Table 1.

The data sets considered in this work (except for the NIST 17 database).

Designation	N	Compounds	Stationary Phase	Reference a
FLAVORS	1169	Flavors and fragrances	Carbowax 20 M	[26,27]
ESSOILS	427	Essential oils components	Various polar SP	[4,25]
DB-624	545 b	Various aliphatic and aromatic alcohols, esters, ethers, aldehydes, sulfur-containing compounds, heterocycles, nitriles and other compounds	DB-624	[11]
OV-17	192	Odorants (the Flavornet database https://www.flavornet.org/, accessed on 22 August 2021)	OV-17	[24]
BPX50_2D	859 c	The diverse set of environmental-related compounds: pesticides, organophosphates, esters, polyaromatic compounds, polychlorinated biphenyl congeners, polychlorinated dioxins, bisphenols, etc.	BPX50	[28]
SEDB624	130	Series of homologues of ketones, aldehydes, alcohols, alkylbenzenes, alkenes, chloroalkenes, cycloalkenes, esters, and other compounds	DB-624	[31]
DB-1701	36	Flavors and fragrances	DB-1701	[32]
DB-210	130	The same compounds as in the SEDB624 data set	DB-210	[31]

^a—both the original source and the actually used secondary source are specified, when applicable. The number N of data records actually used in this work is given. ^b—the data set is split into the training and test sets in the original work (396 and 149 data entries, respectively). ^c—the data set is split into the training, test, and external test sets in the original work (359, 168, and 332 data entries, respectively).