Skip to main content

Using Models to Estimate Hog and Pig Inventories Proceedings of a Workshop (2019) / Chapter Skim
Currently Skimming:

9 Discussion of Modeling
Pages 63-68

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 63...
... This approach allows the dynamics of the model to change, for example by using hidden Markov models. She also observed that collaboration with the Animal and Plant Health Information Service (APHIS)
Read the entire page →
From page 64...
... Such estimates provide information about how well the model is working. In answer to her question about how many data points are used to fit models, Luca Sartore replied the SWARCS model uses the entire time series of monthly and quarterly data from 2008 to the current quarter to prepare model estimates for the current quarter.
Read the entire page →
From page 65...
... Lee Schulz asked about the potential implications of a bottom-up approach given that external slaughter data, not available at the state level, are used to correct for biases in the survey data. Ensor agreed that this poses a constraint.
Read the entire page →
From page 66...
... These are smaller than the National Animal Health Reporting System studies, so aggregate information is limited to regional or national-level groupings, such as a slaughterhouse-based level estimate rather than a state-level estimate. Ensor asked about opportunities for a spatial temporal modeling approach with simultaneous estimation of state and national information.
Read the entire page →
From page 67...
... How to get enough data for estimation is a puzzle, he commented. Sartore agreed, adding that the Markov switching model might also be useful to directly model the monthly estimates for pig crop and sows farrowing and also for modeling survival rates.
Read the entire page →

Key Terms

  • hidden markov
  • state level
  • markov model
  • slaughter data
  • entire time

  • animal health
  • data limitations
  • pork board
  • modeling efforts
  • current quarter

  • linear model
  • auxiliary information
  • prior information
  • biological dynamics
  • dynamics occur

  • survival rates
  • generalized linear
  • national animal
  • slud asked
  • veterinarian data

  • data monthly
  • currently incorporated
  • sartore agreed
  • external slaughter
  • information service

  • past time
  • efforts described
  • size hog
  • computationally manageable
  • disease traceability


    • This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
    More information on Chapter Skim is available.