Visible Comments Had the Edge

A comment's vote ranking within its thread showed the largest association in the selection model. A one-standard-deviation increase multiplied the odds of being chosen by 2.88.

The median selected comment sat at the 91st percentile for score in its thread, versus the 45th percentile for comments not chosen. Of the selected comments, 92% were direct replies to the original post, which accounted for 53% of all comments. Selected comments appeared a median of 1.2 hours after the post went up; non-selected comments appeared after a median of 5.9 hours.

Length mattered too. A one-standard-deviation increase in comment length carried an odds ratio of 1.79, and comments containing an external link had an odds ratio of 2.25.

Comments scoring zero or below made up 0.53% of selected comments but 5.1% of all comments collected.

The Written Answer Dropped Most First-Person Language

In an analysis of 1,000 queries, the researchers compared Reddit's quoted comments with the responses crafted around them. Usage of words like "I" and "my" fell from 3.3% in the quoted comments to 0.06% in the answers.

The same queries went through GPT-4o-mini and GPT-5 via OpenAI's API with web search enabled. Both models used less first-person language than Reddit comments, but Reddit's responses showed the largest reduction.

Across 4,932 citations, only 18 referenced Reddit across both models and search configurations. This data is based on API calls for advice queries, which differs from the setup in the ChatGPT app.

How the Audit Worked

The researchers used an LLM to rewrite real posts from the 20 subreddits into short search queries. Ten are large communities such as r/personalfinance and r/AskDocs; ten are smaller ones such as r/UKJobs and r/AusLegal.

The three runs were spaced roughly five hours apart, so differences would reflect the system rather than changes on Reddit. When two runs pulled from the same source posts, the responses were almost identical — evidence that most variation came from which posts the system chose to retrieve.

A typical answer drew on about seven different subreddits. The subreddit where the question originated contributed 17.7% of retrieved posts in the large-community set and 15.7% in the small-community set. The authors note they don't consider a higher share better.

The paper refers to the feature as Reddit Answers, its name at launch in December 2024. Reddit's announcement page now shows an update from May 26, 2026: "Reddit Answers is now merged into Reddit search for one unified search experience." The questions were created from posts dated through July 2026, so the runs happened after that change, though the paper doesn't specify collection dates. Reddit's Help page now describes the feature as AI search, accessible through an Ask button in the search bar.

Why This Matters for Marketers

Reddit's value for audience research lies in people describing their own experience with a product or a problem. In these 20 communities, comments with more markers of that experience were less likely to reach the AI answer — and most of the first-person wording disappeared when they did.

Reddit CEO Steve Huffman told investors in February that Reddit is particularly good at questions where "the answer actually is multiple perspectives from lots of people." This audit measured which of those perspectives actually reached the AI answer.

The source threads are listed beneath each answer. Read them before including any summary in a report.

The authors caution that these selection patterns may not carry over to other kinds of communities or to other AI search systems. The findings may change if a revised or peer-reviewed version emerges.