  As the rental housing market moves online, the Internet offers divergent
possible futures: either the promise of more-equal access to information for
previously marginalized homeseekers, or a reproduction of longstanding
information inequalities. Biases in online listings' representativeness could
impact different communities' access to housing search information, reinforcing
traditional information segregation patterns through a digital divide. They
could also circumscribe housing practitioners' and researchers' ability to draw
broad market insights from listings to understand rental supply and
affordability. This study examines millions of Craigslist rental listings
across the US and finds that they spatially concentrate and over-represent
whiter, wealthier, and better-educated communities. Other significant
demographic differences exist in age, language, college enrollment, rent,
poverty rate, and household size. Most cities' online housing markets are
digitally segregated by race and class, and we discuss various implications for
residential mobility, community legibility, gentrification, housing voucher
utilization, and automated monitoring and analytics in the smart cities
paradigm. While Craigslist contains valuable crowdsourced data to better
understand affordability and available rental supply in real-time, it does not
evenly represent all market segments. The Internet promises information
democratization, and online listings can reduce housing search costs and
increase choice sets. However, technology access/preferences and information
channel segregation can concentrate such information-broadcasting benefits in
already-advantaged communities, reproducing traditional inequalities and
reinforcing residential sorting and segregation dynamics. Technology platforms
like Craigslist construct new institutions with the power to shape spatial
economies.
