Table 2.

List of the features used in the predictive modeling. Note that a “cutoff” represents the time when a customer calls in the case of “positive samples” (when there is an actual complaint), or the time drawn at random in the case of “negative samples” (see Methods).

Feature name	Definition
MostRecentConcentration	Assay concentration reading just before cutoff
TwoMostRecentConcentrationMean	Mean concentration for the two readings before cutoff
FiveMostRecentConcentrationMean	Mean concentration for the five readings before cutoff
TenMostRecentConcentrationMean	Mean concentration for the ten readings before cutoff
TwoMostRecentConcentrationSD	SD of concentration for the two readings before cutoff
FiveMostRecentConcentrationSD	SD of concentration for the five readings before cutoff
TenMostRecentConcentrationSD	SD of concentration for the ten readings before cutoff
NbPriorSGenChange	Number of S Gen changes before cutoff (since start of QC sample)
NbPriorSLotChange	Number of S Lot changes before cutoff
NbPriorERFLotChange	Number of ERF Lot changes before cutoff
NbPriorIWFLotChange	Number of IWF Lot changes before cutoff
NbPriorContLotNumChange	Number of Control Lot Number changes before cutoff
NbPriorCalCurveChange	Number of Calibration Curve changes before cutoff
TimeSinceLastSGenChange	Time elapsed since last S Gen change before cutoff
TimeSinceLastSLotChange	Time elapsed since last S Lot change before cutoff
TimeSinceLastERFLotChange	Time elapsed since last ERF Lot change before cutoff
TimeSinceLastIWFLotChange	Time elapsed since last IWF Lot change before cutoff
TimeSinceLastContLotNumChange	Time elapsed since last Control Lot Number change before cutoff
TimeSinceLastCalCurveChange	Time elapsed since last Calibration Curve change before cutoff
TimeToComplain	Time elapsed since last e-Connectivity log before cutoff