in silico
Phase 1 : In Silico Validation
- Objectif
- To kill the hypothesis cheaply by testing whether the ontology-augmented model can outperform a tuned baseline on synthetic spectral data, and to validate the core mechanism of semantic disambiguation before any wet-lab work.
- Coût estimé
- €1,500-3,000 (mostly personnel time)
- Durée estimée
- 4-8 weeks
- Critères de réussite
- MAPE reduction (relative) · Ontology-augmented model shows ≥20% relative reduction in MAPE vs. baseline for at least 2 of 3 metals (e.g., baseline 20% → augmented ≤16%) · (Calculate per-sample MAPE for each model on the test set; compute mean and relative difference.)
- Statistical significance · p-value < 0.05 from one-tailed paired t-test (μ_augmented < μ_baseline) · (Use scipy.stats.ttest_rel with alternative='less'.)
- Novel interferent recall · Recall ≥ 0.80 for detecting Co-containing samples (uncertainty > 95th percentile) · (Compute binary classification metrics (recall) using the uncertainty threshold.)
- On continue si
- All three success criteria are met (MAPE reduction, significance, and novel interferent recall).
- On arrête si
- The augmented model does not outperform baseline (p ≥ 0.05) OR recall < 0.60. This suggests the ontology priors are not providing useful inductive bias.
- On réoriente si
- If the baseline is already achieving MAPE < 10%, the test may be underpowered. Consider increasing spectral noise or adding more complex interferent mixtures. If the GNN fails to train, simplify the graph construction (e.g., use fully connected graph with attention).
- Risques
- Synthetic data is too “easy” (e.g., perfectly additive, no matrix effects), leading to overoptimistic results that don’t translate to real lab data.Probabilité : mediumParade : Add realistic noise, baseline drift, and random pH fluctuations (±0.1 units) to the synthetic data. Validate with a small set of real UV-Vis spectra if available.
- GNN implementation is complex and time-consuming, delaying the phase.Probabilité : mediumParade : Start with a simpler semantic attention layer (e.g., a transformer with ontology-derived attention masks) before moving to a full GNN. Use pre-built PyTorch Geometric examples.
- Ontology construction is too abstract and not directly usable by the GNN.Probabilité : lowParade : Define a clear mapping from ontology classes/properties to graph nodes/edges. Use a simple JSON schema for the ontology to avoid OWL complexity in the first iteration.