\documentclass{article}
\usepackage{sparklines}
\usepackage{graphicx}
\usepackage{color,ifthen}
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\begin{document}
\section{Handling Noise in Data}

\begin{figure}[!h]
\begin{center}
\begin{tabular}{p{0.2in}@{}c@{}c}
&KNN & CLIFF\\
pd&\includegraphics[width=2.5in]{knnpd.pdf} &
\includegraphics[width=2.5in]{cliffpd.pdf}
\\\hline
prec&\includegraphics[width=2.5in]{knnprec.pdf} &
\includegraphics[width=2.5in]{cliffprec.pdf}
\\\hline
pf&\includegraphics[width=2.5in]{knnpf.pdf} &
\includegraphics[width=2.5in]{cliffpf.pdf}
\\
\end{tabular}
\end{center}
\caption{Effects of noise.}
\end{figure}

\section{Is CLIFF better than Others?}
\begin{figure}[!h]
\renewcommand{\baselinestretch}{0.7}
{\scriptsize
\begin{tabular}{lr|rrrrr|r}
& & \multicolumn{5}{c}{percent noise}&\\
& & 0 & 10 & 20 & 30 & 40&sum\\\hline
\input{pds}
\end{tabular}
}
\caption{PDs: other - (knn+cliff). Note: {\em negative} values means CLIFF is performing {\em better}.} 
\end{figure}

\begin{figure}[!h]
\renewcommand{\baselinestretch}{0.7}
{\scriptsize
\begin{tabular}{lr|rrrrr|r}
& & \multicolumn{5}{c}{percent noise}&\\
& & 0 & 10 & 20 & 30 & 40&sum\\\hline
\input{pfs}
\end{tabular}
}
\caption{PFs: other - (knn+cliff). Note: {\em positive} values means CLIFF is performing {\em better}.} 
\end{figure}

\begin{figure}[!h]
\renewcommand{\baselinestretch}{0.7}
{\scriptsize
\begin{tabular}{lr|rrrrr|r}
& & \multicolumn{5}{c}{percent noise}&\\
& & 0 & 10 & 20 & 30 & 40&sum\\\hline
\input{precs}
\end{tabular}
}
\caption{PRECISION: other - (knn+cliff). Note: {\em negative} values means CLIFF is performing {\em better}.} 
\end{figure}
\end{document}
