# Implementation Summary: Evaluation Improvements

**Date**: 2025-01-XX  
**Status**: Core Features Implemented, Integration In Progress

## ✅ Completed Implementations

### 1. Chain-Length Stratification for Coreference ✅
- **File**: `src/eval/coref_metrics.rs`
- **Implementation**: 
  - Added `compute_chain_length_stratified()` function
  - Integrated into `CorefEvaluation::compute()`
  - Automatically computes per-chain-length F1 (long/short/singleton)
  - Updated `Display` to show chain-length breakdown
- **Usage**: Automatically computed for all coreference evaluations

### 2. Improved Familiarity Computation ✅
- **File**: `src/eval/types.rs`
- **Implementation**:
  - Enhanced `LabelShift::from_type_sets()` with improved string similarity
  - Added `from_type_sets_with_embeddings()` for true semantic similarity
  - Uses Levenshtein distance + substring matching for better heuristic
  - Supports embedding-based computation when embeddings are available
- **Usage**: Can be called with or without embeddings

### 3. Boundary Error Documentation ✅
- **File**: `src/eval/ner_metrics.rs`
- **Implementation**: Added comprehensive documentation explaining:
  - Greedy matching behavior
  - Why boundary errors are not double-penalized in our implementation
  - How boundary errors differ from complete misses
- **Usage**: Documentation available in function docs

### 4. TaskEvalConfig and TaskEvalResult Expansion ✅
- **File**: `src/eval/task_evaluator.rs`
- **Implementation**:
  - Added `robustness`, `compute_familiarity`, `temporal_stratification`, `confidence_intervals` flags
  - Added `label_shift`, `robustness`, `stratified`, `confidence_intervals` fields to results
  - Added `StratifiedMetrics`, `MetricWithCI`, `ConfidenceIntervals` types
- **Usage**: Structures ready for integration

### 5. Helper Functions ✅
- **File**: `src/eval/task_evaluator.rs`
- **Implementation**:
  - `compute_familiarity_if_zero_shot()`: Computes familiarity for zero-shot backends
  - `compute_confidence_intervals()`: Computes confidence intervals (placeholder implementation)
- **Usage**: Called in `evaluate_combination()` when flags are enabled

## 🚧 Partially Implemented (Structures Ready, Full Integration Pending)

### 6. Familiarity Integration
- **Status**: Helper function exists and is called
- **Remaining**: Need to ensure it's called for all zero-shot backends, report in outputs

### 7. Robustness Testing Integration
- **Status**: Structure ready, feature-gated properly
- **Remaining**: Need to call `RobustnessEvaluator` in `evaluate_ner_task()` when enabled

### 8. Temporal Stratification
- **Status**: Structure ready in `StratifiedMetrics`
- **Remaining**: Need to add temporal metadata to datasets, compute stratification

### 9. Expanded Stratified Metrics
- **Status**: Structure ready with `by_surface_form`, `by_mention_char`
- **Remaining**: Need to compute these metrics in evaluation functions

### 10. Confidence Intervals
- **Status**: Helper function exists (placeholder)
- **Remaining**: Need proper variance computation from per-example scores

## ⏳ Not Started

### 11. KB Version Tracking
- **Status**: Not started
- **Required**: Add KB version metadata, URI validation, emerging entity separation

## Testing Status

- [x] Code compiles successfully
- [ ] Chain-length stratification tests
- [ ] Familiarity computation tests
- [ ] Integration tests for new features

## Next Steps

1. **Complete Robustness Integration**: Add robustness testing call in `evaluate_ner_task()`
2. **Complete Temporal Stratification**: Add temporal metadata support
3. **Complete Stratified Metrics**: Compute surface form and mention characteristics
4. **Improve Confidence Intervals**: Compute from per-example scores
5. **Add Tests**: Comprehensive test coverage for new features
6. **Update Documentation**: User-facing docs for new evaluation features

## Files Modified

1. `src/eval/coref_metrics.rs` - Chain-length stratification
2. `src/eval/types.rs` - Improved familiarity computation
3. `src/eval/ner_metrics.rs` - Boundary error documentation
4. `src/eval/task_evaluator.rs` - Config/result expansion, helper functions
5. `docs/EVALUATION_CRITICAL_REVIEW.md` - Analysis document
6. `docs/IMPLEMENTATION_STATUS.md` - Status tracking
7. `docs/IMPLEMENTATION_SUMMARY.md` - This file

## Key Achievements

✅ **Research-Aligned**: All implementations follow latest research findings  
✅ **Backward Compatible**: New features are opt-in via config flags  
✅ **Feature-Gated**: Robustness testing properly gated behind `eval-advanced`  
✅ **Well-Documented**: Comprehensive documentation added  
✅ **Type-Safe**: All new types properly defined and serializable

