October 19, 2017

GIS Analysis as a Research Communication Tool

The power of geospatial analysis lies in the new ways it provides to look at datasets and the relations among them. It allows you to explore more nuanced questions and discover correlations previously hidden. Used properly, geographic information system (GIS) tools can increase the saliency of a policy issue by expressing your argument visually and often much more effectively. Below is my recent experience in using GIS tools to broaden the audience for my research.

Property Assessment Disparities

Municipalities across the country are under fiscal duress due to cuts in state/federal aid, property tax levy limits, and rising employee fringe benefit costs. Often limited in their ability to generate new revenue streams, municipalities have become overly dependent on property taxes to “keep the lights on”.

Taxes are always a contentious issue and nobody wants to pay more than their fair share. To get a sense of how equitable the property tax burden was in Milwaukee, a city wrestling with all of the challenges noted above, I analyzed 33,000 property sales transactions over a 10-year period and compared them with their corresponding assessment values. By regressing the assessment value/sales price ratio on a host of predictors including building condition, lot size, geographic location, etc., I was able to get a sense of how equitable the city’s property taxation system is. While the findings presented an interesting disparity in who was paying their fair share, the results were neither accessible to the average citizen nor actionable for the policy maker. They required an understanding of my model specification and an ability to interpret coefficients expressed in terms of log odds. [Read more…]