Open-Quant · Sean-Koval · Aug 31, 2026 · Aug 31, 2026
diff --git a/docs-site/package-lock.json b/docs-site/package-lock.json
diff --git a/docs-site/src/content/docs/modules/adapters.md b/docs-site/src/content/docs/modules/adapters.md
@@ -3,7 +3,7 @@ title: "adapters"
 description: "Polars DataFrame adapters for signals, events, weights, backtest curves, and streaming buffers."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/backtest-statistics.md b/docs-site/src/content/docs/modules/backtest-statistics.md
@@ -3,7 +3,7 @@ title: "backtest_statistics"
 description: "Performance diagnostics for strategy returns and position trajectories."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/backtesting-engine.md b/docs-site/src/content/docs/modules/backtesting-engine.md
@@ -3,7 +3,7 @@ title: "backtesting_engine"
 description: "Backtesting core with walk-forward, purged CV, and combinatorial purged CV (CPCV) workflows."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/bet-sizing.md b/docs-site/src/content/docs/modules/bet-sizing.md
@@ -3,7 +3,7 @@ title: "bet_sizing"
 description: "Transforms model confidence and constraints into executable position sizes."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/cla.md b/docs-site/src/content/docs/modules/cla.md
@@ -3,7 +3,7 @@ title: "cla"
 description: "Critical Line Algorithm implementation for constrained mean-variance optimization."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/codependence.md b/docs-site/src/content/docs/modules/codependence.md
@@ -3,7 +3,7 @@ title: "codependence"
 description: "Dependence metrics beyond linear correlation for feature and asset relationships."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/combinatorial-optimization.md b/docs-site/src/content/docs/modules/combinatorial-optimization.md
@@ -3,7 +3,7 @@ title: "combinatorial_optimization"
 description: "AFML Chapter 21 integer-encoded optimization and trajectory state-space tooling with exact baselines and solver adapters."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/cross-validation.md b/docs-site/src/content/docs/modules/cross-validation.md
@@ -3,7 +3,7 @@ title: "cross_validation"
 description: "Purged cross-validation utilities designed for label overlap and leakage control."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/data-structures.md b/docs-site/src/content/docs/modules/data-structures.md
@@ -3,7 +3,7 @@ title: "data_structures"
 description: "Constructs standard/time/run/imbalance bars from trade streams."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/data.md b/docs-site/src/content/docs/modules/data.md
@@ -3,7 +3,7 @@ title: "data"
 description: "OHLCV loading, cleaning, calendar alignment, and data quality reporting."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/ef3m.md b/docs-site/src/content/docs/modules/ef3m.md
@@ -3,7 +3,7 @@ title: "ef3m"
 description: "Moment-based mixture fitting utilities for two-normal components."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/ensemble-methods.md b/docs-site/src/content/docs/modules/ensemble-methods.md
@@ -3,7 +3,7 @@ title: "ensemble_methods"
 description: "Bias/variance diagnostics and practical bagging-vs-boosting ensemble utilities."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/etf-trick.md b/docs-site/src/content/docs/modules/etf-trick.md
@@ -3,7 +3,7 @@ title: "etf_trick"
 description: "Synthetic ETF and futures roll utilities for realistic PnL path construction."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/feature-diagnostics.md b/docs-site/src/content/docs/modules/feature-diagnostics.md
@@ -3,7 +3,7 @@ title: "feature_diagnostics"
 description: "Feature importance diagnostics: MDI, MDA, SFI, PCA orthogonalization, and substitution-effect analysis."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/feature-importance.md b/docs-site/src/content/docs/modules/feature-importance.md
@@ -3,7 +3,7 @@ title: "feature_importance"
