Comparison with other methods

Comparison with LOWESS (summary)

(assumed stable/definable character of data)
Calculation Data reproducibility
LOWESS Relationship between ratio and signal intensity (non-linear method)
→ not universal, but only unique to the pair of data
Alteration of the ratio with arbitrary functions
→ will make distortions, lead to the loss of objectivity
SuperNORM Statistical data distribution (parametric method)
universally found
Three parameter lognormal model based on the universal character
→ No distortion, ensuring objectivity

Conceptual diagram of LOWESS

Comparison with LOWESS (reproducibility in ratio determination)

LOWESS sometimes gives stable logratios that are not signal intensity dependent. However, the reproducibility in ratio determination is poor.

SuperNORM not only gives stable logratios, but finds out and cancels noise-affected data ranges. With noise-affected ranges determined, false-positive data could be identified. Data in the model-consistent range (dots in black) show high reproducibility in ratio determination.

Comparison with other methods

SuperNORM can be applied to dChip data which could be generated with PM-MM or PM only. In terms of reproducibility in ratio determination, SuperNORM will give better results than dChip.