Rhea-AI 8: Impact Scores 13% More Accurate on the Same News
Rhea-AI 8 is the new version of StockTitan’s news impact engine, released in September 2026. It changes what the Impact score measures, which is now the move a stock makes after the news, pre-market and after-hours included, and when we scored the same September 2026 news with both engines it landed on the exact impact level 13% more often than the engine it replaces. It also missed 70% fewer big moves, which are the cases where the news was rated Low or Neutral and the stock then jumped or dropped 10% or more.
Key Numbers at a Glance
What the Impact score measures now
Every article on StockTitan carries a Rhea-AI Impact score from 1 to 5, and the question behind it has always been how much a piece of news can move a stock. With version 8 we made the answer match what you see on a chart once the news is out. Impact now measures the largest move from the last trade before publication to the close of the trading session that reacts to it, so earnings released after the close get credit for the gap they cause the next morning, and a biotech that jumps 40% in the pre-market counts even if half of it is gone by the close.
The earlier score looked at the whole trading day, which meant a stock that had already swung before a 3 p.m. press release could make that release look important when it was not, and moves outside regular hours were missed. The levels read the same way as before, from Low under 2% to Very High at 20% or more, and the score still does not care about direction, since a failed trial and a buyout offer are both Very High news.
How much better Rhea-AI 8 is
We scored the same 6,945 news articles from September 2026 with both engines, news that neither engine’s development had used, and compared every score with the move that followed. Rhea-AI 8 put the news on exactly the right level 13% more often, and scores that missed by two levels or more became 26% rarer.
The gains are largest where they matter most to a trader. Think of the news that was followed by a move of 10% or more, up or down. The old engine rated some of it Low or Neutral, which means a trader who trusted the score would have skipped it, and Rhea-AI 8 makes that mistake 70% less often. It also rated 11% more of those big moves High or Very High, and when it did give a High or Very High score, the stock went on to move 10% or more 15% more often than with the old engine. Earnings reports that moved the stock 10% or more were rated High or Very High 38% more often than before.
It also judges each company more fairly. One weakness of the old engine was that some companies seemed to get the same score for everything they published, and across July and August 2026 the number of companies whose news all received the same level fell by 63%.
How often a top score is followed by a big move
The question most traders ask of any score is whether a Very High rating really comes before a big move. On the September news, 402 of the 487 articles Rhea-AI 8 rated Impact 5 were followed by a move of 10% or more, up or down, which is more than 8 in 10, and 254 of them, more than half, were followed by a move of 20% or more. Of the news the previous engine rated Impact 5, 73% reached a 10% move, and across all of that September news only 17% of articles did, so an Impact 5 from Rhea-AI 8 made a big move almost 5 times as likely as an average article.
The score holds up at the other end of the scale too. Of the 1,362 articles Rhea-AI 8 rated Impact 1, only 2 were followed by a move of 10% or more, against 21 of 1,117 with the previous engine, so when Rhea-AI 8 rates a piece of news Low, a big move afterwards is rare.
What you will see in your feed
Because the score now counts pre-market and after-hours moves, you will see more High and Very High scores on busy earnings days, and far fewer big moves hiding behind a Low or Neutral score. Scoring still happens within milliseconds of publication, before most readers have finished the headline, and the full definition, calibration tables and limitations are on the Rhea-AI methodology page.
What comes next
Rhea-AI 8 is one step in a longer run of work. We keep testing new ideas against the market’s own record, and we keep improving every part of StockTitan, from the speed of the news feed to the tools you use around it, so expect more updates like this one.
Frequently Asked Questions
What is Rhea-AI?
Rhea-AI is StockTitan’s proprietary news analysis engine. It scores every press release and SEC filing on StockTitan, about 50,000 documents a month, with an Impact score for the likely size of the stock’s move and a Sentiment score for the tone of the language.
What does the Rhea-AI Impact score measure in version 8?
It estimates the largest move a stock makes after the news, up or down, from the last trade before publication to the close of the trading session that reacts to it, with pre-market and after-hours trading included. Level 1 means under 2% and level 5 means 20% or more.
How much more accurate is Rhea-AI 8?
On the same 6,945 news articles from September 2026, it matched the exact impact level 13% more often than the previous engine and missed 70% fewer big moves, the news it rated Low or Neutral that was then followed by a move of 10% or more.
Data Sources
The information provided in this article is for educational and informational purposes only. It does not constitute financial advice, investment recommendation, or an endorsement of any particular investment strategy. Past performance does not guarantee future results. Investors should conduct their own research and consult with a qualified financial advisor before making investment decisions.