It matters how you google it? Using agent-based testing to assess the impact of user choices in search queries and algorithmic personalization on political Google Search results

Search engines, as key sources of political information, have sparked concerns regarding selective exposure driven by user choices based on political beliefs and filter bubbles created by algorithms. This study focuses on the most influential yet often-overlooked user choice: search queries. We investigate the extent to which user choices (search queries) and algorithmic personalization (search history) lead to divergent search results. Building on research linking immigration- and climate-related search queries to political characteristics, we conduct an experiment on Google Search employing agent-based testing. Using computational methods, we examine variations in search results by source (type) and search result page features. Our findings show that it is the specific search queries made by users, not algorithmic personalization, that lead to substantially divergent information sources in search results. This suggests future research should prioritize user choices in information search rather than control for them.