  We examine the thermodynamic properties of the hole- and electron-doped
cuprates by using the t-t'-t''-J model. We find that the chemical potential
shows different doping dependence between the hole and electron dopings. Recent
experimental data of the chemical potential shift are reproduced except for
lightly underdoped region in the hole doping where stripe and/or charge
inhomogeneity are expected to be important. The entropy is also calculated as a
function of the carrier concentration. It is found that the entropy of the
electron-doped system is smaller than that of the hole-doped systems. This is
related to strong antiferromagnetic short-range correlation that survives in
the electron-doped system.
