A Proposal to estimate the roaming–dog Total in an urban area through a PPSWOR spatial sampling with sample size greater than two

  • Ornella Giambalvo
  • Roverto Sichera
Keywords: PPS sampling, design–based variance estimation, inclusion probability, MonteCarlo estimation, roaming dogs


Dogs roaming in urban areas constitute an issue for public order, hygiene and health. Proper planning of actions for health and security control and allocation of financial funds require the knowledge of the roaming–dog–population size in a given urban area. Unfortunately, a reliable statistical procedure aimed to measure such population is not available yet in literature. This paper presents a simple, reproducible survey sampling procedure to estimate the
number of roaming dogs in an urban area through the description of a real study carried out on a restricted area of the city of Palermo, in southern Italy. A sample of areas is drawn by means of a drawn–by–drawn spatial sampling with probabilities proportional to the size and without replacement (PPSWOR). As inclusion probabilities are not available in closed form, they are estimated by Monte Carlo approach, which is of simple implementation and permits design-based variance estimation even when first-order inclusion probabilities are unknown.


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