  We explain the findings by Di Leonardo et al. [Phys. Rev. Lett. 84, 6054
(2000)] that the effective temperature of a Lennard-Jones glass depends only on
the final value of the density in the volume and/or temperature jump that
produces the glass phase. This is not only a property of the Lennard-Jones
liquid, but a feature of all strongly correlating liquids. For such liquids
data from a single quench simulation provides enough information to predict the
effective temperature of any glass produced by jumping from an equilibrium
state. This prediction is validated by simulations of the Kob-Andersen binary
Lennard-Jones liquid and shown not to apply for the non-strongly correlating
monatomic Lennard-Jones Gaussian liquid.
