Do statistical anchors in the opening sentence increase AI citation?
Hypothesis
If the opening sentence contains a specific number ("cut latency 43%"), citation rate will be higher than a version with vague language ("improved latency significantly") for product-performance queries. LLMs weight precise, citable data points as credibility signals.
Setup
Engines: Gemini, ChatGPT, Perplexity, Claude. 32 trials per variant across 4 engines (8 per engine), below our pre-registered threshold of 30 per engine.
Result
21.9%
Variant A (vague) citation rate
50%
Variant B (specific number) citation rate
+62.5pp, p=0.007
Significant effect (Claude only)
The specific-number variant (B) was cited in 16 of 32 trials (50%) versus 7 of 32 (21.9%) for the vague variant (A). The only statistically significant per-engine effect was on Claude (+62.5pp, p=0.007), which was not the pre-registered primary platform. Gemini returned 8/8 null responses due to API failures (since fixed), so its data is missing entirely.
Why this verdict
Sample size (n=8 per variant per engine) is below the pre-registered n≥30; the significant effect appeared on Claude rather than the pre-registered primary platform (Perplexity); and Gemini data is missing due to API failures. Encouraging direction, but not yet a finding we will state as fact.
What we do next
Re-run at n≥30 per engine with the Gemini API fix in place, keeping Perplexity as the pre-registered primary platform. If the effect holds, it graduates to "supported" and we will say so plainly.