
## Cost-effectiveness plane

The following graph shows the _cost-effectiveness plane_. This presents the joint distribution of the population average benefit and cost differential, $(\Delta_e,\Delta_c)$ and can be used to assess the uncertainty underlying the decision-making problem. 

Each point in the graph represents a 'potential future' in terms of expected incremental economic outcomes. The shaded portion of the plane is the _'sustainability area'_. The more points lay in the sustainability area, the more likely that the reference intervention will turn out to be cost-effective, at a given willingness to pay threshold, $k$ (in this case selected at $k=$ `r params$wtp`).


```{r, echo=echo, fig.width=4.6, fig.height=4.6, fig.align=align, warning=FALSE, message=FALSE, comment=NA}
n.ints <- m$n_comparators

if (n.ints == 2) {
  graph <- "base"
  pos <- c(1, 1)
} else {
  graph <- "ggplot2"
  pos <- TRUE
}
ceplane.plot(m, graph = graph, pos = pos, wtp = params$wtp)
```
