# What has happened since Grieve et al. (2019)

Searches run up to 14 Sept. 2026 by web search and page fetch (quod.lib.umich.edu, hathitrust, loc.gov, books.google.com, web.archive.org and atlasobscura.com returned 403 or were unreachable). Queries: "Bixby letter" with Hay/authorship/n-gram/Grieve/replication/critique/stylometry and year ranges 2019-2026; Lincoln Herald, Lincoln Lore, JALA, Civil War History, Lincoln Forum; Burlingame/Emerson/Holzer/Williams responses; Semantic Scholar citation list for doi:10.1093/llc/fqy042 (41 citing works retrieved).

## 1. The study itself
Grieve, J., Clarke, I., Chiang, E., Gideon, H., Heini, A., Nini, A., Waibel, E., "Attributing the Bixby Letter using n-gram tracing," *Digital Scholarship in the Humanities* 34:3 (Sept. 2019), pp. 493-512, doi:10.1093/llc/fqy042; submitted 26 May 2017, accepted 1 Aug. 2018, online 26 Oct. 2018 (https://academic.oup.com/dsh/article-abstract/34/3/493/5145759). Preprint: https://pure-oai.bham.ac.uk/ws/files/53402456/Bixby_PREPRINT.pdf; conference version (Corpus Linguistics 2017, Birmingham): https://www.birmingham.ac.uk/Documents/college-artslaw/corpus/conference-archives/2017/general/paper200.pdf. Press coverage was in July 2017, before publication: *Time* (https://time.com/4855857/abraham-lincoln-john-hay-bixby-letter/), *Smithsonian* (https://www.smithsonianmag.com/smart-news/was-abe-lincolns-most-famous-letter-written-his-secretary-180964145/), *Newsweek* (https://www.newsweek.com/abraham-lincoln-bixby-letter-john-hay-jk-rowling-639788), AOL/Fox (21 July 2017). An Atlas Obscura piece (https://www.atlasobscura.com/articles/lincoln-bixby-letter-ngram-tracing) exists; its date could not be verified (403), and a search-engine summary's claim that it appeared on 7 Aug. 2025 is unconfirmed.

## 2. Replications, re-analyses or critiques of the Bixby attribution: none found
- No published re-analysis of the Bixby letter by any other stylometric method was found for 2019-2026.
- No published rebuttal by a Lincoln historian (Burlingame, Emerson, Holzer, Williams, Steers) directed at the 2019 study was found. The scholarly journals searched (JALA at scholarlypublishingcollective.org; *Lincoln Herald*; Project MUSE; JSTOR via search) returned nothing on Bixby after 2008 except the 1995 Burlingame article's new hosting page (https://scholarlypublishingcollective.org/uip/jala/article/16/1/59/394080/New-Light-on-the-Bixby-Letter).
- The Wikipedia article "Bixby letter" (my copy of the wikitext) cites nothing later than 2018; it reports the study ("identified Hay as the letter's author") alongside the Lincoln-side evidence without deciding.

