  We present a comparative study of two self-assembled quantum dot (QD) systems
based on II-VI compounds: CdTe/ZnTe and CdSe/ZnSe. Using magneto-optical
techniques we investigated a large population of individual QDs. The systematic
photoluminescence studies of emission lines related to the recombination of
neutral exciton X, biexciton XX, and singly charged excitons (X$^+$, X$^-$)
allowed us to determine average parameters describing CdTe QDs (CdSe QDs): X-XX
transition energy difference 12 meV (24 meV); fine-structure splitting
$\delta_{1}=$0.14 meV ($\delta_{1}=$0.47 meV); $g$-factor $g=$2.12 ($g=$1.71);
diamagnetic shift $\gamma=$2.5 $\mu$eV$/$T$^{2}$ ($\gamma=$1.3
$\mu$eV$/$T$^{2}$). We find also statistically significant correlations between
various parameters describing internal structure of excitonic complexes.
