Nat. Biotechnol. 21, 818–821 (2003)

In the legend to Figure 1 on page 819, text in parts b and c was transposed. The legend should have read as follows: (b) Weight factors. (c) Nearest-neighbor stacking energy. These stacking energies weakly correlated (r = 0.6) with that found in aqueous solution8, and are smaller in magnitude.

In the legend to Figure 2 on page 820, figure parts were referred to incorrectly. The legend should have read as follows: Accuracy test. Known concentrations of 14 'spike-in' genes are compared with those obtained from (a) PDNN, (b) MAS5.0 and (c) dChip. Each line represents a gene in 14 samples. The microarray raw data were obtained from the '1532 series' human data (see Methods for URL). For genes other than the 'spike-ins', standard deviations (s.d.) versus the averages of the log-transformed expression levels are shown in d, e and f as determined using PDNN, MAS5.0 and dChip7, respectively. Each of these figures contains 12,474 genes; top half shown in red.