Hi Matteo,
AFAIK in statistical analysis zero means the value was determined no signal was
detected, while a missing value means the value is unknown because no data is
available.
When analyzing mass spectrometry data in MZmine, the data is always available,
therefore we export all missing values as zeroes.
Occasionally, some peaks may be misaligned and therefore erroneously reported
as undetected. Use the gap filling function to fix that.
Best regards,
Tomas
On Jun 7, 2012, at 11:16 PM, Matteo Stocchero S-IN wrote:
Dear MZmine support,
I am Matteo from Italy and I am focused on multivariate data analysis.
I am working with data sets produced by MZmine2 and I have an important
question about the zeros in the peak list.
I used RANSAC aligner in order to reduce the number of zeros.
However, a large number of zeros appears in the data set.
I do not understand if the zeros have to be considered missing values or values
equal to zero.
In statistical analysis this implies a different treatment of the data.
Could you please clarify me this point?
Thank you in advance.
Best regards.
Matteo
--
Matteo Stocchero, PhD
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