Question: What foundation do scholars give for the likelihood of collaboration on a William Shakespeare Play written between 1588 and 1593?

Passages:
Parivara (Pali for "accessory") is the third and last book of the Theravadin Vinaya Pitaka.  It includes a summary and multiple analyses of the various rules identified in the Vinaya Pitaka's first two books, the Suttavibhanga and the Khandhaka, primarily for didactic purposes.  As it includes a long list of teachers in Ceylon, even Theravada fundamentalists recognize that, at least in its present form, it is of late date.  Scholars give it a late date, some suggesting it may be even later than the Fourth Council in Ceylon in the last century BCE, at which the Pali Canon was written down from oral tradition. Love's Labour's Won is a lost play attributed by contemporaries to William Shakespeare, written before 1598 and published by 1603, though no copies are known to have survived.  Scholars dispute whether it is a true lost work, possibly a sequel to "Love's Labour's Lost", or an alternative title to a known Shakespeare play. <P1-S0> Titus Andronicus is a tragedy by William Shakespeare, believed to have been written between 1588 and 1593, probably in collaboration with George Peele. <P1-S1>  It is thought to be Shakespeare's first tragedy, and is often seen as his attempt to emulate the violent and bloody revenge plays of his contemporaries, which were extremely popular with audiences throughout the 16th century. The authorship of "Titus Andronicus" has been debated since the late 17th century. " Titus Andronicus", probably written between 1588 and 1593, appeared in three quarto editions from 1594 to 1601 with no named author.  It was first published under William Shakespeare's name in the 1623 First Folio of his plays.  However, as with some of his early and late plays, scholars have long surmised that Shakespeare might have collaborated with another playwright.  Other plays have also been examined for evidence of co-authorship, but none has been as closely scrutinised or as consistently questioned than "Titus".  The principal contender for the co-authorship is George Peele. Like most playwrights of his period, William Shakespeare did not always write alone.  A number of his surviving plays are collaborative, or were revised by others after their original composition, although the exact number is open to debate.  Some of the following attributions, such as "The Two Noble Kinsmen", have well-attested contemporary documentation; others, such as "Titus Andronicus", are dependent on linguistic analysis by modern scholars; recent work on computer analysis of textual style (word use, word and phrase patterns) has given reason to believe that parts of some of the plays ascribed to Shakespeare are actually by other writers. Although traditionally Titus Andronicus has been seen as one of Shakespeare's least respected plays, its fortunes have changed somewhat in the latter half of the twentieth century, with numerous scholars arguing that the play is more accomplished than has hitherto been allowed for.  In particular, scholars have argued that the play is far more thematically complex than has traditionally been thought, and features profound insights into Ancient Rome, Elizabethan society, and the human condition.  Such scholars tend to argue that these previously unacknowledged insights have only become apparent during the twentieth and twenty-first centuries as only now has the ultraviolent content of the play achieved a sense of relevance.  For example, in his 1987 edition of the play for the "Contemporary Shakespeare" series, A.L. Rowse writes; "in the civilised Victorian age the play could not be performed because it could not be believed.  Such is the horror of our own age, with the appalling barbarities of prison camps and resistance movements paralleling the torture and mutilation and feeding on human flesh of the play, that it has ceased to be improbable."  Similarly, director Julie Taymor, who staged a production Off-Broadway in 1994 and directed a film version in 1999, says she was drawn to the play because she found it to be the most "relevant of Shakespeare's plays for the modern era;" She feels that the play has more relevance for us than it had for the Victorians; "it seems like a play written for today, it reeks of now."  