Here's a detailed mathematical explanation of SIn: https://doi.org/10.1038/nbt.1592
Briefly, the normalization process produces fractional representation of quantities, i.e. 0.01, 0.052, etc. These are then log-transformed, which results in values that typically range from -5 to -30, but are always negative because they are log-transforms of values less than 1. These negative values can be adjusted by applying a scalar to the values (such as +30) so that all values are greater than 0. Alternatively, there is an option in StPeter (-s) where you can specify a total protein amount loaded into the instrument and StPeter will scale all the quantities to that amount. Note that this isn't an absolute value for each protein, because StPeter is standardizing the results to the sum of all *observed *proteins (not the ones you didn't identify), but it still puts all values in an easy to conceptualize, and positive, scale. These standardized numbers are comparable across samples (to obtain ratios) so long as the samples were acquired with the same instrument method and chromatography conditions. Cheers, Mike On Wednesday, August 16, 2023 at 10:53:34 AM UTC-7 sudarshan kumar wrote: > and > in StPeter what does negative SIn scor emean? I see all of them being > negative > -- You received this message because you are subscribed to the Google Groups "spctools-discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/spctools-discuss/8f61ecb0-ac2e-49d3-bf6f-bca2592b8a80n%40googlegroups.com.
