  The magnitude of long-range correlations between observables in two separated
rapidity windows, proposed as a signature of the string fusion and percolation
phenomenon, is studied in the framework of non-Glauber Monte Carlo
string-parton model, based on the picture of elementary collisions of color
dipoles. The predictions, obtained with and without string fusion, demonstrate
effects of color string fusion on the observables in Pb-Pb collisions at the
LHC: decrease of n-n correlation coefficient with centrality and negative pt-n
correlations, if the sufficiently effective centrality estimator is applied. In
general case it is shown that the values of n-n and pt-n correlation
coefficients strongly depend on the method of collision centrality fixation. In
contrast, the predictions obtained for pt-pt correlation have almost no effect
of centrality determination method and the corresponding experimental data
would produce the strong limitation on the transverse radius of a string.
