Methodology: How Our AI Signals Work
What we measure, how we measure it, where the data comes from, and where it stops being reliable. If a number appears anywhere on this site, this page explains how it was produced.
How does Stock Companion score news sentiment?
Every headline for a ticker is scored by two models. VADER is a lexical scorer that maps financial vocabulary to a compound polarity between -1 and +1 and runs in milliseconds. FinBERT is a transformer trained on financial phrasebanks that reads whole sentences, so it correctly classifies phrasing where individual words mislead — "the company cut its debt" is bullish despite the word "cut". The score shown on a ticker page is the mean across the headlines analysed in the trailing window.
How is a buy, hold or sell signal generated?
The signal is a multi-factor score, not a sentiment reading alone. It combines the aggregate news sentiment, the density of coverage over the window, and the recent price action, and it only classifies a direction when sentiment and price momentum converge. Divergent inputs — bullish sentiment against a falling price, for example — resolve to HOLD rather than a directional call, because divergence is usually noise or hype.
Where does the market data come from?
Quotes and historical prices come from Finnhub, Financial Modeling Prep, Polygon and EODHD, queried through a failover aggregator so a single provider outage does not blank a page. News headlines come from Finnhub. Insider transactions come from SEC Form 4 filings, institutional positions from 13F filings, and congressional trades from STOCK Act disclosures.
How often does the data refresh?
Ticker pages serve a cached snapshot that refreshes every 15 minutes; each page states the timestamp it was generated. Insider, institutional and congressional filings appear as the source agencies publish them, which for some filing types is on a statutory delay of days to weeks.
Are the backtest results on the homepage real trading returns?
No. The comparison figures shown on the landing page are illustrative simulations of the strategy against a buy-and-hold benchmark, not audited results and not the returns of any real account. Backtests benefit from hindsight, exclude slippage and most trading costs, and cannot account for the market conditions that will actually apply going forward. Past performance does not guarantee future results.
Is any of this financial advice?
No. Stock Companion is a research and monitoring tool. Nothing on the site is a personal recommendation, none of it accounts for your circumstances or risk tolerance, and no signal should be traded without your own analysis. We are not a registered investment adviser or broker-dealer.
Corrections and editorial policy
Automated articles are labelled as such and are generated from the same market data and sentiment pipeline described above. If you find a factual error in anything we publish, email [email protected] and we will correct or withdraw the page.
Risk disclaimer
Trading equities involves substantial risk of loss and is not suitable for every investor. Signals, sentiment scores and backtested figures are informational only and are not a recommendation to buy or sell any security. Past performance does not guarantee future results. You are solely responsible for your own trading decisions.
Questions about a specific metric? See the glossary or contact support.