 description: "Feature ranking methods: MDI, MDA, and single-feature importance with PCA diagnostics."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/filters.md b/docs-site/src/content/docs/modules/filters.md
@@ -3,7 +3,7 @@ title: "filters"
 description: "CUSUM and z-score event filters for event-driven sampling."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/fingerprint.md b/docs-site/src/content/docs/modules/fingerprint.md
@@ -3,7 +3,7 @@ title: "fingerprint"
 description: "Model fingerprinting for linear, non-linear, and pairwise feature effects."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/fracdiff.md b/docs-site/src/content/docs/modules/fracdiff.md
@@ -3,7 +3,7 @@ title: "fracdiff"
 description: "Fractional differentiation to improve stationarity while retaining memory."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/hcaa.md b/docs-site/src/content/docs/modules/hcaa.md
@@ -3,7 +3,7 @@ title: "hcaa"
 description: "Hierarchical Clustering Asset Allocation variant with cluster-level constraints."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/hpc-parallel.md b/docs-site/src/content/docs/modules/hpc-parallel.md
@@ -3,7 +3,7 @@ title: "hpc_parallel"
 description: "AFML Chapter 20 atom/molecule execution utilities with serial/threaded modes and partition diagnostics."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/hrp.md b/docs-site/src/content/docs/modules/hrp.md
@@ -3,7 +3,7 @@ title: "hrp"
 description: "Hierarchical Risk Parity allocation with recursive bisection."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/hyperparameter-tuning.md b/docs-site/src/content/docs/modules/hyperparameter-tuning.md
@@ -3,7 +3,7 @@ title: "hyperparameter_tuning"
 description: "Leakage-aware grid/randomized hyper-parameter search with purged CV and weighted scoring."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/index.md b/docs-site/src/content/docs/modules/index.md
@@ -3,7 +3,7 @@ title: "Module Reference Index"
 description: "Full OpenQuant module documentation index with AFML-aligned summaries."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/labeling.md b/docs-site/src/content/docs/modules/labeling.md
@@ -3,7 +3,7 @@ title: "labeling"
 description: "Triple-barrier event labeling and metadata generation."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/microstructural-features.md b/docs-site/src/content/docs/modules/microstructural-features.md
@@ -3,7 +3,7 @@ title: "microstructural_features"
 description: "Price-impact, spread, entropy, and flow toxicity estimators."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/onc.md b/docs-site/src/content/docs/modules/onc.md
@@ -3,7 +3,7 @@ title: "onc"
 description: "Optimal Number of Clusters utilities for clustering stability and allocation workflows."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/pipeline.md b/docs-site/src/content/docs/modules/pipeline.md
@@ -3,7 +3,7 @@ title: "pipeline"
 description: "End-to-end AFML research pipeline: events → signals → portfolio → risk → backtest with leakage checks."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/portfolio-optimization.md b/docs-site/src/content/docs/modules/portfolio-optimization.md
@@ -3,7 +3,7 @@ title: "portfolio_optimization"
 description: "Mean-variance and constrained allocation methods with ergonomic APIs."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/research.md b/docs-site/src/content/docs/modules/research.md
@@ -3,7 +3,7 @@ title: "research"
 description: "Synthetic dataset generation and flywheel research iteration with cost modeling and promotion gates."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/risk-metrics.md b/docs-site/src/content/docs/modules/risk-metrics.md
@@ -3,7 +3,7 @@ title: "risk_metrics"
 description: "Portfolio and return-distribution risk measures for downside control."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/sample-weights.md b/docs-site/src/content/docs/modules/sample-weights.md
@@ -3,7 +3,7 @@ title: "sample_weights"
