Clarification of whp in the specification

Project:NAADSM
Version:4.0.5
Component:Documentation
Category:feature request
Priority:not yet set
Assigned:unassigned
Status:ready to commit
This relates to scenario #2426 posted on the scenario page. A WHP curve that starts on day 1 produced higher than expected daily adequate contacts. I think this is because WHP for a given day is interpolated between that day and the previous day. I originally created the curve starting on day 1 because the WHP output in the the within herd disease spread model starts on day 1. When I changed the curve to start on day 0 with 0% whp on that day, the results were as expected. Should a line be added to the specification reminding users to start their relational functions for WHP on day 0? The scenario is attached. A more detailed description can be found on the scenario page, #2426.
Description
AttachmentSize
whp10day_direct_100unit.mdb1.56 MB

Comments

#1

I went through the various places relational charts are used in the model.

Infected prevalence and infectious prevalence in disease-model

  • The input curve for these parameters should go from 0 to 1 on the x-axis. The curve will be stretched to fit the combined number of days the herd will spend in the latent, subclincal, and clinical states, and then the actual prevalence value on a given day is found by interpolation. Figure A3-2 in the model specification v2.0.0 document does a better job explaining this than I am doing here!
  • Note that if you don't fit your input curve between 0 and 1 on the x-axis, that's OK. If for example your input curve goes between 0 and 14, the C code will scale it down into the interval 0-1 before running.

Movement control in contact-spread-model

  • Specification says “vs. days since the first detection”
  • x-axis 0 = up to & including day of first detection. Note that this value applies even before the first detection. Normally people use (x=0,y=1) as the first point on their movement control chart, to indicate that up to & including the day of first detection, contacts happen at their “normal” rate. (A multiplier of 1 leaves the “normal” value unchanged.)
  • x-axis 1 = the day after the first detection

Probability of detection in detection-model

  • Specification says “vs. days the unit has been Infectious Clinical”
  • x-axis 0 = the first day the unit is infectious clinical
  • x-axis 1 = the second day the unit is infectious clinical

Probability of reporting in detection-model

  • Specification says “vs. days since the first detection”
  • x-axis 0 = up to & including the day of the first detection. Note that this value applies even before the first detection. This is often used to influence how early or how late the first detection occurs.
  • x-axis 1 = the day after the first detection

Vaccination and destruction capacity in resources-and-implementation-of-controls-model

  • Specification says “vs. days since the first detection”
  • x-axis 0 = the first day vaccinations/destructions can possibly be done (that is, the day after the first detection)
  • Not sure why this is different from the other charts that say “vs. days since the first detection”. But I looked back at older versions and it’s been that way all along. Should we change it so that x-axis 1 = the day after the first detection, for consistency?

#2

Thanks, Neil. These are helpful.

#3

Status:active» ready to commit