Abbreviations	Description
1H NMR	proton nuclear magnetic resonance
2D	two-dimensional
3D	three-dimensional
Am-241	americium-241
ANN	artificial neural networks
ANOVA	one-way analysis of variance
APPI	atmospheric pressure photo ionization
Bias	systematic error
CC	capillary column
CCS	collision cross section
CD	corona discharge
Ctr	mean centering
CV	cross validation
D(I)MS	differential ion mobility spectrometry
DHS	dynamic headspace extraction
DTIMS	drift-tube ion mobility spectrometry
E-nose	electric nose
EVOO	extra-virgin olive oil
FAIMS	high-field asymmetric waveform ion mobility spectrometry
ft	film thickness
FT-IR	Fourier-transform infrared spectroscopy
GC	gas chromatography
GC–IMS	gas chromatography-ion mobility spectrometry
H+[H2O]n	proton-water clusters with n number of water molecules
H-3	tritium
HCA	hierarchical cluster analysis
HOG	histograms of oriented gradients
HS	headspace
ID	inner diameter
IMS	ion mobility spectrometry
K0	reduced ion mobility
KMO	Kaiser–Meyer–Olkin
kNN	k-nearest neighbors
L(V)OO	lampante (virgin) olive oil
LC	liquid chromatography
LDA	linear discriminant analysis
LDI	laser desorption/ionization technique
LOO	leave-one-out
LS	library search
M2H+	proton-bound dimers
MCC	multicapillary column
MCR-ALS	multivariate curve resolution alternating least squares
MH+	protonated monomers
MPCA	multiway principal component analysis
MVA	multivariate variate data analysis
Ni-63	nickel-63
NTS	non-targeted screening
OPLS-DA	orthogonal partial least-squares discriminant analysis
Par	Pareto
PC(A)	principal component (analysis)
PLS(R)	partial least squares (regression)
POO	pomace olive oil
(Q)DA	(quadratic) discriminant analysis
R²	determination coefficient
RE	relative error of prediction
Regressor	logistic regression
RIP	reactant ion peak
RMSE	root mean square error
RS	reference substances
(R)-SVM	(recursive) support vector machine
SEP	standard error of prediction
SHS	static headspace extraction
SIMCA	soft independent modeling of class analogy
SPME	solid-phase microextraction
TIMS	trapped ion mobility spectrometry
Tree	decision tree classification
TWIMS	travelling tube ion mobility spectrometry
UnVa	unit variance
UR	univariate regression
UV	ultraviolet light
VIP	variable importance in projection
VOC	volatile organic compound
(V)OO	(virgin) olive oil