Using the MWE below, I want the chapters declaration, preface and abstract to be given a roman number in the table of contents and the rest of the chapters arabic numbers, using the report class. The table of contents, however, seems to ignore the chapters I want to be roman numbered. It is possible if I use memoir rather than report, but than the subsections are not shown in the table of contents.

\documentclass[a4paper,12pt]{report}
\begin{document}
\tableofcontents
\chapter*{Declaration}
\chapter*{Preface}
\chapter*{Abstract}
\chapter{Introduction}
\chapter{Topics in Claims Reserving}
\section{section 1}
\subsection{section2}
\chapter{Conclusion}
\end{document}

• You are aware that \chapter* is the version of \chapter which does not have numbers and no entry to the ToC? No number, no Roman number output ;-) – user31729 May 9 '15 at 14:39
• You seem to want Roman page numbers up to the abstract; is this so? Or do you mean Roman numbers for the chapters like “Chapter I Declaration” and “Chapter II Preface”? – egreg May 9 '15 at 14:40
• @egreg: No, I think the OP wants Roman chapter numbering: Chapter I, Chapter II ... – user31729 May 9 '15 at 14:41
• Note that in order to have subsections in the TOC with memoir, you just have to issue \settocdepth{subsection} in the preamble. – egreg May 9 '15 at 14:44
• The missing entries for subsection can be obtained by saying \setcounter{tocnumdepth}{2} and \setcounter{secnumdepth}{2} – user31729 May 9 '15 at 14:44

You can use book and then it has \frontmatter for the very same purpose. (Same is possible with memoir, you can always change the tocdepth)

\documentclass[a4paper,12pt]{book}
\begin{document}
\frontmatter
\tableofcontents
\chapter{Declaration}
\chapter{Preface}
\chapter{Abstract}
\mainmatter
\chapter{Introduction}
\chapter{Topics in Claims Reserving}
\section{section 1}
\subsection{section2}
\chapter{Conclusion}
\end{document}


If you want report, you have to do this:

\documentclass[a4paper,12pt]{report}
\begin{document}
\pagenumbering{roman}
\tableofcontents
\chapter*{Declaration}
\chapter*{Preface}
\chapter*{Abstract}
\cleardoublepage
\pagenumbering{arabic}
\chapter{Introduction}
\chapter{Topics in Claims Reserving}
\section{section 1}
\subsection{section2}
\chapter{Conclusion}
\end{document}


For all the odd things that may happen (and I don't understand properly)

\documentclass[a4paper,12pt]{report}
\usepackage{tocloft}
\setlength{\cftchapnumwidth}{3em}
\cftsetindents{section}{3em}{1.5em}
\cftsetindents{subsection}{4.5em}{2.5em}
\begin{document}
\renewcommand{\thechapter}{\Roman{chapter}}
\tableofcontents
\chapter{Declaration}
\chapter{Preface}
\chapter{Abstract}
\cleardoublepage
\setcounter{chapter}{1}
\renewcommand{\thechapter}{\arabic{chapter}}
\pagenumbering{arabic}
\chapter{Introduction}
\chapter{Topics in Claims Reserving}
\section{section 1}
\subsection{section2}
\chapter{Conclusion}
\end{document}


• Omitting the * is easy:-P. I still believe that the OP wants Roman Chapter numbers, not page numbers – user31729 May 9 '15 at 14:42
• @ChristianHupfer, without star they will be numbered. I guess that the OP doesn't want that. – Sigur May 9 '15 at 14:47
• @Sigur: Yes, perhaps... it's unclear – user31729 May 9 '15 at 14:49
• @ChristianHupfer, his MWE contains stared version and so doesn't appear in TOC. – Sigur May 9 '15 at 14:51
• @Sigur: I know that all, but the question is unclear. I think the OP is unaware about the * feature ;-) – user31729 May 9 '15 at 14:57