However, it would be useful if these methods could also detect when all samples are highly biased, indicating that few representative samples from the equilibrium distribution have been obtained and more sampling is required. In other words, it would be useful if truncation point selection heuristics could be used for equilibration detection. In the context of MSER, truncation times over 50 % of the simulation time have been taken to indicate a lack of equilibration. We tested this heuristic by applying all generalised MSER methods to the first 0.2 ns of the "standard" synthetic datasets (Figure and Table ). For all time series, the optimal fixed-time truncation points were at over 50 % of the total time, and usually close to 100 %. PDE2a had large and quickly decaying bias at these short timescales (Table ), which produced a steep decrease of RMSE with increasing truncation time compared to all other systems. For all other systems, the distributions of discard times were relatively narrow and centred at less than 0.05 ns for all methods. Hence, all methods failed to detect insufficient sampling according to the 50 % time rule. However, for PDE2a, the size 50