions on the theoretical description of neutron decay is investigate
d. Results of least squares adjustment computations for the weak coupl
ing constants are presented (neutron decay and several nuclear beta de
cay observables have been employed), A simple calculation method, whic
h makes it possible to get analytical formulae for many important dist
ributions and quantities of neutron decay, is described, The sensitivi
ties of the electron and proton spectra and asymmetries and of two com
bined electron-proton asymmetries to the determination of the most imp
ortant phenomenological parameters are studied by statistical methods.