Fig. 6
![Fig. 6](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs13007-019-0422-z/MediaObjects/13007_2019_422_Fig6_HTML.png)
The fourth step of the Bayesian optimization procedure with \(\kappa =2\). Left: optimized function (solid green line), observed points (blue dots), GPR predictive mean (dashed red line) and standard deviation intervals (orange fill). Right: UCB acquisition function at the current step with star depicting the next guess, which is close to the true maximum