I have added spectral radius scaling of reservoir matrix to desired value $\rho$ along $\sigma$ and $\tau$ parameters in W $\sim$ N(0, $\sigma^2$ ) and $W^{in}$ $\sim$ Unif(- $\tau$ , $\tau$ ) to the exploration. $100$ neuron reservoir was used and $100$ instances for every pair ( $\tau$ , $\sigma$ ) were generated.

The Z values are mean NRMSE from 100 instances.

NARMA

NARMA without unscaled

Mackey – Glass

Mackey-Glass unscaled

Lorenz

Lorenz unscaled

Minimum achieved mean:
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