  The Einstein Telescope (ET) has been proposed as one of the third-generation
gravitational wave (GW) detectors. The sensitivity of ET would be a factor of
10 better than the second-generation GW detector, Advanced LIGO (aLIGO); thus,
the GW source parameters could be measured with much better accuracy. In this
work, we show how the precision in parameter estimation can be improved between
aLIGO and ET by comparing the measurement errors. We apply the TaylorF2
waveform model defined in the frequency domain to the Fisher matrix method
which is a semi-analytic approach for estimating GW parameter measurement
errors. We adopt as our sources low-mass binary black holes with the total
masses of $M\leq 16 M_{\odot} $ and the effective spins of $-0.9 \leq \chi_{\rm
eff} \leq 0.9$ and calculate the measurement errors of the mass and the spin
parameters using $10^4$ Monte-Carlo samples randomly distributed in our mass
and spin parameter space. We find that for the same sources ET can achieve
$\sim 14$ times better signal-to-noise ratio than aLIGO and the error ratios
($\sigma_{\lambda, \rm ET}/\sigma_{\lambda, \rm aLIGO}$) for the chirp-mass,
symmetric mass ratio, and effective spin parameters can be lower than $7\%$ for
all binaries. We also consider the equal-mass binary neutron stars with the
component masses of 1, 1.4, and 2 $M_{\odot}$ and find that the error ratios
for the mass and the spin parameters can be lower than $1.5 \%$. In particular,
the measurement error of the tidal deformability $\tilde{\Lambda}$ can also be
significantly reduced by ET, with the error ratio of $3.6 - 6.1 \%$.
