\begin{quote}
This article was published as {\it A measure of total research impact independent of time and discipline}. Alberto Pepe, Michael J. Kurtz. PLoS One. 7(11): e46428. \url{doi:10.1371/journal.pone.00464282012}. (Open Access Article)
\end{quote}

{\small \textbf{Abstract}. Authorship and citation
practices evolve with time and differ by academic discipline. As such,
indicators of research productivity based on citation records are
naturally subject to historical and disciplinary effects. We observe
these effects on a corpus of astronomer career data constructed from a
database of refereed publications. We employ a simple mechanism to
measure research output using author and reference counts available in
bibliographic databases to develop a citation-based indicator of
research productivity. The total research impact (tori) quantifies,
for an individual, the total amount of scholarly work that others have
devoted to his/her work, measured in the volume of research papers. A derived measure, the research
impact quotient (riq), is an age independent measure of an individual's
research ability. We demonstrate that these measures are substantially less
vulnerable to temporal debasement and cross-disciplinary bias than the
most popular current measures. The proposed measures of research
impact, tori and riq, have been implemented in
the Smithsonian/NASA Astrophysics Data System.}
