After reading the paper on approaches to uncertainty, it was interesting to see a case study of how these concepts are put into practice. In Approaches to Uncertainty, the authors outline the nature of uncertainty in spatial data. The authors outline two strains of uncertainty, one strain where the object is well defined and therefore the errors are probabalistic in nature. The other strain of uncertainty is when the object is poorly defined, which results in more vague and ambiguous forms of uncertainty. In Modelling vague places the authors describe a method of density modelling as an effective method of representing the uncertainty of a place name extent.
In Jones’ article, they discuss the difficulty of storing spatial information for vague place names like the Rockies, or a downtown, that are not strictly defined. The authors mention that when trying to determine how subjects conceptualize vague places, interviews are a powerful tool. They then go on to conclude that automatic web-harvesting is a better way to go, because it is clearly more time efficient. However there is still room for interviews in smaller scale studies.
For example, I found this article to be a good addition to a discussion on qualitative GIS that I had in GEOG 494. In the presented reading, a researcher had collected information through interviews of how safe a Muslim woman felt going about her daily activities through space post-911. Through her interviews, the researcher found that her subject’s definition of friendly space had shrunk in the post-911 society. I just bring up this example to show that not all uncertainty due to vague definitions of space in a GIS can be modelled using web-based knowledge or automated processes.
-anontarian