In this paper we examine numerically the subcritical flutter characteristics of wings in a supersonic flow. Especially the scattering property of the criterion parameters which are used in order to estimate a flutter boundary, is studied. The wing response due to the flow turbulence is expressed by the autoregressive moving-average process through Akaike's estimation procedure. The wing stability is evaluated by applying the Jury's stability determinant method for a discrete system to the estimated time series model. The flutter boundary is predicted by plotting the Jury's stability criterion parameter at several dynamic pressures in the subcritical range. As the dynamic pressure approaches to the flutter boundary, the estimated stability parameter and its scattering monotonically decreases while the damping, the conventional flutter estimation criterion, scattered so much near the flutter boundary.