title: The importance of type II error and falsifiability.
abstract: Before intergovernmental consensus under the Rio Declaration in 1992, ignorance of type I errors had been disfavored in science. However, the Precautionary Principle (PP) counsels the avoidance of type II errors, rather than of type I errors. We need a new academic code for the PP. The risk of extinction has usually been evaluated based on conservative estimates of the present population size. I define the weight of evidence as the extinction risk of Japanese vascular plants based on unbiased estimates. Catch quotas in the fisheries are usually decided by precautionary approach. I calculate the long-term yield and risk of stock collapse under a simple stock dynamics model. The weight of evidence depends on the frequency of grids with size unknown. In a few plant species, rankings based on conservative estimates have differed from rankings based on unbiased estimates. In fishery management, a catch quota based on a precautionary approach proved neither sufficient nor necessary to avoid stock collapse. The precautionary approach is one of the reasons that prevent us from maximizing a sustainable yield. We need to clarify the end-point of risks, and check whether it is necessary to adopt a PP. We can obtain the weight of evidence that is measured under unbiased estimates, while the risk based on a PP is measured under conservative estimates.
authors.affiliation: Ocean Research Institute, University of Tokyo, Japan. matsuda@ynu.ac.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Matsuda
mesh_terms: D000818:Animals; D044822:Biodiversity; D004781:Environmental Exposure / Q000009:adverse effects / Q000517:prevention & control*; D004782:Environmental Health; D004785:Environmental Pollutants / Q000009:adverse effects*; D005398:Fisheries; D006801:Humans; D007564:Japan; D011237:Predictive Value of Tests; D011322:Primary Prevention / Q000458:organization & administration*; D018570:Risk Assessment; D012680:Sensitivity and Specificity
chemical_list: D004785:Environmental Pollutants