A normalisation method for oligonucleotide arrays motivated by spatial biases
نویسندگان
چکیده
Many oligonucleotide arrays contain spatial flaws. Standardisation methods such as quantile scaling make no reference to the spatial nature of the flaws. However, the spatial compactness of such flaws can be exploited to provide the basis for corrections that are quite independent of any subsequent chip-wide correction procedure (such as quantile scaling). With three or more replicate arrays, visualisation of defects is a simple matter. With Lklr denoting the logarithm of the signal intensity at location (k, l) in array r, an effective procedure involves calculating and plotting the values of dklr given by:
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