A Statistical Method to Construct Confidence Sets on Carrion Insect Age from Development Stage

  • Lynn R. LaMotte
  • Amanda L. Roe
  • Jeffrey D. Wells
  • Leon G. Higley


The age of a carrion insect associated with a corpse may represent a minimum postmortem interval. No method has been proposed before for constructing a confidence set on age based on development stage modeled as a categorical response. This paper illustrates the application of exact p values, first developed for succession data, to construct a confidence set on a carrion insect’s age based only on its development stage. It uses published development data for Lucilia sericata, with individuals reared at different temperatures pooled into sets of similar age as indexed in accumulated degree hours. Rates of coverage of true ages, assessed using each insect as a singleton holdout sample, were greater than the nominal 95% level.


Calibration Inverse prediction Categorical response Outlier detection Forensic entomology Lucilia sericata 



This project was supported by Award Nos. 2013-DN-BX-K042 (LRL and JDW) and 2010-DN-BX-K231 (LGH), awarded by the National Institute of Justice, Office of Justice Programs, US Department of Justice. The opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect those of the Department of Justice.


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Copyright information

© International Biometric Society 2017

Authors and Affiliations

  1. 1. LSU Health Sciences CenterNew OrleansUSA
  2. 2.College of Saint MaryOmahaUSA
  3. 3.Florida International UniversityMiamiUSA
  4. 4. University of Nebraska - LincolnLincolnUSA

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