  Context. To identify the real associations of small bodies, we can use
synthetic sets of orbits generated by various methods. These are not perfect
methods, therefore the assessment of their quality is an essential task. Aims.
In this study, we compared five methods for generating synthetic meteoroid
orbits. Three of them (ME0, KD10, and KDns) had already been proposed in the
literature, while two additional ones (ME1 and ME4) are new methods. Methods.
As far as possible, the synthetic orbits were compared with the orbits of the
observed meteoroids. For quantitative comparison, we applied a few tests: the
chi-square distance and the nearest neighbor NN_N tests used in previous works,
and one-dimensional chi-square and Kolmogorov-Smirnov (K-S) tests, as well as a
two-dimensional K-S test implemented in this study. To estimate a general
property of the orbital sample, we proposed the use of the entropy H_N of the
data set based on the nearest neighbor distances. Finally, we did a cluster
analysis of the synthetic orbits. We calculated and compared the values of the
orbital similarity thresholds. Results. We showed that generating 'realistic'
meteoroid orbits and testing their quality is a complex issue. An assessment of
the quality of the generated orbits depends on the type of test applied, and it
refers to the sample of the observed orbits used. Different tests give
different assessments. However, in practice, the investigated methods produced
similar results if they were applied correspondingly.
