Momentum and mean-reversion are opposite bets - and most strategies quietly assume one is true. Quantora measures which regime a stock actually lives in using the Hurst exponent and the Lo-MacKinlay variance-ratio test, so you know before you trade whether trend-following or fading has an edge here.
The Hurst exponent H is estimated from how return variance scales with horizon (aggregated-variance method): H near 0.5 is a random walk, H above 0.5 is persistent/trending, H below 0.5 is anti-persistent/mean-reverting. The variance ratio VR(q) compares q-day return variance to q times 1-day variance (Lo-MacKinlay, homoskedastic z-statistic); above 1 signals trending, below 1 signals reversion. Based on daily log returns over roughly five years. Educational only - not investment advice.