A contingent valuation survey (willingness-to-pay study) was conducted in 2004 to measure household demand for typhoid vaccines in a rural township in China with approximately 54,000 people living in 141 villages. The results showed that travel distance to vaccination sites and vaccination price...

This essay assesses the evolution of the way in which spatial data analytical methods have been incorporated into software tools over the past two decades. It is part retrospective and prospective, going beyond a historical review to outline some ideas about important factors that drove the...