\usepackage{booktabs}
\usepackage{amsfonts}
\usepackage{latexsym}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{graphicx}
\usepackage{parskip}
\usepackage[round]{natbib}
\usepackage{amstext}
\usepackage{hyperref}
\usepackage[latin1]{inputenc}

\newcommand{\Rpackage}[1]{{\normalfont\fontseries{b}\selectfont #1}}
\newcommand{\Robject}[1]{\texttt{#1}}
\newcommand{\Rclass}[1]{\textit{#1}}
\newcommand{\Rcmd}[1]{\texttt{#1}}

\newcommand{\RR}{\textsf{R}}

\RequirePackage[T1]{fontenc}
\RequirePackage{graphicx,ae,fancyvrb}
\IfFileExists{upquote.sty}{\RequirePackage{upquote}}{}
\usepackage{relsize}

\DefineVerbatimEnvironment{Sinput}{Verbatim}{baselinestretch=1.05}
\DefineVerbatimEnvironment{Soutput}{Verbatim}{fontfamily=courier,
                                              baselinestretch=1.05,
                                              fontshape=it,
                                              fontsize=\relsize{-1}}
\DefineVerbatimEnvironment{Scode}{Verbatim}{}  
\newenvironment{Schunk}{}{}