We thank Sergey Fomel, Ryan Swindeman, Jitao Ma, Mauricio Sacchi, Karl Schleicher, and Josef Paffenholz for helpful discussions. We also thank three anonymous reviewers for constructive suggestions that help make the manuscript better. This paper and all the figures are prepared with the Madagascar software package, which is an open-source research environment for reproducible computational experiments (Fomel et al., 2013). Thus, we are grateful for its developers for providing such convenience.
2015-11-23