  The ratio of symmetry energy coefficient to temperature $C_{sym}/T$ is
extracted from different prescriptions using the isotopic as well as the
isobaric yield distributions obtained in different projectile fragmentation
reactions. It is found that the values extracted from our theoretical
calculation agree with those extracted from the experimental data but they
differ very much from the input value of the symmetry energy used. The best
possible way to deduce the value of the symmetry energy coefficient is to use
the fragment yield at the breakup stage of the reaction and it is better to use
the grand canonical model for the fragmentation analysis. This is because the
formulas that are used for the deduction of the symmetry energy coefficient are
all derived in the framework of the grand canonical ensemble which is valid
only at the break-up (equilibrium) condition. The yield of "cold" fragments
either from the theoretical models or from experiments when used for extraction
of the symmetry energy coefficient using these prescriptions might lead to the
wrong conclusion.
