For each gene at each time point we added values sampled from a Gaussian distribution centered on zero with a standard deviation calculated based on replicate measurements.
The reported accuracy (based on known AER), precision (based on replicate measurements), and limits of the PFT-derived AER measurements for occupied homes is estimated to be 20−25%, 5−15%, and 0.2−5.0 h−1, respectively (10, 21− 21−.
Subsequently, an error model based on replicate measurements was defined in Gene Spring, and the significance of differential expression was established using analysis of variance and the false-discovery rate method of Benjamini and Hochberg [ 49] to correct for multiple testing.
Interbatch coefficients of variation ranged between 2% and 8% based on 24 replicated measurements of plasma samples at a mean concentration (picograms per gram wet) range of 3.6 (cis-nonachlor) to 688 (p,p′-DDE).
This software uses an error model based on replicate Affymetrix chip measurements to determine the true error bounds and p-values and was therefore was an ideal choice for this type of analysis.
Long-term external reproducibility of δMo measurements is based on replicate processing and multiple analyses of two sediment reference materials SDO-1 and New Albany Shale, which have δMo = +0.88 ± 0.19‰, 2σ, n = 54, and +0.31 ± 0.20‰, 2σ, n = 27, respectively.
Based on replicate analyses of international and laboratory standards, measurement errors are less than ±0.2‰ for δC and δN.
Based on replicate analyses of international and laboratory standards, measurement errors are less than ±0.2‰ for δN.
Based on replicate analyses of international and laboratory standards, measurement errors were ≤0.2‰ for δC and δN for 92% of the study population (n = 1,178) and ≤0.9‰ for the remaining 8%.
Considering that evaluated platforms not only use different technology for gene expression measurements but also different protocols for preparation of samples prior to final quantification, we chose to calculate precision based on biological replicate measurements where replicates for each stimulation was prepared individually for analysis according to protocols for a certain platform.
