The World Health Organization (WHO) reports that malaria, a parasitic disease transmitted by mosquitoes, causes over 300 million episodes of "acute illness" and more than one million deaths annually. Most of the deaths occur in poor countries of the tropics, and especially sub-Saharan Africa....

The ratio of Indian to US per capita output over the past 45 years has displayed a distinctive "V"-shaped pattern. We show that a strikingly similar V-shaped pattern is visible not just in aggregate output .figures, but also as the primary determinant of long-term movements in the...