Disentangling speaker and channel effects in speaker verification

We show how a joint factor analysis of inter-speaker and intra-speaker variability in a training database which contains multiple recordings for each speaker can be used to construct likelihood ratio statistics for speaker verification which take account of intra-speaker variation and channel variation in a principled way. We report the results of experiments on the NIST 2001 cellular one speaker detection task carried out by applying this type of factor analysis to Switchboard Cellular Part I. The evaluation data for this task is contained in Switchboard Cellular Part I so these results cannot be taken at face value but they indicate that the factor analysis model can perform extremely well if it is perfectly estimated.