  The question is addressed to what extent incompressible magnetohydrodynamics
(MHD) can describe random magnetic and velocity fluctuations measured in the
solar wind. It is demonstrated that distributions of spectral indices for the
velocity, magnetic field, and total energy obtained from high resolution
numerical simulations are qualitatively and quantitatively similar to solar
wind observations at 1 AU. Both simulations and observations show that in the
inertial range the magnetic field spectrum E_b is steeper than the velocity
spectrum E_v with E_b >~ E_v and that the residual energy E_R = E_b-E_v
decreases nearly following a k_perp^-2 scaling.
