Increasingly often, presentations are given before a live audience, while simultaneously being viewed remotely and recorded for subsequent viewing on-demand over the Web. How should video presentations be designed for web access? How is video accessed and used online? Does optimal design for live and on-demand audiences conflict? We examined detailed behavior patterns of more than 9000 on-demand users of a large corpus of professionally prepared presentations. We find that as many people access these talks on-demand as attend live. Online access patterns differ markedly from live attendance. People watch less overall and skip to different parts of a talk. Speakers designing presentations for viewing on-demand should emphasize key points early in the talk and early within each slide, use slide titles that reveal the talk structure and are meaningful outside the flow of the talk. In some cases the recommendations conflict with optimal design for live audiences. The results also provide guidance in developing tools for on-demand multimedia authoring and use.

Note: OCR errors may be found in this Reference List extracted from the full text article. ACM has opted to expose the complete List rather than only correct and linked references.

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