The State College Change Through Time project took the initial steps of georeferencing and mosaicing the scanned maps. Information about the 4,000 buildings was extracted by hand using ArcGIS Desktop. Historical photographs from Penn State’s Eberly Family Special Collections Library were linked to individual buildings for each time-period where available to give context to the map and to also make these resources geographically discoverable. Advertisements for local businesses were harvested from historical publications and linked to the buildings that businesses once occupied. When brought together in this map series, these resources paint an interactive and vivid picture of what campus and town were like, and the dynamic growth that Penn State and State College experienced during the early part of the 20th Century. These maps also provide data about campus and town in geographic context that can be repurposed for other research goals.
Data fusion is a contemporary idea that multiple data sources can be combined to create more complete, accurate or useful information. The value of data fusion applies to historical data as well as modern, although it is rarely applied with a historical focus. In this project, we demonstrate the fusion of two highly detailed historical datasets to produce spatially-explicit demographic maps of the community of State College, PA for two time-periods (1920 and 1930).
Historical spatial data came from building footprints digitized off of Sanborn Fire Insurance Maps, while the demographic information came from manuscript U.S. Census records accessible through Ancestry.com (library-edition), and digitized Penn State student directories.
Historical data is often messy and we used ABBY FineReader OCR, and regular expressions as implemented in the grep library of R to prepare the data.
Following data preparation, 72% of 3,144 historical 1920 demographic records were matched to a specific building location whereas 88% of 1930 records were matched. The results are spatially-explicit datasets of demographic information that can be used to visualize the spatial dimensions of population and socio-cultural change through time.
he Sanborn Maps® database is a project of the Digital Library of Georgia as part of Georgia HomePLACE. The project is supported with federal LSTA funds administered by the Institute of Museum and Library Services through the Georgia Public Library Service, a unit of the Board of Regents of the University System of Georgia. The maps represented are from the University of Georgia Libraries Map Collection.