Soil moisture variability at the satellite pixel scale: implications for calibration/validation networks
Bibliographic record
Abstract
To ensure the ongoing accuracy of existing and future soil moisture satellites, 'in situ' calibration/validation must occur. This study seeks to maximize accuracy of an 'in situ' network while minimizing the costs typically associated with validation/calibration by determining the minimum number of sites required to characterize the mean soil moisture of a satellite pixel. Furthermore, calibration/validation costs can be further reduced by assessing the suitability of existing soil moisture monitoring stations for use as long term calibration/validation sites. In this case, two existing stations were assessed with only one proving accurate enough for use as a satellite validation/calibration station. This study also addressed the calls in recent literature (Wagner et al., 2007) to assess and compare the performance of satellite soil moisture retrieval algorithms in a variety of moisture conditions by assessing the performance of the Njoku (2005) and the Owe (2007) soil moisture retrieval algorithms.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.072 | 0.189 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.002 | 0.003 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".