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Estimate Base Accuracies

This module analyses the traces at each base call to estimate a confidence value for the called base. It does this by simply looking at the area underneath the trace for the called base and dividing this by the highest area under the trace for the three uncalled bases. This is a very simplistic statistic which should ideally only be used for measuring the average reliability of the entire sequence rather than any individual base. If another program (eg Phred, or ATQA) is available then this should be used in preference. From the 2002 release the eba values are normalised to the phred scale (this was achieved by comaring the original eba values and phred values for 4.6 million base calls of Sanger Centre data). There are no adjustable parameters for this module.

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This page is maintained by staden-package. Last generated on 22 October 2002.