With three changes to form, not content: consistent heading hierarchy, information split into lists and tables instead of long paragraphs, and the direct answer at the start of each section instead of the end. A University of Tokyo study measured that reorganizing just that — without changing a single word of the content — raises citation rate by up to 17.3% across six AI engines.
Of the 39 Argentine e-commerce sites Nostos analyzed in its sector study, 62% score below 30 out of 100 in content structure. It's the worst-performing criterion in the whole sector — worse than authority, worse than technical markup, worse than data density. And it's the only one of Nostos's eight criteria that doesn't depend on what you say, but on how you arrange it.
The Tokyo paper proposes a framework (GEO-SFE) that splits content structure into three levels, and Nostos evaluates all three:
No AI engine "reads" a site the way a person does. A language model processes the document looking for these three levels of organization before deciding what to cite.
What makes this study methodologically solid is that it isolated the variable: it kept the semantic content intact — same data, same facts — and only changed how it was organized. The paper itself frames this as a formal constraint on its optimization: that the structural transformation preserve the semantic integrity of the original content.
The result, measured across six commercial generative engines: 17.3% more citations and an 18.5% improvement in perceived quality of the responses that incorporated that content.
In Nostos's study of 39 leading Argentine e-commerce domains, content structure was the sector's weakest criterion: 62% of the sites analyzed scored below 30 out of 100. It isn't a problem of how good the information on those sites is — many have correct, up-to-date data. It's that the information lives in long paragraphs, with no clear heading hierarchy, no lists or tables a model could chunk and cite piece by piece.
Translated into practice, the Tokyo study's three levels come down to this:
In yesterday's analysis (08/14/2026), Nostos measured 74/100 in Content Structure: the homepage has a clear, semantically coherent H1/H2 hierarchy — a precise H1 identifying the business's category, followed by H2s that segment the content by functional block.
Applying this article's same three criteria across the rest of the site, not just the homepage, there's still room to improve: consistent hierarchy on every page, not just the main one, and more use of lists and tables on product pages.
Get your GEO score across the eight criteria backed by academic research, including your current Content Structure.
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