## 3. Methodological literature that bears on n-gram tracing (not on Bixby specifically)
- Proisl, T., Evert, S., Jannidis, F., Schoech, C., Konle, L., Pielstroem, S., "Delta vs. N-Gram Tracing: Evaluating the Robustness of Authorship Attribution Methods," *Proceedings of LREC 2018* (Miyazaki), https://aclanthology.org/L18-1523/. Abstract (as given at https://cris.fau.de/publications/201093222/): "N-gram tracing is a novel method for authorship attribution designed for very short texts, which has its roots in forensic linguistics. We evaluate the performance of both methods in a series of experiments on English, French and German literary texts ... Our results show that, at least in our setting, both methods require relatively long texts and are furthermore highly sensitive to the choice of authors and texts in the comparison corpus." The paper cites Grieve et al. (2017) as the source of the method and does not discuss the Bixby letter (PDF fetched 14 Sept. 2026). Published before the DSH article but after the 2017 preprint; it is the only independent robustness test of the method that I found.
- Nini, A., *A Theory of Linguistic Individuality for Authorship Analysis* (Cambridge Elements in Forensic Linguistics, 2023) - by a co-author of the 2019 study; cites it; no indication from the abstract or reviews that it re-examines Bixby (https://www.cambridge.org/core/elements/abs/theory-of-linguistic-individuality-for-authorship-analysis/E52B7B8ADC2B5EC579037AC9D81575E5).
- Huang, W., Murakami, A., Grieve, J., "ALMs: Authorial Language Models for Authorship Attribution," arXiv:2401.12005 (v1 22 Jan. 2024, v2 13 Feb. 2024) and "Attributing authorship via the perplexity of authorial language models," *PLOS ONE* (3 July 2025), doi:10.1371/journal.pone.0327081 - Grieve's newer method; neither mentions the Bixby letter, Lincoln or Hay (both fetched 14 Sept. 2026).
- Applications of n-gram tracing to other corpora among the citing works: Manousakis, N., "Authorship Analysis and the Ending of Seven Against Thebes," *Classical World* (2023) and "Authorship Analysis and the Authenticity of Euripides' Electra 518-44," *Classical Philology* (2024); White, B. L., "Counting Paul" (2025); Nini, A., "idiolect: An R package for forensic authorship analysis," *JOSS* (2026); Barlow, S. E., "Normalisation-Based Likelihood Ratio Estimation for Forensic Authorship Verification," arXiv (2026). None re-tests Bixby (titles/venues from the Semantic Scholar citation list; contents not examined).

## 4. New popular/historical writing touching the question (2026)
- Jan Cigliano Hartman, *Lincoln's Speechwriter: John Hay and the Friendship That Inspired American Eloquence* (Post Hill Press, distributed by Simon & Schuster, 2026; ISBN 9798895652800; 382 pp.). It argues Hay had a large hand in Lincoln's speeches and letters. Two reviews:
  - Neil Hrab, "Lincoln's Ghost - and 'Private Wordsmith'?", *Pro Rhetoric* (Vital Speeches of the Day), dated 25 March 2026 on the page as fetched (a search snippet gives 16 April 2026), https://prorhetoric.com/lincolns-ghost-and-private-wordsmith/: "There is also the famous Bixby letter, which is believed by some to have been written by Hay, according to investigations by experts in the esoteric field of 'forensic linguistics.'" and "Perhaps further supportive evidence will come in the years ahead, as those masters of 'forensic linguistics' harness the proliferation of AI-related tools and extend their comparative Lincoln/Hay studies beyond the Bixby letter." The reviewer notes "the vast majority of Lincoln scholars have yet to be won over."
  - Harold Holzer, "Book Review: Lincoln's Speechwriter," *Emerging Civil War*, 23 July 2026, https://emergingcivilwar.com/2026/07/23/book-review-lincolns-speechwriter-john-hay-and-the-friendship-that-inspired-american-eloquence/: "Lincoln scholars have been debating for years about Hay's connection to one of the great works long universally attributed to Lincoln alone: his magisterial condolence letter to Lydia Bixby"; "Aside from its use of a few words unseen in other Lincoln writing, the principal argument for Hay's authorship is that Hay kept a copy of the letter in his scrapbook"; "The original has never been located. Some speculate that Bixby, a Democrat, tossed it into the fire - so we may never know its authorship for sure." Holzer rejects the book's wider ghost-writing thesis (surviving Lincoln drafts of the Gettysburg Address and Second Inaugural).
  The author's site (https://www.janciglianohartman.com/) does not mention the Bixby letter. I did not read the book; whether it adds any new document on Bixby is unknown.

## 5. Documentary discoveries since 2019
None found. The original manuscript remains lost; no new statement by Hay or by any contemporary has been reported. The Papers of Abraham Lincoln online search (my saved results page) lists no manuscript for the letter.

## 6. Summary
Between 2019 and September 2026 the only developments I could verify are (a) continued citation of the n-gram study as a methodological milestone, (b) one earlier robustness study of the method on other corpora (Proisl et al. 2018) that warns of sensitivity to corpus choice and text length, and (c) a 2026 trade book and two reviews in which the Bixby attribution is mentioned as "believed by some." No replication, refutation or new evidence on the Bixby letter itself was found. This is a statement about what the searches returned, not proof that nothing exists in venues that could not be reached (Project MUSE full text, JSTOR, HathiTrust, Google Books).