Rolling Stylometry

intro to a sequential analysis of style

Maciej Eder

Polish Academy of Sciences | University of Tartu

Authorship attribution

Non-traditional authorship attribution

Given:

  • a text of uncertain or anonymous authorship, and
  • a comparison corpus of texts by known authors,

is it possible to find the ‘nearest neighbor’ among the available candidates?

Example: Prometheus Bound

  • Aeschylus known for his 7 tragedies
  • Prometheus Bound somewhat odd, and thus disputed
  • Traditional arguments against Aeschylus’ authorship
    • Zeus depicted as a cruel tyrant
    • slightly different versification patterns
    • the third actor needed in one of the scenes

Stylometry: where it (usually) begins

               καὶ     δ   γὰρ    δὲ     ὦ    ὡς   τὸν   ἀλλ    τὸ    ἐν
Aesch_Ag     1.734 2.784 0.965 0.989 0.122 0.647 0.550 0.232 0.843 0.867
Aesch_Eum    2.718 2.322 1.038 1.114 0.264 0.510 0.434 0.378 0.887 0.925
Aesch_Lib    2.128 2.477 1.028 1.156 0.550 0.587 0.404 0.422 0.514 0.991
Aesch_Pers   2.062 2.331 1.040 1.291 0.405 0.713 0.231 0.347 0.424 0.424
Aesch_Prom   1.857 1.536 1.097 1.232 0.236 0.557 0.557 0.422 0.591 0.405
Aesch_Septem 2.131 2.893 0.841 1.114 0.391 0.430 0.528 0.293 0.215 0.782
Aesch_Supp   2.206 2.712 0.648 1.012 0.223 0.607 0.304 0.324 0.688 0.587
Aristoph_Ach 2.151 1.305 0.694 0.680 1.166 0.597 1.069 1.096 0.944 0.486
Aristoph_Av  2.521 1.163 0.874 0.874 0.772 0.484 1.154 0.595 0.726 0.447
Aristoph_Ec  2.551 1.250 1.614 0.898 0.716 0.534 1.172 1.067 1.106 0.482
Aristoph_Eq  3.628 1.153 0.941 0.616 1.097 0.549 1.209 0.795 0.605 0.795
Aristoph_Nu  2.784 0.880 0.859 0.497 0.921 0.569 1.563 1.025 0.714 0.383
Aristoph_Pax 2.884 0.982 1.156 0.584 1.542 0.783 0.932 0.957 0.684 0.323
Aristoph_Pl  2.779 1.377 1.672 0.898 0.689 0.787 1.353 0.910 0.652 0.320
Aristoph_Ra  3.133 1.055 1.088 0.870 0.696 0.435 1.218 0.859 0.892 0.446
Aristoph_Th  2.420 1.031 1.031 0.839 1.114 0.591 0.811 0.660 0.990 0.399
Aristoph_V   2.605 0.814 1.058 0.722 0.845 0.743 1.170 0.997 0.753 0.468
Eur_Ba       1.366 2.194 0.814 1.327 0.617 0.828 0.683 0.433 0.657 0.998
Eur_El       1.381 2.294 1.108 1.329 0.782 0.626 0.313 0.469 0.169 0.834

Table of computed distances

             Aesch_Ag Aesch_Eum Aesch_Lib Aesch_Pers Aesch_Prom
Aesch_Ag       0.0000    0.8701    0.8453     0.9059     0.9737
Aesch_Eum      0.8701    0.0000    0.9311     0.9995     1.0242
Aesch_Lib      0.8453    0.9311    0.0000     0.9961     1.0411
Aesch_Pers     0.9059    0.9995    0.9961     0.0000     1.0034
Aesch_Prom     0.9737    1.0242    1.0411     1.0034     0.0000
Aesch_Septem   0.9166    0.9639    0.9832     0.9448     1.0334
Aesch_Supp     0.8546    0.9083    0.9764     0.9363     0.9707
Aristoph_Ach   1.0465    1.1672    1.1558     1.1025     1.0434
Aristoph_Av    1.1260    1.1974    1.2125     1.1292     1.0873
Aristoph_Ec    1.2108    1.2909    1.2650     1.2537     1.1270
Aristoph_Eq    1.1116    1.2165    1.1751     1.1301     1.0500
Aristoph_Nu    1.1055    1.2140    1.2050     1.1748     1.0558
Aristoph_Pax   1.1199    1.2549    1.2173     1.1512     1.0876
Aristoph_Pl    1.1999    1.2931    1.2948     1.2655     1.1674
Aristoph_Ra    1.0861    1.1780    1.1563     1.1452     1.0277
Aristoph_Th    1.1064    1.1974    1.1747     1.1770     1.1055
Aristoph_V     1.1080    1.2059    1.1916     1.1622     1.0544
Eur_Ba         0.9822    1.0982    1.0513     1.0231     1.0175
Eur_El         1.0146    1.1006    0.9912     1.1021     1.0855

Hierarchical cluster analysis

Multidimensional scaling

Bootstrap consensus tree

Rolling stylometry

Style in microscopic scale

Sequential analysis

Roman de la Rose

  • 13th-century French allegorical poem…
  • … of mixed authorship:
    • Guillaume de Lorris (ca. 1230)
    • Jean de Meun (ca. 1275)
  • The takeover point known (after the line 4,058).

Roman de la Rose

Queen Sophia’s Bible

  • 15th-century Polish translation of the Bible
  • Two volumes:
    • 2nd disintegrated early, before 17th cent.
    • 1st lost (destroyed?) during WWII
  • Fortunately, a 1930 facsimile exists

Queen Sophia’s Bible

Queen Sophia’s Bible

  • Translated from Czech
    • Hebrew → Latin → Czech → Polish
  • Five scribal hands recognizable
  • Probably more than one translator involved
  • Multi-level collaborative work

Queen Sophia’s Bible

Queen Sophia’s Bible

Harper Lee

  • 15 July 2015: Go Set a Watchman
    • second novel by Harper Lee
    • To Kill a Mockingbird (1960) got the Pulitzer
    • haevily edited by Tay Hohoff
  • Roumors that Truman Capote wrote it
  • Roumors that Lee wrote In Cold Blood

Truman Capote did write it

The Mockingbird

The Mockingbird

The Vugate (St. Jermome?)

The Vugate (St. Jermome?)

questions?