Geographic Dimensions of Broadband Data Uncertainty

Abstract

Given the evolving nature of publicly available broadband data, the goal of this paper is to review sources of uncertainty in broadband provision data from the Form 477 database published by the Federal Communications Commission (FCC), which is the largest broadband database for the United States available to the public. This uncertainty analysis reveals that reporting thresholds understate broadband in rural areas serviced by smaller providers in the 1999-2004 ZIP code area dataset. In this same time series, the routine used to aggregate data to larger spatial units (i.e. counties) produces variations in the amount of autocorrelation detected by diagnostic spatial statistics. The amount of autocorrelation in the data also varies with the strategy implemented for interpolating suppressed data. This investigation also highlights the value of a spatial approach to visualizing and analyzing the impact of uncertainty on broadband availability.

Keywords: data uncertainty, broadband, FCC, spatial data