Generative search engines often draw from lesser-known sources, new research reveals.
A recent study published by researchers at Ruhr University in Germany and the Max Planck Institute for Software Systems found that generative search engines rely on less popular websites and ones that wouldn't appear in Google's top 100 links. This was discovered after a comparison of traditional link results from Google to its AI Overviews and Gemini-2.5-Flash, as well as other AI-powered tools.
The study involved analyzing test queries, including specific questions submitted to ChatGPT in the WildChat dataset, general political topics listed on AllSides, and products included in the 100 most-searched Amazon products list. The researchers also compared these results to traditional Google links for the same query.
According to the findings, AI search engines cited sources that were less popular than those appearing in traditional Google links. Specifically, Gemini showed a tendency to cite unpopular domains, with the median source falling outside of Google's top 1,000. In some cases, more than half of the sources cited by Google's AI Overviews didn't appear in the top 10 Google links for the same query.
While these findings raise questions about the accuracy and reliability of AI search results, they also suggest that generative engines can be a valuable resource when searching for less common information. For instance, GPT-based searches were more likely to cite corporate entities and encyclopedias, while almost never citing social media websites.
However, the reliance on pre-trained data can become a limitation when searching for timely information. In some cases, AI-powered search engines responded with generic messages rather than actual web results.
The study concludes that future research is needed to develop new evaluation methods that consider source diversity, conceptual coverage, and synthesis behavior in generative search systems.
A recent study published by researchers at Ruhr University in Germany and the Max Planck Institute for Software Systems found that generative search engines rely on less popular websites and ones that wouldn't appear in Google's top 100 links. This was discovered after a comparison of traditional link results from Google to its AI Overviews and Gemini-2.5-Flash, as well as other AI-powered tools.
The study involved analyzing test queries, including specific questions submitted to ChatGPT in the WildChat dataset, general political topics listed on AllSides, and products included in the 100 most-searched Amazon products list. The researchers also compared these results to traditional Google links for the same query.
According to the findings, AI search engines cited sources that were less popular than those appearing in traditional Google links. Specifically, Gemini showed a tendency to cite unpopular domains, with the median source falling outside of Google's top 1,000. In some cases, more than half of the sources cited by Google's AI Overviews didn't appear in the top 10 Google links for the same query.
While these findings raise questions about the accuracy and reliability of AI search results, they also suggest that generative engines can be a valuable resource when searching for less common information. For instance, GPT-based searches were more likely to cite corporate entities and encyclopedias, while almost never citing social media websites.
However, the reliance on pre-trained data can become a limitation when searching for timely information. In some cases, AI-powered search engines responded with generic messages rather than actual web results.
The study concludes that future research is needed to develop new evaluation methods that consider source diversity, conceptual coverage, and synthesis behavior in generative search systems.