\begin{table}%T2
\caption{\label{tab2}RMS of a linear regression between $T_{\rm eff}$ and Str\"
omgren $b{-}y$ using effective temperatures obtained by other
authors and in this study with $N$~common stars.}
%\centering
\par
\begin{tabular}{lccc}
\hline\hline
author  &$N$ & $\sigma_{\rm others}$ K &  $\sigma_{\rm our}$ K \\
\hline
AAMR96  &  30 & 102 & 78 \\
BLG98   &  25 &  71 & 65 \\
DB98    &  29 & 113 & 87 \\
EDV93   &  30 &  63 & 29 \\
\hline
\end{tabular}
\end{table}