تلفات زلزله : تعامل ماهیت و اقتصاد سیاسی

To say that the level of fatalities resulting from an earthquake is inversely related to a country's per capita level of income is hardly novel. What makes our approach novel is that we relate fatalities to both per capita income and the level of inequality that exists within a country through their joint impact on the likelihood of collective action being taken to mitigate the destructive potential of quakes. We first develop a theoretical model which offers an explanation as to why, in some environments, different segments of society prove incapable of arriving at what all parties perceive to be an agreeable distribution of the burden of the necessary collective action, causing the relatively wealthy simply to self-insure against the disaster while leaving the relatively poor to its mercy. Following this, we test our theoretical model by evaluating 269 large earthquakes occurring worldwide, between 1960 and 2002, taking into account other factors that influence a quake's destructiveness such as its magnitude, depth and proximity to population centers. Using a Negative Binomial estimation strategy with both random and fixed estimators, we find strong evidence of the theoretical model's predictions. That is, while earthquakes themselves are natural phenomena beyond the reach of humankind, our collective inaction with respect to items like the creation and enforcement of building codes, failure to retrofit structures and to enact quake-sensitive zoning clearly plays a part in determining the actual toll that a given quake takes. And, it is through these and other examples of collective inaction that limited per capita income and inequality couple together with a given quake's natural destructive power in determining the actual fatalities resulting from a quake.

Until recently, a country's level of inequality has been viewed as an outcome of its general economic performance, rather than an input into that performance. This began to change in the 1990s with the publication of a number of papers that addressed the impact that inequality itself might have on a country's economic performance, especially on its growth rate. Galor and Zeira (1993), Bertola (1993), Alesina and Rodrik (1994), Persson and Tabellini (1994), and Benabou (1996) have been among the frontrunners of this literature. The initial impulses in this strand of research concerned the political economy implications of inequality (especially tax selection by the median voter) and capital market imperfections (which limit the investment options for the relatively poor) as the main channels through which inequality might impact the overall efficiency and growth of an economy. Another strand of related research extends these outcomes by suggesting that inequality can be linked to economic performance in other ways. Examples include the role that inequality can play in political instability, as evidenced by greater social conflict, which can lead to reduced investment levels (Alesina and Perotti, 1996) and limit a country's ability to effectively respond to external shocks (Rodrik, 1999). Further, such social conflict inevitably leads to increased violence and crime, which also can reduce the overall economic performance of a country through its direct costs in lives and property damaged and through its indirect costs in terms of medical resources required to treat those injured, lost productivity from those injured or killed and the resources needed for policing that must be diverted from other, arguably more productive, activities to mitigate, if not prevent, these criminal activities (see Fajnzylber et al., 2002 and Bourguignon, 2001).

Earthquakes and other natural disasters claim tens of thousands of lives worldwide each year, not to mention the accompanying billions of dollars in property damage. Too often there is a tendency to ascribe such events to uncontrollable “acts of nature,” releasing humankind of any role in the tragedies. In this paper, we develop and test a theoretical model that suggests that, in fact, political–economic institutions are at least partly responsible for earthquake fatalities. That is, we develop a theoretical model which shows that collective action in the form of creation and enforcement of building codes, appropriate professional licensing, earthquake-sensitive zoning and, if needed, retrofitting of structures can significantly reduce the devastation of major earthquakes. More importantly, this model shows that the probability of collective action is an increasing function of a country's per capita level of income and degree of equality. We test these predictions by considering, in a Random/Fixed Effects Negative Binomial framework, 269 major earthquakes occurring worldwide between 1960 and 2002. The results strongly support the predictions of the theoretical model. Thus, policies designed to improve per capita income and reduce inequality can be expected to, through their impact on the likelihood of collective action, mitigate the effects of major quakes. Of course, such policies are easier recommended than developed and implemented. And, unfortunately, improvements in these areas, in and of themselves, cannot be expected to fully alleviate the devastation done by severe quakes. Yet, it is our hope that this analysis provides yet one more reason to work toward policies that serve to increase per capita income and equality, especially in the developing world, where natural disasters such as earthquakes impose their greatest costs.