How are emotional arcs computed from text in Reagan et al. 2016, what do they not measure, and what do critics say?

Reagan et al. (arXiv 1606.07772v3) build emotional arcs for 1,327 Project Gutenberg books by sliding 10,000-word windows scored with the labMT word list (Hedonometer) and decomposing them with SVD and clustering; they note dictionary methods do worse than random on single sentences and say the arc measures the emotional trajectory of the syuzhet, not the plot (fabula). Curator qualifications: 10,000-word windows make the method unsuitable for scene-level analysis of short scripts (producer synthesis; not tested). van Cranenburgh secondary abstract (S19) and arXiv licence link (S21, CC BY-NC-SA 4.0 per producer) not reinspected. Text only; notebook code not run. Limitations: Preprint version v3. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

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      "url": "https://arxiv.org/pdf/1606.07772",
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      "url": "https://research.rug.nl/nl/publications/annotation-and-prediction-of-movie-sentiment-arcs/",
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