Conditional Mode

The conditional sig is a measure of the probability that a signal component in a target star occurs, although a coincident signal component is found in a comparison star or sky background. It provides an answer to the question, ``What is the probability that a signal component with given amplitude and sig in the target data is not due to the same process that produces a coincident signal component with given amplitude and sig in the comparison data?''

The conditional CINDERELLA mode is comparable to the differential sig (SIGSPEC manual, p.), although the numerical results are not the same.

• For the differential mode of SIGSPEC, the full spectral information is available. Thus SIGSPEC handles the DFT spectra as continuous functions. CINDERELLA accesses only a list of peaks detected by SIGSPEC. Deviations of corresponding peak frequencies in comparison and target spectra cannot be handled as accurately as in the case of differential sig computation.
• The differential mode of SIGSPEC compares power integrals over the entire frequency range under consideration for the transformation of amplitudes from comparison into target data. Since CINDERELLA deals with a list of frequencies rather than the entire spectra, different strategies to transform amplitudes have to be employed. See ``Amplitude transformation'', p..