A method for detecting targets, comprising:
- a) receiving spectral data;
- b) using a normal compositional model for estimating background parameters from said spectral data and target components;
- c) estimating abundance values of classes of said normal compositional model from said background parameters and said spectral data;
- d) estimating target class covariance values from said spectral data, said background parameters, and said target components;
- e) estimating target-plus-background abundance values from said target class covariance values, said background parameters, said spectral data, and said target components;
- f) employing a normal compositional model for determining a likelihood ratio detection statistic from said target class covariance values, said target-plus-background abundance values, said spectral data, said target components, said background parameters, and background abundance values;
- and
- g) generating a determination output signal that represents whether an observation includes a target from said likelihood ratio detection statistic.