Skip to content

Latest commit

 

History

History
283 lines (253 loc) · 15.4 KB

File metadata and controls

283 lines (253 loc) · 15.4 KB

Citations

Every data source, paper, and external tool this project relies on, grouped by what it's used for. If you use this repo, cite the underlying data sources below in addition to this repo itself: they did the actual transcription and research work.

Real data sources

Two of these five are shipped directly in this repo (indus_website, CISI/mayig); the other three (Sangam Tamil, Sanskrit, Sumerian) are not, per their source licenses -- see each entry below for the converter script that regenerates them locally.

M77/IDF-80 (indusscript.in, RMRL/Indus Research Centre)

Source of data/m77_indusscript_real_corpus.csv (3,573 usable lines from 2,906 texts), the actual canonical M77 corpus (Mahadevan 1977, digitized as IDF-80) behind Rao et al. 2009 and Yadav et al. 2010 -- see README's "M77 obtained and verified" for the full account.

  • Portal: https://indusscript.in
  • Maintained by: Roja Muthiah Research Library (RMRL), Indus Research Centre, in collaboration with the Department of Archaeology, Government of Tamil Nadu.
  • Suggested acknowledgment (per the portal's own request): Mahadevan, Iravatham & Roja Muthiah Research Library (2021), The Indus Script Web Application (IM77/IDF80). https://indusscript.in
  • Access method: the portal has no public bulk-download button; this export was obtained via an authenticated (Google login) browser session, extracting the site's own Firestore backend directly via JavaScript. This is a real reproducibility limitation, stated plainly: a third party cannot rerun this exact extraction without their own login and browser access.
  • Verification: every specific record count, sign-occurrence count, and three individually worked examples (texts 1001, 1003, 1012) were independently recomputed from the raw JSON and confirmed exact before this data was used for anything. See the README section for the full list of checks.
  • What we use: non-empty (posnum != 0) records, keyed by the unique (textnum, sideline) pair, parsed by data/convert_m77_indusscript_to_csv.py. Signs are Mahadevan's own numbering (prefixed MSg in this project's schema to stay visibly distinct from other sign-numbering schemes used elsewhere in this project). Site, object type, and motif metadata are not present in this export.
  • Note on redistribution: as with the external-language corpora, the raw JSON/CSV export is not included in this repository; the converter script is.

yajnadevam/indus-website

Source of data/indus_website_real_corpus.csv (2,543 inscriptions, 592 signs, 1,622 with iconographic motif codes).

  • Repository: https://github.com/yajnadevam/indus-website
  • What we use: the SEAL, INSCRIPTION, GLYPHSEQUENCE, and ICONOGRAPHY tables from population-script.sql, parsed by data/convert_indus_website_sql_to_csv.py.
  • License: check the repository directly before redistributing beyond this project's use; no explicit data license was found at the time of integration.
  • Caveat: this repository is maintained by the same researcher (going by the GitHub handle "yajnadevam") behind a "cryptanalytic decipherment of the Indus script" claim (dated November 2024) proposing the script encodes post-Vedic Sanskrit. That specific decipherment claim has been publicly and substantively critiqued, including by the author's own later acknowledgment of errors in the original paper and procedures. This project does not use, endorse, or rely on that decipherment claim or any sign-to-meaning mapping from it. What this project uses is raw transcription data (which glyph appears where, on which seal, at which site), which is ordinary epigraphic fieldwork independent of the disputed interpretive claim. Users of this repo should form their own view of that dispute rather than take this project's use of the underlying data as an endorsement either way.
  • Corroborating detail: this corpus's scale (2,543 raw inscriptions before deduplication, 700 total glyph codes, 52 archaeological sites) matches the "ICIT/Yajnadevam digitization" described in the arXiv paper cited below, and this toolkit's own entropy analysis on it (3.26 bits, after correcting a reading-direction error) lands close to that paper's reported 3.23 bits.

mayig/indus-valley-script-corpus

Source of data/cisi_real_corpus.csv (179 inscriptions, 142 signs, all with a motif derived from the seal description).

  • Repository: https://github.com/mayig/indus-valley-script-corpus
  • What we use: the corpus/*/*.json files, a hand-transcription of a subset of Parpola's Corpus of Indus Seals and Inscriptions (CISI), parsed by data/convert_cisi_to_csv.py.
  • License: MIT (per the repository's LICENSE file).
  • Acknowledgment (from the source repository's own README): the author thanks Dr. Asko Parpola for the underlying CISI corpus, and acknowledges Dr. Andreas Fuls and Bryan K. Wells for related contributions to Indus script theory and pedagogy.
  • Note: this is explicitly a work-in-progress digitization (179 inscriptions transcribed as of integration, covering roughly the M-1 through M-199 range from Mohenjo-daro), not a complete corpus.

Sangam Literature Corpus (Old Tamil)

Source of data/tamil_real_corpus.csv (33,711 usable lines from 2,377 poems), the third real external-language calibration corpus (see README's "A third language, located and tried: Old Tamil").

