Schanbacher (SSRN 2025): FAQPage and Product schema strongly predict ChatGPT visibility (single-domain peer-reviewed)

Claim: Schanbacher (SSRN paper id 5641050) studied 1,508 German real-estate agent websites and found:

• FAQPage schema: odds ratio ~13 for ChatGPT visibility (p<0.001)
• Product schema: odds ratio ~4 (p<0.001) — sites with Product schema had 17.2% visibility vs 1.8% without (~10× lift)
• Mobile-friendly: OR ~5.2
• robots.txt present: OR ~3.4
• Multi-level headings: h2 OR ~3.3, h3 OR ~2.3

Source: Schanbacher, "The Impact of JSON-LD Metadata on ChatGPT Visibility," SSRN paper id 5641050.

Confidence: Verified (peer-reviewed) — but single domain (real estate) and single country (Germany). Generalizability across industries/languages is unverified.

Contrasts with: Ahrefs (April 2026): adding schema to 1,885 pages produced no AI-citation lift; AI Overviews showed -4.6% (no lift on already-indexed pages). The reconciliation: Ahrefs measured increment on pages already cited 100+ times; Schanbacher measures acquisition on a population where many pages have zero AI visibility. Both findings can be true.