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\begin{table}
\centering
\label{tab:tab1}
\begin{tabular}{lcl} 
\toprule
Signal      & Information ratio                            & Asymptotic behavior                                                                                      \\ 
\hline
Hard Labels & $\frac{2n(n+k-1 -n/k)}{(n+k)(n+k-1)(n+k-2)}$ & $\small \rightarrow\begin{cases}O(\frac{1}{n}) & n>>k\\ O(\frac{1}{n}) & n=k \\O(\frac{1}{k^2}) & n<<k\end{cases}$  \\
Soft Labels & $\frac{kn}{(n+k)(n+k-1)}$                    & $ \small  \rightarrow\begin{cases} O(\frac{1}{n}) & n>>k\\ O(1) & n=k \\ O(\frac{1}{k}) & n<<k \end{cases}$          \\
\bottomrule
\end{tabular}
\end{table}
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