Version 2.5.18 of the SPOT software fixes sign errors in the
SPOT is set of tools for model-based optimization and tuning of algorithms (hyperparameter tuning or hyperparameter optimization). It includes surrogate models, optimizers, and design of experiment approaches. The main interface is spot, which uses sequentially updated surrogate models for the purpose of efficient optimization. The main goal is to ease the burden of objective function evaluations, when a single evaluation requires a significant amount of resources.
This version will be available on CRAN soon, see https://cran.r-project.org/package=SPOT. In the meantime, you can also download the package source code from https://www.spotseven.de/spot/