The Wisconsin Department of Agriculture, Trade, and Consumer Protection is charged with ensuring a safe and high-quality supply of milk from the state’s dairy farms. Accordingly, the state regularly tests milk samples from farms for measures of safety and quality, as well as sending Sanitarians to inspect operating conditions. The schedule of on-site inspections is determined by a farm’s performance in its previous inspection. This system was established to incentivize improvements in inspection performance. However, multiple inspection frequencies within a Sanitarian’s assigned territory cause inefficiencies in travel. After 20 years of performance-based inspections the state has begun to wonder: could Sanitarians inspect on a universal frequency to improve system efficiency without jeopardizing the safety and quality of the state’s milk supply? In order to test this hypothesis, we regressed the number of inspection debits per inspection a farm received on the number of inspections that the farm received in the previous year. Included in our model were also binary variables for Sanitarian, inspection year, and inspection month.
