  We introduce the heterogeneous voter model (HVM), in which each agent has its
own intrinsic rate to change state, reflective of the heterogeneity of real
people, and the partisan voter model (PVM), in which each agent has an innate
and fixed preference for one of two possible opinion states. For the HVM, the
time until consensus is reached is much longer than in the classic voter model.
For the PVM in the mean-field limit, a population evolves to a "selfish" state,
where each agent tends to be aligned with its internal preference. For finite
populations, discrete fluctuations ultimately lead to consensus being reached
in a time that scales exponentially with population size.
