Table 1.

A comprehensive summary of the reviewed predictors for Kcr site prediction

Tool	Algorithm	Species	Encoding scheme	Evaluation strategy	URL/stand-alone package	Histone or nonhistone	Benchmark dataset	Option of batch prediction	Window size	Published year	Reference
Qiu et al.	SVM	Human Mouse	PWAA	Jackknife test	No	Histone	101 Histone proteins, 169 positive, 847 negative	No	31	2017	[13]
CKSAAP CrotSite	SVM	Human Mouse	CKSAAP PseAAC	Jackknife test	123.206.31.171/ CKSAAP CrotSite/(not available)	Histone	101 Histone proteins, 169 positive, 847 negative	No	31	2017	[15]
iKcr-PseEns	Ensemble RF	Human Mouse	PseAAC	Jackknife test	http://www.jci-bioinfo.cn/iKcr-PseEns (available)	Histone	55 histones, 169 positive 46 Histones, 866 negative	Yes	35	2018	[16]
LightGBM-CroSite	LightGBM	Human Mouse	BE PWAA EBGW kNN PsePSSM	Jackknife test	https://github.com/QUST-AIBBDRC/LightGBM-CroSite/	Histone	101 Histone proteins, 159 positive, 847 negative	No	31	2020	[39]
iCrotoK-PseAAC	ANN	Mixed	PseAAC RPRIM PRIM SM SVV FV AAPIV RAAPIV	10-fold cross-validation	No	Mixed	378 Positive, 500 negative	No	41	2019	[14]
Deep-Kcr	CNN RF LB NB LR	Human	CKSAAP PWAA AAindex CTD EBGW	10-fold cross-validation	http://lin-group.cn/server/Deep-Kcr (available)	Mixed	3734 Proteins, 9964 positive, 9964 negative	No	31	2020	[17]

Abbreviations: EBGW, encoding based on grouped weight; kNN, k nearest neighbors, PsePSSM, pseudo-position specific scoring matrix; CTD, composition, transition and distribution; RPRIM, position relative incidence matrix; SVV, site vicinity vector; FV, frequency vector; AAPIV, accumulative absolute position incidence vector; RAAPIV, reverse accumulative absolute position incidence vector; NB, naïve Bayes; LB, logitboost.