Long short-term memory for a model-free estimation of macronutrient ion concentrations of root-zone in closed-loop soilless cultures

Table 2 The average test accuracy of the six macronutrients (R²) for long short-term memory (LSTM) using a combination of hyperparameters

Number of perceptrons	Time step	Interval	Dropout probability	Learning rate	R²
8	168	1 h	1.0	0.001	0.58
64	168	1 h	1.0	0.02	0.64
128	1008	10 min	0.9	0.045	0.66
256	144	10 min	0.9	0.045	0.52
512	12	1 h	0.9	0.001	0.61
512	108	1 h	0.9	0.001	0.62
512	168	1 h	0.5	0.001	0.43
512	168	1 h	0.9	0.03	0.67
512	168	1 h	0.9	0.001	0.66
512	168	1 h	1.0	0.03	0.65
512	336	30 min	0.9	0.03	0.44
512	336	1 h	0.9	0.03	0.66
1024	168	1 h	0.9	0.03	0.60

ISSN: 1746-4811