We prescribe the minimal set of experimental data and parameters that should
be reported for random-laser experiments and models. This prescript allows for
a quantitative comparison between different experiments, and for a criterion
whether a model predicts the outcome of an experiment correctly. In none of
more than 150 papers on random lasers that we found these requirements were
fulfilled. We have nevertheless been able to analyze a number of published
experimental results and recent experiments of our own. Using our method we
determined that the most intriguing property of the random laser (spikes) is in
fact remarkably similar for different random lasers.Comment: 3 pages, 1 figur