表格占双列页面的页面宽度

Question

我正在写一篇双栏页面的论文，我想插入一个横跨页面宽度的表格。这是我的尝试，但它的输出不是我想要的：表格和文本是分层的！！

    \begin{table}[H]
    \caption{\label{aprio} Comparison results according to the a priori  error rate}
    \begin{center}

    \begin{tabular*}{\textwidth}{|c|p{1.5cm}p{1.5cm}p{1.5cm}||p{1.5cm}p{1.5cm}p{1.5cm}|}
    \hline
    \multirow{4}*{Data sets} & \multicolumn{6}{c|}{A prior error rate}\\
    \cline{2-7} & \multicolumn{3}{c||}{Majority class} & \multicolumn{3}{c|}{Minority class} \\
    \cline{2-7}& Gini's index & Asym. entropy & Proposed entropy& Gini's index & Asym. entropy & Proposed entropy\\
    \hline
     Vertebral& &   &       &   &   &\\
     Haberman&  &   &   &   &   &\\
     Ion&            &  &   &   &   &\\
     Breast&         &  &       &   &   &\\
     Transfusion&   &   &       &   &       &\\
     MagicGamma&     &  &   &   &       &\\
    \hline
    \end{tabular*}
    \end{center}
    \end{table}