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\begin{document}
\begin{titlepage}
\title{Placeholder\thanks{abc}}
\author{Hyunwoo Park\thanks{abc} \and John Smith\thanks{abc}}
\date{\today}
\maketitle
\begin{abstract}
\noindent Placeholder\\
\vspace{0in}\\
\noindent\textbf{Keywords:} key1, key2, key3\\
\vspace{0in}\\
\noindent\textbf{JEL Codes:} key1, key2, key3\\
\bigskip
\end{abstract}
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\doublespacing
\section{Introduction} \label{sec:introduction}
\section{Literature Review} \label{sec:literature}
\section{Data} \label{sec:data}
\section{Results} \label{sec:result}
\section{Discussions} \label{sec:discussion}
\section{Conclusion} \label{sec:conclusion}
\singlespacing
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\onehalfspacing
\section*{Tables} \label{sec:tab}
\addcontentsline{toc}{section}{Tables}
\clearpage
\section*{Figures} \label{sec:fig}
\addcontentsline{toc}{section}{Figures}
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% \caption{Placeholder}
% \label{fig:placeholder}
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\section*{Appendix A. Placeholder} \label{sec:appendixa}
\addcontentsline{toc}{section}{Appendix A}
\end{document}
