\section{Introduction}

The Grateful Dead were an American band which, despite relatively little popular radio airtime, enjoyed a cult-like following from a fan base that numbered in the millions \cite{trip:mcnally2002}. The Grateful Dead originated in San Francisco, California in the early 1960s and toured the world playing concerts until the untimely death of the foreman and lead guitarist Jerry Garcia in 1995. The primary source of revenue and exposure for the band came through their concert tours.   They played over 37,000 songs live, in some 2,300 concerts over their 30 years as a band~\cite{setlists:1996}. Throughout their years together, the Grateful Dead accumulated a large repertoire that included over 450 unique songs \cite{setlists:1996}. The Grateful Dead's success and continuity across multiple generations of music listeners is perhaps due in part to their fundamentally eclectic nature. The band utilized many song writers, composers and singers, and this resulted in a broad diversity in sound. Robert Hunter and John Barlow were the primary lyricists for scores written by Jerry Garcia and Bob Weir, respectively \cite{annotatedead:dobb2007}. While Jerry Garcia and Bob Weir were the primary singers as well, other singers included Ron McKernan, Brent Mydland, and Phil Lesh. Moreover, their eclectic nature can be seen in the large number of graphic icons they used to represent themselves. These icons include skeletons, roses, dancing bears, terrapins, etc. Perhaps their most famous and recognizable image is the ``Steal Your Face'' icon in Figure \ref{fig:stealyourface} that was released as the album cover art to the live 1976 \album{Steal Your Face} album.