\begin{table}%t3
\caption{Mean reddening in the observer's frame, $\langle E \rangle$, and mean extinction in the rest frame, $\langle A_{\rm V} \rangle$,  for different colors and DLA/QSO~samples.}\label{tab3}
\small%\centerline
 {
\begin{tabular}{ccccccccc}
\hline \hline
Color & & & $(r-z)$   & & & & $(g-z)$     & \\
Redshift interval & & & $2.25 \leq z_{\rm e} \leq 3.5$   & & & & $2.25 \leq z_{\rm e} \leq 3.4$     & \\
\hline
Absorption
 &   $n$   & ${\langle E(r-z) \rangle}$ & $\langle A_{\rm V} \rangle$ & $\langle A_{\rm V}/N(\ion{H}{i}) \rangle$  
 &   $n$   & ${\langle E(g-z) \rangle}$ & $\langle A_{\rm V} \rangle$ & $\langle A_{\rm V}/N(\ion{H}{i}) \rangle$  \\
   sample           &           & [10$^{-3}$ mag]& [10$^{-3}$ mag]   & [10$^{-23}$ mag cm$^2$]          
   &           & [10$^{-3}$ mag] & [10$^{-3}$ mag]  & [10$^{-23}$ mag cm$^2$] \\
\hline
1$^a$  &  248   & 27 $\pm$ 8.8 & 19 $\pm$ 5.9 & 4.1 & 232 & 54 $\pm$ 12  &  17 $\pm$ 3.8 & 3.2 \\ 
2$^b$  & 247 & 24 $\pm$ 8.3 & 17 $\pm$ 5.6 & 3.5 & 231 & 51 $\pm$ 12 & 16 $\pm$ 3.7 & 2.8\\
3$^c$  & 246 & 22 $\pm$ 8.0 & 16 $\pm$ 5.4 & 3.0 & 229 & 48 $\pm$ 11 & 15 $\pm$ 3.5 & 2.4\\ 
\hline
&&&&&&&& \\[-8pt]
Bootstrap$^d$ & 248 & 27 $\pm$ 9.2 &  &  &  232 &  54 $\pm$ 14 & & \\
\hline 
\end{tabular}}
\medskip
$^a$ Complete absorption sample of Table~\ref{tab1}. \\
$^b$ Cases with $\Delta_i  > \langle \Delta \rangle + 5 \times \sigma$ are excluded from the
complete sample ($\sigma = \sigma_m \times \sqrt{n}$). \\
$^c$ Cases with $\Delta_i  > \langle \Delta \rangle + 3 \times \sigma$ are excluded from the
complete sample.\\ 
$^d$ Mean and standard deviation of the mean color excess of 10~000~bootstrap samples obtained from the absorption sample~1. 
\end{table}