Because of this new found relevance, previously unrecognised thematic strands have thus come to the forefront. Revenge tragedy (less commonly referred to as revenge drama, revenge play, or tragedy of blood) defines a genre of plays made popular in early modern England.  Ashley H. Thorndike formally established this genre in his seminal 1902 article "The Relations of Hamlet to Contemporary Revenge Plays," which characterizes revenge tragedy "as a tragedy whose leading motive is revenge and whose main action deals with the progress of this revenge, leading to the death of the murderers and often the death of the avenger himself."  Thomas Kyd's "The Spanish Tragedy" (c.1580s) is often considered the inaugural revenge tragedy on the early modern stage.  However, more recent research extends early modern revenge tragedy to the 1560s with poet and classicist Jasper Heywood's translations of Seneca at Oxford University, including "Troas" (1559), "Thyestes" (1560), and "Hercules Furens" (1561).  Additionally, Thomases Norton and Sackville's play "Gorbuduc" (1561) is considered an early revenge tragedy (almost twenty years prior to "The Spanish Tragedy").  Other well-known revenge tragedies include William Shakespeare's "Hamlet" (c.1599-1602) and "Titus Andronicus" (c.1588-1593) and Thomas Middleton's "The Revenger's Tragedy" (c.1606). In music, the Romanian Minor scale or Ukrainian Dorian scale or altered Dorian scale is a musical scale or mode, "similar to the dorian mode, but with a tritone and variable sixth and seventh degrees".  It is related to both the Freygish and Misheberak scales and is used in Jewish music, "predominant in klezmer bulgarish and doina (doyne)."  "When the Ukrainian Dorian scale functions in the synagogue, it is a mode known as the "Mi sheberach" (May He Who Blessed) or "Av horachamim" (Compassionate Father).  Arab and Greek scholars give other names to the scale: "Hijaz" and "Aulos", respectively." The Philadelphia Shakespeare Festival is an annual Shakespearean theatre festival in Philadelphia.  Every year, The Festival produces two or three productions of Shakespeare's plays.  Starting out as the Red Heel Theatre in 1989, and changing name and purpose in 1993, The Philadelphia Shakespeare Festival is now the region’s only theatre devoted entirely to Shakespeare’s works.  In 2008/9, they engaged in intensive planning with the board of directors and cultural and community leaders and decided to re-brand and rename the company to better reflect their programming.  The Philadelphia Shakespeare Theatre now has several programs for adults and students including a lecture series featuring world-renowned Shakespeare scholars, Shakespeare School Tour which also tours in schools, and a Classical Acting Academy providing early career actors with intense classical training culminating in a free summer Shakespeare play for the public. <P3-S0> The Battle of Morella (14 August 1084×88), southwest of Tortosa, was fought between Sancho Ramírez, King of Aragon and Navarre, and Yusuf al-Mu'tamin, King of Zaragoza, while the former was engaged in a campaign of conquest against the latter. <P3-S1>  All surviving sources for the battle are either later by a generation or literary in character, and they are confused on the chronology and dating of the event. <P3-S2>  The encounter was a defeat for Sancho and sparked a brief reversal of fortunes in the Navarro-Aragonese "Reconquista". <P3-S3>  The Castilian hero, Rodrigo Díaz de Vivar, the Cid, was a general for al-Mu'tamin at the time. <P3-S4>  According to the Aragonese "Crónica de San Juan de la Peña" ("c".1370), Sancho later sought out the Cid, who had also defeated his father in the Battle of Graus (1063), and defeated him in the year 1088. <P3-S5>  However, the "Crónica" is the only source mentioning such an encounter and, as it was written three hundred years later, most leading scholars give no credence to this claim, which was probably intended to justify the prerogatives of Peter IV of the Crown of Aragon.

Supporting sentences:
Titus Andronicus", probably written between 1588 and 1593, appeared in three quarto editions from 1594 to 1601 with no named author.  Some of the following attributions, such as "The Two Noble Kinsmen", have well-attested contemporary documentation; others, such as "Titus Andronicus", are dependent on linguistic analysis by modern scholars; recent work on computer analysis of textual style (word use, word and phrase patterns) has given reason to believe that parts of some of the plays ascribed to Shakespeare are actually by other writers.