Search engines in polarized media environment: Auditing political information curation on Google and Bing prior to 2024 US elections (2501.04763v1)

Abstract: Search engines play an important role in the context of modern elections. By curating information in response to user queries, search engines influence how individuals are informed about election-related developments and perceive the media environment in which elections take place. It has particular implications for (perceived) polarization, especially if search engines' curation results in a skewed treatment of information sources based on their political leaning. Until now, however, it is unclear whether such a partisan gap emerges through information curation on search engines and what user- and system-side factors affect it. To address this shortcoming, we audit the two largest Western search engines, Google and Bing, prior to the 2024 US presidential elections and examine how these search engines' organic search results and additional interface elements represent election-related information depending on the queries' slant, user location, and time when the search was conducted. Our findings indicate that both search engines tend to prioritize left-leaning media sources, with the exact scope of search results' ideological slant varying between Democrat- and Republican-focused queries. We also observe limited effects of location- and time-based factors on organic search results, whereas results for additional interface elements were more volatile over time and specific US states. Together, our observations highlight that search engines' information curation actively mirrors the partisan divides present in the US media environments and has the potential to contribute to (perceived) polarization within these environments.

• The paper finds that both Google and Bing tend to prioritize left-leaning media sources in political search results, contributing to perceived biases.
• User-side factors such as the ideological slant of queries significantly influence results, with Democratic queries yielding more left sources and Republican queries increasing right sources.
• System-side factors like location have minimal impact on political slant, while time-based changes show more influence, especially in Google's Newsblock.

Evaluation of Political Information Curation by Google and Bing Prior to the 2024 US Elections

This paper examines the political information curation of Google and Bing during the 2024 U.S. Presidential elections through a comprehensive algorithm audit. Focusing on user- and system-side factors, the paper evaluates how search engine outputs are influenced by the ideological slant of queries, search localization, and time-based changes in source relevance.

Summary of Results

The audit reveals several notable findings:

1. Ideological Bias in Search Results: Both Google and Bing show a tendency to prioritize left-leaning media sources irrespective of query type. This contributes to perceived biases, supporting accusations of skewed political representation by search engines, particularly in favor of left-leaning media outlets.
2. User-Side Influences: The ideological slant of the queries plays a significant role in results' output. Democratic-focused queries yield a higher representation of left-leaning sources, while Republican-focused queries increase the presence of right-leaning news sources.
3. System-Side Factors: The influence of location and timing was examined to understand regional and temporal variation in search outputs. Interestingly, the results suggest minimal impact of search localization on the political slant, while time-based fluctuations are more pronounced, especially in Google's Newsblock output.

Implications and Future Research Directions

These observations convey significant implications for both search engine accountability and potential societal polarization:

• Potential for Contributing to Polarization: By mirroring partisan divides prevalent in media environments, search engines may exacerbate perceived polarization among users.
• Normative Role of Search Engines: The paper prompts a discussion on the role of search engines as information curators. Should they act as neutral reflectors of media landscapes or actively curate to ensure exposure to diverse perspectives? The answer remains crucial in the context of modern democratic societies.

This paper opens multiple avenues for future investigation, including expanding the diversity of query selections and analyzing content-specific biases in search outputs. Additionally, further exploration of non-media source bias could provide a more comprehensive understanding of information curation practices.

While the findings are instructive, the limitations related to query representation and geographic scope necessitate an expanded methodological approach in future research to capture a fuller picture of search engines' political information curation. These expansions could strengthen the political accountability of search engines and improve democratic information diffusion.