A system and a computer-implemented method for evaluating uncertainty of a predicted trajectory infrastructure is disclosed The method comprises collecting a plurality of data sets from a predicted trajectory: comprising providing an aircraft intent description based on the predicted trajectory; selecting both a point in time and one or more variables among the collected plurality of data sets as sources of uncertainty; representing each selected variable at the selected point in time as a uni-variable polynomial expansion; representing each non-selected variable by a single point; and combining selected and non-selected variables into a multi-variable polynomial chaos expansion representing a stochastic prediction of the aircraft's trajectory at the selected point in time and a measurement of a sensitivity of the prediction to each of the selected one or more sources of uncertainty.