An arbitrary static threshold might be set to divide "warm" from "hot".
No on/off switches where passing some arbitrary threshold of needs gets support but being 5% short of it gets nothing.
A second problem with the absent/present calls is that they are based on essentially arbitrary thresholds, with no simple estimate of the risk of false positives or false negatives.
These arbitrary, and fairly lax, thresholds were used because they proved to give reasonable numbers of genes in each partition.
BLASTN matches with an arbitrary threshold expect value ( E -value) of less than 0.01 were investigated as significant matches.
The C t scores represent the cycle number at which fluorescence signal (ΔR n ) crosses an arbitrary (user-defined) threshold.
This arbitrary threshold was chosen to exclude genes whose fluorescence intensity was close to background fluorescence.
The reason computers can be used to compute is that voltages above an arbitrary threshold have been deemed by the designer to represent the digit one.
The most common strategy for interpreting Affymetrix microarray data is to use two profile comparisons, with an arbitrary threshold for "significant fold-change" in expression levels.
What falls at this arbitrary threshold?