Researchers at Yale University and the University of Connecticut found that the single most important factor driving whether a given homeowner installed solar panels was peer influence. Examining the spread of solar panels on residences in Connecticut, the researchers found that the installation of one additional PV project within the past six months in a given area increased the average number of installations within a half mile radius by .44, or almost one half. As the spatial area widened, the influence of peer installations steadily decreased. Within a mile radius, the installation of one solar panel in the prior 6 months increased installations by .39, and within a 1 to 4 mile radius, by .12. This peer influence factor is consistent with past research done in California.