TexTile: A Pixel-Based Focus+Context Tool For Analyzing Variants Across Multiple Text Scales.

Before the advent of printed texts, text duplication was done primarily by hand. Errors, alterations, and erasures were common and varied widely across different copies of the same text. Classics scholars seek to reconstruct an "original" text by analyzing and merging variations across copies as "witnesses" to a conjectured original. Many scholars continue to use spreadsheets, sometimes as large sheets of actual paper, to visually collate variations across known versions. These approaches are generally well suited for collection of data about variations, a process that can take decades. However, they are poorly suited for analysis of variation above the level of individual words. Visualization techniques are needed to reveal patterns of variation at the level of lines, pages, and entire texts. We present TexTile, a new tool that integrates pixel-based and focus+context visualization techniques for analysis of reconstructed classical Latin texts. TexTile provides a comprehensive yet compact representation of variation at multiple levels over an entire text. The tool helps scholars validate the accuracy of textual variants and analyze similarities between different contributing copies. The integrated visualization design allows exploration of variation across textual scales while preserving continuity of browsing, much like when examining a physical manuscript. We conducted a mixed quantitative-qualitative user study to assess the usability of the integrated design.