Does only “The Oz” himself know who wrote The Royal Book of Oz? Who Wrote the 15th Book of Oz? An Application of Multivariate Analysis to Authorship Attribution José Nilo G. Binongo sisting of 14 books. He consequently earned the title, “The Royal Historian of Oz.” Nye describes the scenario in the early 1900s: The Wizard was apparently writ- ten with no intention of supply- ing a sequel; it is a complete unit, with nothing in it to anticipate a successor, much less thirteen of them. … [Baum did try] to end the series in 1910 with The Emerald City of Oz, but he was driven back to Oz by the demands of his readers... Finally, promising that “as long as you care to read them I shall try to write them,” he resigned himself to at least one Oz story Who is the author of The Royal Book of Oz? each year. (Gardner and Nye, p. 5) The Royal Even in frail health, Baum tried hard Historians of Oz it became a children’s best seller by to keep that promise. Carpenter and Christmas of 1900. Such an instant Shirley (1992, p. 117) write the details: Lyman Frank Baum (1856–1919), success led biographer Russell Mac- according to Martin Gardner, was Fall to write a chapter about 1900, call- In 1918, Frank agreed to have his “America’s greatest writer of children’s ing it Baum’s annus mirabilis (Baum gallbladder removed. By this time fantasy.” “His Wonderful Wizard of Oz and MacFall 1961). he had written two extra Oz has long been the nation’s best known, After writing the first Oz book, books, The Magic of Oz and best loved native fairy tale” (Gardner Baum could not separate himself from Glinda of Oz . They were to and Nye 1957, p. 19). Although ini- the fantasy land he created. In less than be published if he became too ill tially rejected by publishers in Chicago, two decades, he produced a series con- to write a new book each year. CHANCE 9 . [After his surgery, he] tried to The Royal Book of Oz The story about Baum’s unfinished adjust to his new way of life by notes seems to have been fabricated by writing a little each day. Propped The 15th book in the series is now the publishers in an effort to ease the up on pillows, he finished The Tin believed by many to be Thompson’s transition and, presumably, to guaran- Woodman of Oz for a 1918 publi- first work. Moore (1974, p. 89) reports: tee sales. With the Del Rey edition in cation date. 1985, Thompson was identified as the Notes and a fragmentary draft author of the book. Following her name of . The Royal Book of Oz were on the title page was the qualification, Unfortunately, Baum’s condition presumably turned over by his “Founded on and continuing the took a turn for the worse. On May 5, publisher to a successor, Ruth famous Oz stories by L. Frank Baum.” 1919, he suffered a stroke. “Baum’s Plumly Thompson, but no one In 2001, a Dover edition of the book generous heart, unlike the fine velvet seems to know exactly how was released. As noted by the publisher, heart of the Tin Woodman, was not much of this book was really this is “an unabridged republication of Baum’s work. replaceable” (Gardner and Nye, p. 40). the [1921] work.” As such, this edition He passed away the next day. His last The complication started in 1921, credits Baum as the author on the front words were: “Now we can cross the the year the 15th book was published. and back cover. However, the explana- Shifting Sands” (Baum and MacFall, Baum’s name was on the cover, and tion on the back cover is not very clear: p. 275). Thompson was acknowledged only as Interpreting a conversation between having “enlarged and edited” the work. The Royal Book of Oz Ozma and Dorothy in Baum’s last book, L. Frank Baum Riley (1997) opines that “if Baum had Before his death, L. Frank Baum, been able to write more stories, there the “Royal Historian of Oz,” left would have been more plots involving behind notes for more delightful Ozma settling disputes and extending stories about the adventures of her benevolent rule to all the undis- Dorothy and her friends in Oz. covered corners of Oz” (pp. 222–223). This charming sequel, based on With Baum’s death, the publishers those notes and written by Ruth Reilly & Lee (formerly Reilly & Britton) Plumly Thompson, fully captures had to find someone to continue writ- the excitement, imaginative ing tales about Ozma’s reign. The spirit, and playfulness of Baum’s motive appeared to be commercial: own work. nineteen years after the publication of Although Baum’s name follows the title the first book, the series was still very of the book, Thompson is acknowl- popular and profitable. Reilly & Lee edged