diff --git a/R/rankingHeatmap.R b/R/rankingHeatmap.R
index 82bfbcf..6c71d59 100644
--- a/R/rankingHeatmap.R
+++ b/R/rankingHeatmap.R
@@ -1,63 +1,98 @@
+#' @export
 rankingHeatmap <- function(x,...) UseMethod("rankingHeatmap")
+
+#' @export
 rankingHeatmap.default <- function(x, ...) stop("not implemented for this class")
 
+#' Creates ranking heatmaps
+#'
+#' Creates ranking heatmaps from one or more ranked assessment data sets.
+#'
+#' @param x The ranked asssessment data set.
+#' @param ties.method A string specifying how ties are treated, see [base::rank()].
+#' @param ... Further arguments passed to or from other functions.
+#'
+#' @return
+#'
+#' @examples
+#'
+#' @seealso `browseVignettes("challengeR")`
+#'
+#' @family functions to visualize assessment data
+#' @export
 rankingHeatmap.ranked.list=function (x,ties.method="min",...) {
 
   xx=x$data
 
   a=lapply(names(x$matlist),function(subt){
     ordering=rownames(x$matlist[[subt]])[order(x$matlist[[subt]]$rank)]
 
     dd=as.challenge(xx[[subt]],
                     value=attr(xx,"value"),
                     algorithm=attr(xx,"algorithm") ,
                     case=attr(xx,"case"),
                     by=attr(xx, "by"),
                     annotator = attr(xx,"annotator"),
                     smallBetter = attr(xx,"smallBetter"),
                     na.treat=x$call[[1]][[1]]$na.treat)
 
     rankingHeatmap(dd,
                    ordering=ordering,
                    ties.method=ties.method,...) + ggtitle(subt)
   })
 
   # Remove title for single-task data set
   if (length(a) == 1) {
     a[[1]]$labels$title <- NULL
   } else {
     names(a) = names(x$matlist)
   }
 
   class(a) <- "ggList"
   a
 }
 
-
+#' Creates a ranking heatmap
+#'
+#' Creates a ranking heatmap from a challenge object.
+#'
+#' @param x The challenge object.
+#' @param ordering
+#' @param ties.method A string specifying how ties are treated, see [base::rank()].
+#' @param ... Further arguments passed to or from other functions.
+#'
+#' @return
+#'
+#' @examples
+#'
+#' @seealso `browseVignettes("challengeR")`
+#'
+#' @family functions to visualize assessment data
+#' @export
 rankingHeatmap.challenge=function(x,
                                   ordering,
                                   ties.method="min",...) {
   ranking=x%>%rank( ties.method = ties.method )
 
   task <- ranking$matlist[[1]]
 
   dat=as.data.frame(table(task[[attr(x,"algorithm")]],
                           task$rank,
                           dnn=c("algorithm","rank")),
                     responseName = "Count")
   dat$algorithm=factor(dat$algorithm, levels=ordering)
   ncases=length(unique(task[[attr(x,"case")]]))
   ggplot(dat)+
     geom_raster(aes(algorithm, rank, fill= Count))+
     geom_hline(yintercept = seq(1.5,max(task$rank)-.5,by=1),
                color=grey(.8),size=.3)+
     geom_vline(xintercept = seq(1.5,length(unique(dat$algorithm))-.5,by=1),
                color=grey(.8),size=.3)+
     scale_fill_viridis_c(direction = -1,
                          limits=c(0,ncases)
     )+
     theme(axis.text.x = element_text(angle = 90),
           aspect.ratio=1)+
     xlab("Algorithm")+
     ylab("Rank")
 }