The correlation function of a one-dimensional interface over a random
substrate, bound to the substrate by a pressure term, is studied by Monte-Carlo
simulation. It is found that the height correlation , averaged
over the substrate disorder, fits a form exp(-(j/b)^c) to a surprising
precision in the full range of j where the correlation is non-negligible. The
exponent c increases from 1.0 to 1.5 when the interface tension is taken larger
and larger.Comment: 7 pages, 5 figure