as having written the work. negotiated a compromise with the Can statistics help shed light on the widow Maud Baum, promising “a fixed authorship of the 15th book? That is, royalty for her and Baum’s heirs on is it possible to show statistically that every Oz book, no matter who was the Title page of Oz sequel written by the writing style in the 15th book is, author” (Baum and MacFall, p. 277). Thompson indeed, more like Thompson’s than Ruth Plumly Thompson (1891– Baum’s? Critics like Riley (1997) claim 1976), an established children’s writer, In her letter after the title page, Mrs. that “[Thompson’s] writing style was took on the job as Baum’s successor. Baum explained that the book was quite different from Baum’s” (p. 233). Although 35 years younger than Baum, based on “some unfinished notes” her Can we actually show using statistical Thompson started her career at 23, husband had left. Three decades later, tools that each author used a consis- when she wrote a page for children Oz chronicler Jack Snow (1954) wrote tently distinct style when narrating an every week in the Philadelphia Public that the 15th book was, in reality, Oz story? Ledger. Reilly & Lee were not disap- Thompson’s own work. The current pointed: Thompson, like her predeces- predominant view sides with Snow. Hearn (2000, p. lxxxv), for example, sor, was a prolific writer. Every A Non-Traditional asserts that Christmas season from 1921 to 1939, Method of Attributing readers enjoyed a new Oz adventure by Thompson did not base the story Authorship Thompson. According to Riley (1997, on any notes Baum left behind p. 232), for many American children of as stated in the introduction. The Albeit described by humanities schol- the time, Oz and Santa Claus were twin Royal Book of Oz was entirely her ars as “non-traditional,” the use of images of Christmas. The classic own work. Thompson did not quantitative techniques to resolve the MGM movie with Judy Garland was slavishly imitate what Baum had authorship of a disputed text has been released in 1939. By that year, Thomp- done, but instead built on his around for more than a century. son had published the 33rd Oz book. creation. Binongo and Smith (1996) traced one 10 VOL. 16, NO. 2, 2003 of the first uses of the word “stylome- try” in the work of Wincenty Lutoslawski (1897). Calling his method “stylometric,” Lutoslawski attempted a computational procedure to establish a relative chronology of Plato’s dialogues. Reflecting on his approach, he wrote: this . new science of style . will enable us to decide ques- tions of authenticity and chronol- ogy of literary works. This future science of stylometry may improve our methods beyond the limits of imagination. (p. 193) Figure 1. Why function words? Lutoslawski’s words proved prophetic. Progress in stylometry has been made possible through technolog- ical advancement. Even the early work of Mosteller and Wallace on the author- ship of “The Federalist Papers” relied on technology that was available in the 1960s. With the proliferation of elec- tronic texts on the Internet and in libraries all over the globe, some researchers have considered looking at literary style from a quantitative view- point. In the present investigation, we dif- ferentiate between literary styles using a graphical approach. In particular, we will demonstrate graphically that the works of Baum and Thompson are dia- metrically different, even as they write about the same fairy land. The same Figure 2. Finding 50 variables to describe each text. tool is then used to decide which of the two Historians of Oz is more likely to have written the 15th book. While it is ter recognition software. Proofreading reprinting of all of Thompson’s books true that stylometric methods do not both the downloaded and scanned by the Books of Wonder should allow rely on subjective impressions, quan- texts was at once the most time-con- the inclusion of the missing works in a tification does not always produce suming and the most enjoyable part of future study. results that can be trusted. Thus, prior the study, as it provided the opportu- A computer program was then writ- to the attribution proper, it is important nity to reread the timeless tales. The ten to count the number of occurrences to check the reliability of the proposed texts were edited in that whenever an of each of the words used. Of these method using works known to have author (particularly Baum) altered the words, function words of the highest been written by either author. spelling of a character’s words to sug- frequency were selected.