A Formula for Revitalization Continued from page 31 the size of the site increases and as the distance or travel time for the consumer to the site decreases. [The Huff model was developed by Dr. David Huff of the University of Texas and first published in 1963. To learn more about the Huff model, see “Parameter Estimation in the Huff Model” by David L. Huff in the October–December 2003 issue of ArcUser magazine.] Once Delta established the geographic market area, it could conduct a more detailed evaluation of consumer spending and identify target retail tenants for further analysis. However, at this juncture, the The Hershey Press Building on Chocolate Avenue was recently renovated. analysis had focused on general retail spending. With an estimate from EDSA regarding the contiguous land area in the downtown that was available for development, the Delta team approached the analysis by assuming that this land could be developed into Hershey Square, a town center with leasable retail space that could compete with surrounding suburban retail centers. Bringing the Formula to Life Applying Hershey-specific assumptions to the Huff model gave a clearer picture of the local market. Those assumptions and the Delta team’s input for the model included the following five components: 1. The Huff model substituted Esri’s census block group polygons as the “consumers” and used the estimated total annual consumer spending for retail goods from Business Analyst’s demographic data as the data field to be summarized for each block group in the model results. 2. EDSA provided a preliminary assumption of the number of square feet that could physically be developed on the available contiguous parcels identified for redevelopment in the downtown area. This estimate represented the attractiveness factor, the potential Gross Leasable Area (GLA) of Hershey Square in the formula shown to the left. Consumer Probability = Potential Gross Leasable Area of Hershey Square Sum of Gross Leasable Area of Hershey Square AND of Competitive Centers Distance from Consumer to Hershey Square, Multiplied by a Distance Decay Factor Sum of Distance from Consumer to Hershey Square AND to Competitive Centers, Multiplied by a Distance Decay Factor The Huff model modified with Hershey-specific assumptions 32 ArcUser Summer 2010 www.esri.com