Trajectory and Model (IMAGE) National Institutes of Natural Sciences Caption Fig. 1. (A) Trajectory of single-molecule motion and corresponding chemical-state-dependent free energy profiles. (B) Schematic of a hidden Markov model in which the chemical states are regarded as "hidden" states. Credit NINS/IMS Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.