1. http://fia.fs.fed.us/ Adaptive data correction at remeasurement: What to do when errors are discovered? 2011 National FIA User Group Meeting Sacramento, CA March 8-10, 2011 Bill Burkman Southern Research Station FIA Program Manager

2. http://fia.fs.fed.us/ Objectives of Presentation Define the issue Possible solutions Implications of the solutions Discussion and questions

3. http://fia.fs.fed.us/ Quality Assurance Program Field data collection: –Crew Training –National Field Guide –Quality control data collection –Corrective action Data processing checks: –Range or valid code checks –Logic checks –Analyst review of draft output For more detailed information – Phyllis Adams, National FIA QA coordinator

4. http://fia.fs.fed.us/ Current data correction procedures : Field data collection activities Field data recorder procedures: –Crews are given some information: dbh, azimuth, species, etc. –Some variables are “hidden” ; “hidden variables are only shown to crew if there is a logic check discrepancy Data checks: –Range or valid code checks –Logic checks: compare two variables from T2 or compare same variable from T1 and T2 Crews have option of providing note

5. http://fia.fs.fed.us/ Current data correction procedures : Data processing activities Same checks are evaluated during data processing Additional edits are evaluated during data processing Analyst review of draft data – QA tools in development Some checks are geo-spatial Estimates of change are impacted by current processing; generally based on T1 values Some major issues are sent back to the field for verification

6. http://fia.fs.fed.us/ Current data correction procedures : Issues Unusual results can result from basing on T1 values: –Reserve status – e.g. removals from reserved land –Stand origin – e.g. pine plantation changing to natural hardwood stand –Land use changes - –Species When to change and how far back to go? What happens if “fixed” data does not match previously published information?

7. http://fia.fs.fed.us/ Solutions??? Assume T2 is correct and fix T1 – possible but may not be practical in all cases Provide additional tools and checks in data recorder program so T2 crew can update Complete QA tool development and deploy Other solutions?

8. Discussion and Questions http://fia.fs.fed.us/