To test the utility of the modified Kim-Anderson model for study of the magnetic response of ceramic superconductors, we measured ac complex susceptibilities x
n=x'
n-ix"
n(n=1, 2, 3, 5, 7) of a single-crystal thin film Bi
2Sr
2CaCu
2O
y, and attempted to simulate the results in the framework of this model. Analyses of x
n, have shown that generation of the higher-harmonics can be reproduced pretty well, where the material parameters k and B
0, the surface barrier ΔH and the lower critical field H
CI involved were used as the fitting parameters. From the even-n harmonic susceptibility x
2 which reflects the asymmetric nature of the magnetization curve, we foundthat the critical-current density J
c of the Bi
2Sr
2CaCu
2O
y film depends sensitively on the local flux density B
i. This result is a provoking contrast to the B
i, dependence of J
c. for an YBa
2Cu
3O
y film.
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