\begin{table}%t4
%\centering
\par
\caption{\label{amp-amp_sum}Slopes of the linear relationships between various amplitudes 
(omitting the known binaries). ``Ratio'' refers to the rate of slopes
in the sense value for long- over value for short-period Cepheids.}
\small
\begin{tabular}{l@{\hskip5mm}r@{\hskip2mm}l@{\hskip2mm}r@{\hskip5mm}r@{\hskip2mm}l@{\hskip2mm}r@{\hskip5mm}r@{\hskip7mm}r@{\hskip2mm}l@{\hskip2mm}r}
\hline\hline
\noalign{\smallskip}
 & Slope & $\sigma_{\rm slope}$ & $N$ & Slope & $\sigma_{\rm slope}$ & $N$ & Ratio & Slope & $\sigma_{\rm slope}$ & $N$\\
\noalign{\smallskip}
\cline{2-7} \cline{9-11}
\noalign{\smallskip}
Amplitudes & \multicolumn{7}{c}{Fundamental mode} & \multicolumn{2}{c}{1st overtone}\\
\noalign{\smallskip}
involved & \multicolumn{3}{c}{$\log P < 1.02$} & \multicolumn{3}{c}{$\log P > 1.02$} & & \\
\hline
\noalign{\smallskip}
$A_U$~--~$A_V$ & 1.856 & 0.027 & 18 & 2.192 & 0.037 & 22 & {\em 1.182} & 1.940 & 0.045 & 8 \\
$A_B$~--~$A_V$ & 1.449 & 0.007 & 119 & 1.515 & 0.008 & 54 & {\em 1.046} & 1.471 & 0.007 & 30 \\
$A_R$~--~$A_V$ & 0.784 & 0.003 & 118 & 0.779 & 0.004 & 56 & {\em 0.994} & 0.808 & 0.005 & 28 \\
$A_I$~--~$A_V$ & 0.622 & 0.004 & 90 & 0.606 & 0.005 & 49 & {\em 0.974} & 0.620 & 0.003 & 24 \\
$A_{V_{\rm RAD}}$~--~$A_V$ & 47.93 & 0.73 & 64 & 47.76 & 0.86 & 35 & {\em 0.996} & 50.93 & 0.90 & 26 \\
$A_R$~--~$A_B$ & 0.540 & 0.002 & 111 & 0.513 & 0.004 & 51 & 0.950 & 0.548 & 0.008 & 28 \\
$A_I$~--~$A_B$ & 0.424 & 0.003 & 82 & 0.398 & 0.004 & 46 & 0.939 & 0.423 & 0.007 & 24 \\
$A_{V_{\rm RAD}}$~--~$A_B$ & 32.81 & 0.50 & 63 & 31.12 & 0.59 & 33 & 0.948 & 34.62 & 0.92 & 26\\
\noalign{\smallskip}
\hline
\end{tabular}
\end{table}