[R] Validation data critically small with GSIF

I'm trying to make spatial prediction of rainfall erosivity (data from 23 Rainfall gauges) with GSIF package (RK method). I got this error message (and no prediction): Error in validObject(.Object) : invalid class SpatialPredictions object: Validation data critically small (50) for reliable

Re: [R] Validation data critically small with GSIF

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