  • Dataset: https://huggingface.co/datasets/starhopp3r/sangam
  • Underlying translations: Vaidehi Herbert, https://sangamtranslationsbyvaidehi.com
  • Citation: the dataset card requests crediting Vaidehi Herbert and linking to her site for any use.
  • License: the Old Tamil source texts are public domain (ancient works); Vaidehi Herbert's English translations, notes, glossaries, and Tamil prose explanations are her own copyright, all rights reserved, redistributed by the dataset for research and educational use with attribution. This project uses only the tamil_text column (the original Old Tamil verses); the meanings, notes, and english_translation columns are not used and are not redistributed.
  • What we use: tamil_text, tokenized as raw whitespace-separated orthographic words (NOT lemmatized -- no lemmatized digital Sangam corpus was found; see the README section above for what this limitation does to the results).
  • Note on redistribution: as with ETCSL and DCS, the derived CSV is not included in this repository; regenerate locally via data/convert_tamil_to_csv.py from your own copy of the dataset.

Digital Corpus of Sanskrit (DCS) / Rigveda

Source of data/dcs_sanskrit_real_corpus.csv (21,231 usable sentences from the Rigveda), the second real external-language calibration corpus (see README's "A second real language: Sanskrit").

  • Repository: https://github.com/OliverHellwig/sanskrit
  • Citation: Hellwig, Oliver. Digital Corpus of Sanskrit (DCS). Ongoing since 1999; open-sourced 2018. https://github.com/OliverHellwig/sanskrit
  • License: no explicit license file found in the repository at time of integration; the maintainer has repeatedly and publicly announced data releases (INDOLOGY mailing list, 2018-2025) specifically encouraging downstream NLP research use. Treated here as intended for reuse on that basis, but this should be confirmed against the repository's current terms before any redistribution beyond this project's own local, non-commercial use.
  • What we use: dcs/data/conllu/files/Ṛgveda/*.conllu, standard CoNLL-U format, the LEMMA column (field 3) specifically, parsed by data/convert_dcs_sanskrit_to_csv.py.
  • Note on redistribution: as with ETCSL, the raw CoNLL-U files and the derived CSV are not included in this repository; regenerate locally from a clone of the source repository.

Electronic Text Corpus of Sumerian Literature (ETCSL)

Source of data/etcsl_real_corpus.csv (33,338 usable lines from 394 literary compositions), used as a genuine external-language calibration corpus (see README's "Real external-language calibration").

  • Website: https://etcsl.orinst.ox.ac.uk
  • Citation: Black, J.A., Cunningham, G., Ebeling, J., Flückiger-Hawker, E., Robson, E., Taylor, J., and Zólyomi, G. The Electronic Text Corpus of Sumerian Literature. Oxford, 1998-2006. https://etcsl.orinst.ox.ac.uk
  • License: CC BY-NC-SA 3.0 (Attribution-NonCommercial-ShareAlike), distributed via the Faculty of Linguistics, Philology and Phonetics, University of Oxford (successor to the Oxford Text Archive's original hosting; the corpus's OTA handle migrated from ota.bodleian.ox.ac.uk to llds.ling-phil.ox.ac.uk at some point after this project's initial research, and a mirror is also available via LINDAT/CLARIAH-CZ, http://hdl.handle.net/11372/LRT-874).
  • What we use: the transliterations/*.xml files' <w lemma="..."> attributes, parsed by data/convert_etcsl_to_csv.py. The <w form="..."> attribute (exact inflected surface form, rather than dictionary lemma) is available as an alternative granularity; see that script's docstring for the methodological reasoning behind using lemma as the default.
  • Note on redistribution: the raw ETCSL XML files are NOT included in this repository (respecting the NC-SA license's terms and the project's small-file-footprint practice elsewhere); obtain them directly from the sources above and run the converter locally.

Foundational academic literature (methodology this toolkit implements)

