v0.6.0 (2026-08-19). Stage 1 moves from the BFGS search to the
closed-form HLIML estimator with hybrid boundary-search routing
(patches 0025-0037): usable Stage 1 cells rise 50.5% -> 66.0%
(141,824 -> 185,144 of 280,649; HLIML interior 62.4% of ok, Step 2
fallback 21.4%, boundary optima 16.2% with structurally unavailable
SEs, adjust codes 6/7/8), and sigma moves for the first time across
releases: median 2.878 -> 2.705 (IQR 1.63-5.71). Standard errors on
closed-form cells use an O(n)… See the full description on the dataset page:
https://huggingface.co/datasets/impex-machina/trade-elasticities.
