check_date,study,publisher,published,url,design,sample,engines,variable_tested,key_finding,c1_when,c2_how_many,c3_where,c4_how_in_full,c5_raw_data,checks_passed,note
2026-10-30,AI brand visibility correlations,Ahrefs,2025-12-12 (updated 2026-08-12),https://ahrefs.com/blog/ai-brand-visibility-correlations,Spearman correlation,"75,000 brands","ChatGPT, AI Mode, AI Overviews","DR, backlinks, branded web mentions, branded anchors, branded search","Branded web mentions 0.656-0.709; DR 0.266-0.326; backlinks described as very weak",no,yes,no,no,no,1,Method described in part
2026-10-30,AI Overview brand correlation,Ahrefs,2025-05-26 (updated 2026-04-27),https://ahrefs.com/blog/ai-overview-brand-correlation/,Spearman correlation,"75,000 brands (DR>40)",AI Overviews,"Branded mentions, anchors, search, DR, referring domains, backlinks, UR","Branded web mentions 0.664; referring domains 0.295; backlinks 0.218",no,yes,no,no,no,1,About 26% of brands had zero mentions and were dropped
2026-10-30,Branded web mentions and AI visibility,Ahrefs,2025-07-07,https://ahrefs.com/blog/branded-web-mentions-visibility-ai-search/,Spearman correlation,"Top 50 domains per engine","AI Overviews, ChatGPT, Perplexity",Branded web mentions,"AIO 0.65, ChatGPT 0.15, Perplexity 0.30",yes,yes,no,no,no,2,No link variables tested
2026-10-30,Backlinks and AI search,Semrush with Growth Memo,2025-10-16,https://www.semrush.com/blog/backlinks-ai-search-study,Pearson and Spearman correlation,"1,000 domains","ChatGPT, ChatGPT search, Gemini, AI Overviews, Perplexity","Authority Score, follow and nofollow links","Authority Score vs mentions 0.57 (Spearman); follow 0.504 vs nofollow 0.509",no,yes,no,no,no,1,
2026-10-30,What if the best GEO strategy is the one you stopped investing in,Seer Interactive,2026-03-30,https://www.seerinteractive.com/insights/what-if-the-best-geo-strategy-is-the-one-you-stopped-investing-in,Spearman with false-discovery correction,"62 brands, 4 industries",ChatGPT (via Scrunch),37 DataForSEO metrics,"Domain authority 0.750 average; total backlinks 0.687; referring domains 0.685",no,yes,no,yes,no,2,Author flags brand size as likely confounder
2026-10-30,What drives brand mentions in AI answers,Seer Interactive,2025-01-07,https://www.seerinteractive.com/insights/what-drives-brand-mentions-in-ai-answers,Correlation (method not named),"10,000 questions",GPT-4o API,"Google rank, Bing rank, backlinks","Google page-one rank about 0.65; backlinks weak or neutral",no,yes,no,no,no,1,
2026-10-30,Does ranking predict AI citations,Rankability,2026-09-23,https://www.rankability.com/data/does-ranking-predict-ai-citations/,Descriptive,"1,645 query-page observations, 31 topics",11 AI engines,"Page referring domains, DR, rank","72.8% of cited pages had zero page-level referring domains; about 1 in 4 from DR below 40",yes,yes,no,no,no,2,Aggregate CSVs published; no raw citation set
2026-10-30,Brand prominence,Growth Memo,2026-05-04,https://library.growth-memo.com/p/brand-prominence,Correlation,"7,000 LLM citations matched to 75,000 brands",Chatbots (not itemised),Branded search demand,r about 0.33,no,yes,no,no,no,1,Backlinks discussed qualitatively only
2026-10-30,76% of AI Overview citations from the top 10,Ahrefs,2025-07-21,https://ahrefs.com/blog/search-rankings-ai-citations/,Descriptive,"1.9M citations from about 1M AIOs",AI Overviews,Organic rank,76.10% from top 10; median position 3,no,yes,no,no,no,1,Text and chart disagree on one median
2026-10-30,AI Overview citations and the top 10 (update),Ahrefs,2026-03-02,https://ahrefs.com/blog/ai-overview-citations-top-10/,Descriptive,"863k SERPs, 4M AIO URLs",AI Overviews,Organic rank,37.9% from top 10 (all SERP blocks),no,yes,no,no,no,1,Parsing method changed from July 2025 study
2026-10-30,AI search overlap,Ahrefs,2025-08-11,https://ahrefs.com/blog/ai-search-overlap/,Descriptive,"15,000 long-tail queries","ChatGPT, Gemini, Copilot, Perplexity",Google and Bing top 10,About 12% overlap with Google top 10 on average,yes,yes,no,no,no,2,
2026-10-30,AI Mode comparison study,Semrush,2025-07-21,https://www.semrush.com/blog/ai-mode-comparison-study/,Descriptive,"5,000 keywords, 150k+ citations","Perplexity, AI Overviews, AI Mode, ChatGPT",Google top 10,AI Mode about 54% domain / 35% URL overlap,no,yes,no,no,no,1,Country implied US but not stated
2026-10-30,Rank overlap after 16 months of AIO,BrightEdge,2025-09-18,https://www.brightedge.com/resources/weekly-ai-search-insights/rank-overlap-after-16-months-of-aio,Descriptive,Not stated,AI Overviews,Organic rank,Overlap 32.3% to 54.5%,yes,no,no,no,no,1,Page gives two different September 2024 figures
2026-10-30,87% of SearchGPT citations match Bing,Seer Interactive,2025-02-06,https://www.seerinteractive.com/insights/87-percent-of-searchgpt-citations-match-bings-top-results,Descriptive,"500+ citations, about 100 questions",ChatGPT search,Bing and Google rank,87%+ match Bing top results; 56% match Google,no,yes,no,yes,no,2,Authors call results directional
2026-10-30,Comparative analysis of web search and generative AI,Chen et al. (University of Toronto),EDBT/ICDT 2026,https://arxiv.org/html/2601.16858v2,Descriptive,"1,000 ranking queries","GPT-4o, Gemini 2.5 Flash, Claude 4.5 Sonnet, Perplexity Sonar Pro",Google top 10 domains,Mean Jaccard overlap 4.0% to 15.2%,no,yes,no,yes,no,2,
2026-10-30,Source coverage and citation bias in LLM-based vs traditional search,Zhang et al.,2025-12-10,https://www.arxiv.org/pdf/2512.09483,Classifier (XGBoost/SHAP),"55,936 US trending queries",Six LLM search engines vs Google and Bing,Domain popularity and page features,38% of domains appear in both; popularity top feature,yes,yes,yes,yes,no,4,Data offered for research use on request