\documentclass{beamer}
\usepackage{hyperref}
\usepackage[english]{babel}
%\usepackage{natbib}
\mode<presentation>
  \usetheme{Warsaw}
  \setbeamercovered{transparent}
\title[] % (optional, use only with long paper titles)
{Category discrimination by infants}

\subtitle {A talk on {\em Basic-level category discriminations by 7- and 9-months-old in an object examination task} by Denis Mareschal, Daisy Powell and Agnes Volein}

\author[] % (optional, use only with lots of authors)
{Andreas van Cranenburgh}

\institute[] % (optional, but mostly needed)
{Universiteit van Amsterdam}

\date[] % (optional)
{November 7th, 2007}

\subject{Talks}
% This is only inserted into the PDF information catalog. Can be left
% out.

% If you have a file called "university-logo-filename.xxx", where xxx
% is a graphic format that can be processed by latex or pdflatex,
% resp., then you can add a logo as follows:

 %\pgfdeclareimage[height=0.5cm]{university-logo}{university-logo-filename}
 %\logo{\pgfuseimage{university-logo}}

% Delete this, if you do not want the table of contents to pop up at
% the beginning of each subsection:
%\AtBeginSubsection[]
%{
%  \begin{frame}<beamer>
%    \frametitle{Outline}
%    \tableofcontents[currentsection,currentsubsection]
%  \end{frame}
%}


% If you wish to uncover everything in a step-wise fashion, uncomment
% the following command:

%\beamerdefaultoverlayspecification{<+->}

\begin{document}
\section{Title}
\begin{frame}
  \titlepage
\end{frame}

\section{Abstract}
\begin{frame}
{\bf Abstract} 
\begin{itemize}
\item Infants can separate cat and dog figures \medskip
\item Cats are easier to distinguish from dogs than vice versa \medskip 
\item Categories are based on feature distributions \medskip
\end{itemize}

\end{frame}

\section{Introduction}
\begin{frame}
{\bf Introduction}
\bigskip

A basic-level category is maximally informative:

\begin{itemize}
\item most common attributes shared with its members \medskip
\item least attributes shared with other categories \medskip
\end{itemize}

\end{frame}
\newpage

\begin{frame}
\bigskip
``Conceptual structure'' might be in place at birth

\bigskip

Open question: are initial concept broad and narrowed down gradually, or the other way around?

\bigskip

Some research claims the former; only after 11 months cats and dogs would be distinguished
\end{frame}

\newpage

\begin{frame}
\bigskip

However, {\em preferential looking} methods suggest the contrary. (Eimas et al, 1994)

\bigskip

Infants are shown photos. On the basis of attention the category forming is revealed.

\begin{itemize}
\item According to research, 3- to 4- month-olds can discriminate between basic level objects
\item A catogory of cats excluded dogs birds, dogs, horses and tigers
\item Mammals were excluded from birds and fish
\end{itemize}
\end{frame}

\newpage

\begin{frame}
\bigskip

Critics argue that visual preference says nothing about conceptual capabilities:

\begin{itemize}
\item perceiving is different from acting upon
\end{itemize}

\bigskip

However, the paper to be discussed (Mareschal et al, 2002) argues that whether visual or tactile, {\em feature-based recognition occurs} 

\begin{itemize}
\item Discrimination seems to correlate with variability of stimuli
\item Cats and dogs are familiarized in separate experiments
\end{itemize}
\end{frame}

\newpage

\begin{frame}
The experiments:

\begin{itemize}
\item Each experiment: 30 infants (7 and 9 month-old)
\item Experiment 1: 4 cats during familiarization
\item Experiment 2: 4 dogs during familiarization
\item Remaining figures presented in test trials \\ (more cats \& dogs, and an eagle)
\end{itemize}

During test trials, the examining times were measured. Longer means more novel.
\end{frame}

\newpage

\begin{frame}

Analysis of data reveals these results for cats (experiment 1):
\begin{itemize}
\item Significant decrease in examination time between first and second trial
\item Examination times correlate negatively with similarity
\end{itemize}

Also, analyzing the figures and their features shows:
\begin{itemize}
\item Only external body features contribute to discrimination
\item ...whereas head and facial features do not contribute significantly to discrimination.
\end{itemize}
\end{frame}

\newpage

\begin{frame}

Analysis of data reveals these results for dogs (experiment 2):
\begin{itemize}
\item First and second trial do not differ significantly
\item Category includes both dogs and cats, but excludes eagles
\end{itemize}

Also, analyzing the figures and their features shows:
\begin{itemize}
\item Facial features contribute to discrimination
\item ...whereas the other features do not contribute significantly to discrimination.
\end{itemize}
\end{frame}

\newpage
\section{Conclusion}
\begin{frame}
{\bf Conclusion}
\begin{itemize}
\item Cats are `more similar' to dogs than vice versa (dogs subsume cats)
\item Children use bottom-up strategies for discrimination (hence the assymmetry)
\item ... unlike adults, who (presumably) use top-down approaches
\item Object-examination tasks do not necessarily require conceptual processing (alternative: feature distribution)
\end{itemize}
\end{frame}

\newpage
\section{Bibliography}
\begin{frame}
{\bf Bibliography}
%\bibliographystyle{plainnat}
\begin{thebibliography}{9}

\bibitem{Mareschal} 
	Denis Mareschal, Daisy Powell and Agnes Volein,
	\emph{Basic-level category discriminations by 7- and 9-months-old in an object examination task},
	Journal of Experimental Child Psychology, 86, 87-107 (2002).

\bibitem{Eimas}
	Peter D. Eimas, Pail C. Quinn and Pamela Cowan,
	\emph{Development of Exclusivity in Perceptually Based Categories of Young Infants},
	Journal of Experimental Child Psychology, 58, 418-431 (1994).

\end{thebibliography}
\end{frame}
\end{document}