How applicable are scaling laws in predicting slum populations in urban systems? Evidence from India

Recently, we have seen new developments in our understanding of the emergence and organization of cities and urban systems, including application of scaling laws to urban areas. A recent wave of studies has observed consistent behavior of multiple urban measures that scale with city size across geographic and sectoral contexts. However, the extant evidence is lacking in two important ways: first, a wide variety of urban measures still remain unexplored, and second, there is limited evidence from developing countries. This paper offers new evidence on both these fronts: i) applying scaling laws to predict slum population in cities, an urban measure that remains largely unexplored, and ii) applying them in the context of a developing country, India. Results suggest that population alone is not sufficient to predict slum population in India. Conversely, I use empirical results from scaling laws to test established slum growth theories that have influenced policymaking globally for decades, despite having limited empirical evidence to support them. I also show that scaling exponents are sensitive to the way we define urban systems, of which cities are a part, an issue that has been raised in the ongoing methodological debate on urban scaling laws. I believe that findings presented in this paper have implications for advancement of slum theories as well as urban scaling laws by offering new empirical evidence and mechanisms through which such scaling might happen in the context of slums.