\begin{figure*}[t]
    \centering
<<fig=TRUE,height=3>>=
    cummrr <- positions
    cummrr <- cummrr[cummrr$latest,]
    cummrr <- cummrr[cummrr$frm,]
    cummrr <- cummrr[cummrr$evaluator %in% c('CorpusEvaluator', 'LinearEvaluator.all'),]
    cummrr <- ddply(cummrr, .(project, evaluator), function(x) data.frame(display_order=order(order(x$bug_number)), cummrr=cumulative_mean(x$rr)))
    cummrr$project <- format_name(cummrr$project)
    cummrr$evaluator <- format_name(cummrr$evaluator)
    fig <- ggplot(cummrr, aes(display_order, cummrr, linetype=evaluator)) +
        geom_line() +
        scale_y_log10() +
        facet_grid(. ~ project, scales='free') +
        labs(x='', y='Cumulative MRR') +
        theme(axis.text=element_text(colour='black'),
              axis.text.x=element_text(angle=90),
              legend.position='bottom',
              legend.title=element_blank(),
              panel.border=element_rect(colour='black', fill=NA)
        )
    print(fig)
@
    \caption{Cumulative MRR for combined and corpus approaches. Bugs ordered by report date.}
    \label{fig:cumulative_mrr}
\end{figure*}
