  Results of Monte Carlo simulations of the one-dimensional long-range Ising
spin glass with power-law interactions in the presence of a (random) field are
presented. By tuning the exponent of the power-law interactions, we are able to
scan the full range of possible behaviors from the infinite-range
(Sherrington-Kirkpatrick) model to the short-range model. A finite-size scaling
analysis of the correlation length indicates that the Almeida-Thouless line
does not occur in the region with non-mean-field critical behavior in zero
field. However, there is evidence that an Almeida-Thouless line does occur in
the mean-field region.
