groups (Diaferio, Geller & Ramella 1994). In this section, we consider the distributions of various compact group properties separately for groups of $N= 3$ and groups of $N \geq 4$. One physical motivation is the much greater likelihood that tight groups of $N \geq 4$ are bound. Diaferio, Geller & Ramella (1994) find that within loose groups only 50% of triplets are bound systems, whereas 80% of systems with four or more galaxies are bound systems.

Velocity Dispersion
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In Figures \[fig:veldisp\]a and b, we plot the distribution of the velocity dispersions of the HCG’s (dashed line) and of the 89 RSCG’s (solid line). Figure \[fig:veldisp\]a is the distribution for groups of 3 and Figure \[fig:veldisp\]b includes only groups of $N \geq 4$. Table \[tab:veldisp\] lists the median, first and third quartiles of these distributions. The distributions are similar. K-S tests indicate that the probability these samples are drawn from the same parent distribution is $86.5\% $ for groups with $N=3$ and $26.5\% $ for groups with $N \geq 4$.

Density
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We also compare the group densities. We choose the density statistic $n=\frac{3N}{4 \pi R^{3}}$, with $N$ the number of detected galaxies and $R$ the radius of the smallest 