  • Mahadevan, I. (1977). The Indus Script: Texts, Concordance and Tables. Archaeological Survey of India. The original M77 concordance and 417-sign catalog; not directly used as data here (not publicly downloadable at time of writing) but the methodological reference point for sign numbering and corpus filtering (EBUDS) throughout the field.
  • Rao, R. P. N., Yadav, N., Vahia, M. N., Joglekar, H., Adhikari, R., and Mahadevan, I. (2009). "Entropic Evidence for Linguistic Structure in the Indus Script." Science, 324(5931), 1165.
  • Rao, R. P. N., Yadav, N., Vahia, M. N., Joglekar, H., Adhikari, R., and Mahadevan, I. (2009). "A Markov Model of the Indus Script." PNAS, 106(33), 13685-13690. Source of the n-gram Markov modeling approach implemented in analysis/ngram.py.
  • Yadav, N., Joglekar, H., Rao, R. P. N., Vahia, M. N., Adhikari, R., and Mahadevan, I. (2010). "Statistical Analysis of the Indus Script Using n-Grams." PLOS ONE, 5(3), e9506. https://doi.org/10.1371/journal.pone.0009506 Source of the Zipf-Mandelbrot fitting, positional asymmetry analysis, log-likelihood significant-bigram testing, cross-validated perplexity, and the restoration-accuracy methodology (the top-90%-cumulative-mass criterion implemented in analysis/ngram.py's restoration_accuracy_top90mass()) that this toolkit reproduces. Open access under CC BY. No downloadable dataset was found attached to this paper; its corresponding authors, listed in the paper, are Nisha Yadav (y_nisha@tifr.res.in) and Ronojoy Adhikari (rjoy@imsc.res.in).
  • Rao, R. P. N., Yadav, N., Vahia, M. N., Joglekar, H., Adhikari, R., and Mahadevan, I. (2010). "Entropy, the Indus Script, and Language: A Reply to R. Sproat." Computational Linguistics, 36(4), 795-805. Response to the Farmer-Sproat-Witzel non-linguistic-symbol hypothesis; the conceptual basis for this toolkit's analysis/entropy.py comparisons against random and rigid-fixed controls.
  • Sinha, S., Izhar, A. M., Pan, R. K., and Wells, B. K. (2010). "Network Analysis of a Corpus of Undeciphered Indus Civilization Inscriptions Indicates Syntactic Organization." arXiv:1005.4997. https://arxiv.org/abs/1005.4997 Describes the Wells W09IMSc (3,896 artifacts, 695 signs) and WUCS (Wells Unique Complete Single-line, 1,821 sequences, 593 signs) datasets as an alternative corpus to M77, with a full sign-frequency appendix and concrete network statistics (reciprocity, connectivity, beginner/ender sign counts, both empirical and randomized-baseline). Those published statistics are directly used in experiments/wucs_comparison_test.py as an external validation point for this project's own corpus (see README's "External validation against an independently published corpus"); the earlier 2009 conference version of this work by an overlapping set of authors is a separate, distinct citation, not superseded by this one.
  • Farmer, S., Sproat, R., and Witzel, M. (2004). "The Collapse of the Indus-Script Thesis: The Myth of a Literate Harappan Civilization." Electronic Journal of Vedic Studies, 11(2). The non-linguistic-symbol hypothesis that motivated the entropy-based falsification approach this toolkit implements.
  • Anonymous or pseudonymous author (2026). "How Non-Linguistic Is the Indus Sign System? A Synthetic-Baseline Scorecard." arXiv:2604.17828. https://arxiv.org/abs/2604.17828 Source of the "ICIT/Yajnadevam digitization" description (1,916 deduplicated inscriptions, 584 unique signs, 11,110 tokens, 52 sites) that let us corroborate data/indus_website_real_corpus.csv's provenance, and of the specific synthetic-baseline methodology (heraldic and administrative null-model generators) that inspired this project's data/synthetic_civilizations.py and analysis/falsification.py. This paper's own data-availability statement says its data is available from the corresponding author upon request; we did not obtain it directly and instead independently found and verified the underlying corpus via yajnadevam/indus-website.

Other real-world sources referenced but not integrated

  • Palaniappan, S., and Adhikari, R. (2017). "Deep Learning the Indus Script." arXiv:1702.00523. Source of the vision/OCR pipeline whose trained weights live at https://github.com/tpsatish95/indus-script-ocr. Not used in this toolkit, which works on transcribed sign sequences, not seal photographs.
  • Wells, B. K. (2006). Epigraphic Approaches to Indus Writing. Harvard University. Source of the Interactive Corpus of Indus Texts (ICIT) described in this project's README as an unintegrated real-data lead.

Context on disputed or independently unverified claims

These are discussed in this project's development history and README for transparency, but nothing from them is used as data or methodology here:

  • Yajnadevam (2024). "A Cryptanalytic Decipherment of the Indus Script." Claims the script encodes post-Vedic Sanskrit. Publicly and substantively critiqued; the author later acknowledged errors in the original paper's procedures. See public discussion threads for detail; not cited further here because this project takes no position on the claim beyond noting its disputed status.
  • Pierson, T. K. (2026). "A Computational Decipherment Hypothesis for the Indus Script: 185 Proto-Dravidian Readings Validated Across Two Independent Corpora." Zenodo. DOI: 10.5281/zenodo.20414696. A self-published, not-yet-peer-reviewed preprint (repository: https://github.com/BitConcepts/glossa-lab) proposing a Proto-Dravidian decipherment. The repository is unusually transparent about its own audit process, including retracted claims, which is commendable, but the claim itself has not been independently peer-reviewed at time of writing. Not used as data or methodology here.

Software

  • NumPy, SciPy, pandas, Matplotlib: standard scientific Python stack, used throughout analysis/ and main.py.
  • No deep learning framework (PyTorch, TensorFlow) is used; models/transformer_mlm.py is a from-scratch NumPy implementation, by design, to keep this repo dependency-light and fully inspectable.