 description: "Sample weighting utilities for overlapping event structure."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/sampling.md b/docs-site/src/content/docs/modules/sampling.md
@@ -3,7 +3,7 @@ title: "sampling"
 description: "Indicator matrix and sequential bootstrap tooling."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/sb-bagging.md b/docs-site/src/content/docs/modules/sb-bagging.md
@@ -3,7 +3,7 @@ title: "sb_bagging"
 description: "Sequentially bootstrapped bagging classifiers/regressors."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/strategy-risk.md b/docs-site/src/content/docs/modules/strategy-risk.md
@@ -3,7 +3,7 @@ title: "strategy_risk"
 description: "AFML Chapter 15 strategy-viability diagnostics based on precision, payout asymmetry, and bet frequency."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/streaming-hpc.md b/docs-site/src/content/docs/modules/streaming-hpc.md
@@ -3,7 +3,7 @@ title: "streaming_hpc"
 description: "AFML Chapter 22 streaming analytics utilities for low-latency early-warning metrics with bounded-memory incremental state."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/structural-breaks.md b/docs-site/src/content/docs/modules/structural-breaks.md
@@ -3,7 +3,7 @@ title: "structural_breaks"
 description: "Regime change and bubble diagnostics (Chow, CUSUM variants, SADF)."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/synthetic-backtesting.md b/docs-site/src/content/docs/modules/synthetic-backtesting.md
@@ -3,7 +3,7 @@ title: "synthetic_backtesting"
 description: "Synthetic-data OTR backtesting with O-U calibration, PT/SL mesh search, and stability diagnostics."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/util-fast-ewma.md b/docs-site/src/content/docs/modules/util-fast-ewma.md
@@ -3,7 +3,7 @@ title: "util::fast_ewma"
 description: "Fast EWMA primitive shared across feature and volatility routines."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:

diff --git a/docs-site/src/content/docs/modules/util-volatility.md b/docs-site/src/content/docs/modules/util-volatility.md
@@ -3,7 +3,7 @@ title: "util::volatility"
 description: "Volatility estimators used across labeling and risk workflows."
 status: generated
 generated_from: src/data/moduleDocs.ts
-last_generated: '2026-08-30'
+last_generated: '2026-08-31'
 banner:
   content: '<span class="doc-status doc-status--generated">Generated</span> Assembled automatically from <code>moduleDocs.ts</code>. No human has reviewed this page.'
 audience:
@@ -13,7 +13,7 @@ module: "util::volatility"
 api_surface: "both"
 rust_api:
   - "get_daily_vol"
-  - "get_parksinson_vol"
+  - "get_parkinson_vol"
   - "get_garman_class_vol"
   - "get_yang_zhang_vol"
 sidebar:
@@ -50,7 +50,7 @@ where $\sigma_o^2$ is the overnight (close-to-open) variance, $\sigma_c^2$ the o
 
 ```rust
 use chrono::{Duration, NaiveDateTime};
-use openquant::util::volatility::{get_daily_vol, get_parksinson_vol};
+use openquant::util::volatility::{get_daily_vol, get_parkinson_vol};
 
 let t0 = NaiveDateTime::parse_from_str("2024-01-02 00:00:00", "%Y-%m-%d %H:%M:%S")?;
 let close: Vec<(NaiveDateTime, f64)> = (0..300)
@@ -62,7 +62,7 @@ let low: Vec<f64> = close.iter().map(|(_, p)| p - 0.4).collect();
 // Close-to-close EWMA vol on a timestamped series; `lookback` is the EWMA span.
 let daily = get_daily_vol(&close, 100);
 // Parkinson uses the high/low range, so it needs no timestamps — `window` bars.
-let parkinson = get_parksinson_vol(&high, &low, 20);
+let parkinson = get_parkinson_vol(&high, &low, 20);
 
 println!("daily vol tail = {:?}", daily.last());
 println!("parkinson vol tail = {:?}", parkinson.last());
@@ -73,14 +73,14 @@ println!("parkinson vol tail = {:?}", parkinson.last());
 ### Python API
 
 - `volatility.get_daily_vol`
-- `volatility.get_parksinson_vol`
+- `volatility.get_parkinson_vol`
 - `volatility.get_garman_class_vol`
 - `volatility.get_yang_zhang_vol`
 
 ### Rust API
 
 - `get_daily_vol`
-- `get_parksinson_vol`
+- `get_parkinson_vol`
 - `get_garman_class_vol`
 - `get_yang_zhang_vol`