The report was based on an analysis of the top 10 results for desktop Google.com searches in the US for 4,000 keywords. The researchers examined how different search factors are correlated with high rank across eight topic areas: cars, furniture, credit, financial planning, weight loss, recipes, destinations, and camping.
Google's expanded use of machine-learning and AI to hone results appears to be increasingly resulting in different types of pages rising to the top in different topic areas, the analysis found.
For example, top ranking furniture-related pages have 28 images, on average, whereas credit-related pages have only seven images, on average.
Top-ranking pages related to weight loss are much more likely to include video content compared with top-ranking pages in the other topic areas examined.
The average word count of top-ranking pages related to financial planning is more than triple the average word count of top-ranking pages related to camping (2,500 vs. 700).
About the research: The report was based on an analysis of the top 10 results for desktop Google.com searches in the US for 4,000 keywords.