Stellar Synthesis Population Models:
Obtain spectra of all spectral types over wide range of wavelengths (use models to fill
gaps).
Combine spectra according to an initial mass function.
Age the starburst by removing spectra of the most massive stars first, according to their
lifetimes, etc.
Add together combinations of starbursts (e.g., different instantaneous bursts, or according to
some prescription like constant star formation or exponentially decaying star formation.
A couple of homework problems explore this topic.