Reference material, analysis code and derived measurements for "Group Differences in Jitter and Shimmer Are Partly Manufactured by the Harmonics-to-Noise Ratio"

Supporting deposit for a study of measurement validity in clinical voice analysis, and for the accompanying book "The Room in the Voice". Every numerical claim in the paper is produced by a script included here. The deposit contains three things. CODE. Python scripts implementing the electroglottographic ground truth and its acceptance gates, the response functions of jitter, shimmer, HNR, cepstral peak prominence, formants and nonlinear measures, the manufactured-difference experiments, and the classifier tests. The script verify_manuscript.py regenerates every number in the paper in a single pass. REFERENCE MATERIAL (refmat v0.7). 930 synthetic audio files across five task classes (sustained vowel, nonlinear vowel, cough, breathing, speech), 186 specimens each, generated deterministically from seeds. manifest.csv carries a SHA-256 for every file; truth.csv carries the full generator parameters and the realised values. The hash is computed over the decoded audio samples and the sample rate, not over the raw bytes of the WAV container. All 930 verify. Domain of validity: this material is a legitimate reference for the vocal tract (formant frequencies and bandwidths), for source amplitude (shimmer) and for regime (bifurcation, chaos). It is NOT a valid reference for the precision ceiling of source period (jitter), where the sign of the response-versus-HNR relationship comes out backwards against real speech. DERIVED MEASUREMENTS. One row per recording, no audio: EGG-derived true jitter and shimmer, acoustic measures, HNR and f0 for five vowel and pitch conditions, plus the caches for each audit. These allow every analysis to be reproduced without re-processing any recordings. NOT INCLUDED: the Saarbruecken Voice Database recordings. They belong to the Institut fuer Phonetik, Universitaet des Saarlandes, are distributed under their own terms, and must be obtained from that source. Only numeric measurements derived from them appear here. Licences: code MIT; reference material, derived measurements and figures CC BY 4.0. Full documentation is in README.md.