Supplemental Material Accessible Visualization via Natural Language Descriptions: A Four-Level Model of Semantic Content Alan Lundgard and Arvind Satyanarayan IEEE Transactions on Visualization and Computer Graphics (TVCG), Special Issue on the 2021 Visualization Conference (VIS) corpus_sentences_labeled.json: Our corpus, consisting of all visualization descriptions (582 total) and labeled sentences (2,147 total), organized as follows. - vis id number: A unique four-digit id number. - descriptions: A list of each author id and the description they wrote for a given visualization. - sentences: A list of each sentence in the description, labeled according to our four-level model of semantic content. corpus_summary_and_evaluation.pdf: A typeset document containing the following. - Corpus Summary - Corpus descriptive statistics. - Corpus fingerprint visualization. - Evaluation Design - Examples of the rank-choice interfaces. - All questions shown in the rank-choice evaluation. - Evaluation Questionnaire - Demographic questions. - Visualization questions. /evaluation: A folder containing data and code from the rank-choice evaluation. - calculate_stats.py: Code for calculating the statistics reported in the paper. - blind_rankings_numeric.csv: Rank-choice data from blind readers, in numerical form. - blind_rankings_text.csv: Rank-choice data from blind readers, textual form. - sighted_rankings_numeric.csv: Rank-choice data from sighted readers, in numerical form. - sighted_rankings_text.csv: Rank-choice data from sighted readers, in textual form. /visualizations: A folder containing the visualizations (50 total) used for gathering the corpus, each file named according to the following. - vis id number: A unique four-digit number. - chart type: Bar, line, or scatter. - difficulty: Easy, medium, or hard. - topic: Academic, business, or journalism.