Tabela com uma seção de descrição

Question

Estou tendo alguns problemas com o pacote xltabular ao tentar desenhar essa tabela, o problema quando tento fazer outras tabelas o resultado será igual ao primeiro, mas quando eu excluo o pacote do meu tex principal a tabela fica completa. Então, posso fazer isso sem usar este pacote? O código da primeira tabela

{

\begin{xltabular}{\linewidth}{ l | X }
  \caption{Data description  of dependent \& independent variables.}
 \label{table: vardescription}\\
 \hline \hline

\textbf{\normalsize Variable} & \textbf{\normalsize Description}  \\
 \hline
\endfirsthead
 \hline \hline

\textbf{Excess  returns} & In this research, our main goal is in showing the directional predictability, where the \textbf{dependent variable} is the dummy sign return indicator.
\[ 
\mathit{Excess\ return} =
  \begin{cases}
    1,  \quad\text{if the excess returns is } >0\\
    0, \quad\text{if the excess returns is } < 0 
  \end{cases}
\]
\\ \hline

\textbf{Recession} &
The recession defined by the \textbf{NBER} are used.
\[ \mathit{Recession} =
  \begin{cases}
    1,  \quad\text{if the  economy is in a recession},\\
     0, \quad\text{if the economy  is in an expansion}
  \end{cases}
\]
\\ \hline

\textbf{Dividend to price} & Dividends from past year divided by closing value of index at month end.
      \\[0ex]\hline
\textbf{Earning to price} & Earnings over the past year divided by closing value of index at month end.
     \\[0ex]\hline
\textbf{Term spread} & The 10 year US Treasury Bill less 3 month US Treasury Bill. \\ \hline
\end{xltabular}
}
\begin{table}[htbp]\centering
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\caption{This is the heading}
\caption*{\footnotesize Smaller note of table that describes what the table is all about.}
\begin{tabular}{l*{3}{c}}
\toprule
                &\multicolumn{1}{c}{(1)}   &\multicolumn{1}{c}{(2)}   &\multicolumn{1}{c}{(3)}   \\
                &     Base   &   Robust   &  Cluster   \\
\midrule
Size            &-0.000645   &-0.000645   &-0.000645   \\
                &  (-0.83)   &  (-0.83)   &  (-0.39)   \\
\midrule
Observations    &     5035   &     5035   &     5035   \\
\bottomrule
\multicolumn{4}{l}{\footnotesize \textit{t} statistics in parentheses}\\
\multicolumn{4}{l}{\footnotesize * p<0.10, ** p<0.05, *** p<0.01}\\
\end{tabular}
\end{table}

Answer 1

Para mim funciona bem ao carregar os pacotes relevantes. Adicionei algumas pequenas melhorias e simplificações de código.

\documentclass{article}
\usepackage{xltabular, booktabs}
\usepackage{mathtools} 
\usepackage{siunitx} 

\begin{document}

\begin{xltabular}{\linewidth}{ l | >{\arraybackslash}X }
 \caption{Data description of dependent \& independent variables.}
 \label{table: vardescription}\\
 \hline \hline
%
\textbf{\normalsize Variable} & \textbf{\normalsize Description} \\
 \hline
\endfirsthead
 \hline \hline
%
\textbf{Excess returns} & In this research, our main goal is in showing the directional predictability, where the \textbf{dependent variable} is the dummy sign return indicator.
\[ \textit{Excess\ return} =
 \begin{cases*}
 1, & if the excess returns is $ >0 $,\\
 0, & if the excess returns is $ < 0 $. 
 \end{cases*} \]
\\ \hline
\textbf{Recession} &
The recession defined by the \textbf{NBER} are used.
\[ \textit{Recession} =
 \begin{cases*}
 1, & if the economy is in a recession,\\
 0, & if the economy is in an expansion.
 \end{cases*}\]
\\ \hline
\textbf{Dividend to price} & Dividends from past year divided by closing value of index at month end.
 \\[0ex]\hline
\textbf{Earning to price} & Earnings over the past year divided by closing value of index at month end.
 \\[0ex]\hline
\textbf{Term spread} & The 10 year US Treasury Bill less 3 month US Treasury Bill. \\ \hline
\end{xltabular}

\end{document}