On truncated spectral regularization for an ill-posed evolution equation

We consider the spectral truncation as the regularization for an ill-posed non-homogeneous parabolic final value problem, and obtain error estimates under a general source condition when the data, which consist of the non-homogeneous term as well as the final value, are noisy. The resulting error estimate is compared with the corresponding estimate under the Lavrentieve method, and showed that the truncation method has no index of saturation.