  The study of extragalactic integrated light can yield partial information on
stellar population ages, abundances, and the initial mass function (IMF). The
power-law slope of the IMF has been studied in recent investigations with
gravity-sensitive spectral indicators that hopefully measure the ratio between
KM dwarfs and giants. We explore two additional effects that might mimic the
effects of the IMF slope in integrated light, the low mass cutoff (LMCO) and a
variable contribution of light from the asymptotic giant branch (AGB). We show
that the spectral effects of these three (IMF slope, LMCO, AGB strength) are
subtle compared to age-abundance effects. We illustrate parameter degeneracies
and covariances and conclude that the three effects can be disentangled, but
only in the regime of very accurate observations, with enhanced effectiveness
if high-precision photometry is combined with spectroscopy.
