We present a novel methodology to estimate the uncertainty in ensemble particle image velocimetry (PIV). Ensemble PIV is widely used to improve the cross-correlation SNR. Despite the utility of ensemble PIV, there is no method for quantifying the uncertainty in velocity measurement using ensemble PIV. Here we propose a method to find the uncertainty from the PDF of displacements. The PDF is found using the image-based Probability Estimation of Displacement (iPED) approach that we previously developed, published, and made the codes publically available. We then find the second moment of the PDF, apply a normalization factor, and report uncertainty in velocity measurement. We term this method as the Moment of Probability of Displacement (MPD).
