Table 1 Comparison of a standard deviation (SD) and signal to noise (S/N) ratio for a raw CN signal obtained using different types of references. Here SD is an average of all SDs obtained for each raw CN segmented region in log2 scale, and S/N is computed as a ratio of the difference between the raw CN values corresponding to CN = 3 and CN = 2 in log2 scale and the SD value defined above

From: A novel SNP analysis method to detect copy number alterations with an unbiased reference signal directly from tumor samples