Fig. 5

SHapley Additive eXplanation (SHAP) values of the top 10 most important features in the prediction of, respectively, the crop N (a,d), P₂O₅ (b,e) and K₂O (c,f) application rates using Histogram-based Gradient Boosted regression. (a–c) The top plots present the average feature importance, determined by the mean absolute SHAP value of each feature. (d–f) The bottom plots depict a SHAP value for each prediction and show the local feature importance and the feature effect. The color of a dot represents the value of the feature in that instance - red indicating relatively high, blue indicating relatively low values. A dot with a high SHAP value for a feature suggests a positive contribution to the prediction, whereas a negative SHAP value leads to a lower prediction. The features are ranked in order of descending average importance and the blue, green and orange squares indicate whether the feature is an environmental, agrological or socioeconomic characteristic.