Informal housing in the XXI century. Characteristics of the informal land and housing supply in Bogota during the first decade of the XXI century

This article characterizes the conditions of the informal land and housing supply during the first decade of the xxi century in Bogota, regarding magnitude and location of the informal urban growth (new occupations in the periphery and informal densification of consolidated areas), housing  conditions in recent occupations and the characteristics of the land market. The situation of the  last decade has been reconstructed based in aerial photography analysis, census data quantification  and data analysis from planning and control public entities. Results suggest that due to the relative  land scarcity in Bogotá, among other aspects, the informal market dynamics have experimented changes compared to previous decades, because the growth in consolidated urban areas becomes  more important than the informal urbanization of the peripheries, but at the same time informality  transcends the municipal perimeter to the neighboring municipalities.

Telecommunications and economic growth: an empirical analysis of sub-saharan Africa

We examine the effect on economic growth of mobile cellular phones in sub-Saharan Africa where a marked asymmetry is present between land-line penetration and mobile telecommunications expansion. This study extends previous ones along two important dimensions. First, we allow for the potential endogeneity between economic growth and telecommunications expansion by employing a special linear generalized method of moments (GMM) estimator. Second, we explicitly model for varying degrees of substitutability between mobile cellular and land-line telephony, so that greater expansion of mobile telecommunications can have a different impact whenever the level of land-line penetration differs. We find that mobile cellular phone expansion is an important determinant of the rate of economic growth in Sub-Saharan Africa. Moreover, we find that the contribution of mobile cellular phones to economic growth has been growing in importance in the region, and that the marginal impact of mobile telecommunication services is even greater wherever land-line phones are rare. Given the low cost of mobile telecommunications technology relative to other broad infrastructure projects, especially land-line infrastructure, we advocate that mobile telecommunication services be encouraged in the area.

Informality in the City: a Theoretical Analysis

This thesis theoretically studies the relationship between the informal sector (both in the labor and the housing market) and the city structure.