[...]
If you can persuade the people measuring the values to give you the numbers (assuming they are just below `limit of detection' rather than genuine non-detects) you will reduce the need for imputation.
This is often the most powerful technique -- analytical chemists are
trained not to give out numbers less than some multiple of the
measurement error, but they can often be persuaded that statisticians
can be trusted with these numbers.
[...]
Dear Thomas and dear R people,
thank you very much for these words. Similar discussions are frequently observed with people of the "applied side". I repeatedly point out, that scientific data should include also values lower than the "measurement limit", but in most cases they do are not willing, sometimes because of legal reasons and in other cases simply, because someone told them, that this is would be an unsound behaviour. Are there citable references, I can use as antidote?
Thomas P.
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