将不同数据集中的 geom_text 添加到 geom_bar

Question

我有一个带有分面网格的条形图，我想添加每个子图中存储在单独数据框中的观察数。

条形图是用

bar.plot <- ggplot(BarDiff.m.s, aes(x=value.change, fill=incompatibility))+
  geom_bar(binwidth=1)+
  labs(x="score differences", y="count / years since start of PSA")+
  geom_vline(aes(xintercept=0), linetype="dotted")+
  theme(plot.title=element_text(face="bold", size=10),
        legend.position= "bottom")+
  scale_fill_brewer(palette="Set1")+
 facet_grid(years.since.peace ~ strategy.cm6.YP, space="free")

我尝试通过在 geom_bar 行之后添加来添加 geom_text

   geom_text(data=num.obs, aes(label=paste("obs=",num.obs),y=4,x=min(BarDiff.m.s$value.change)))

但是，我收到了错误消息

Error in eval(expr, envir, enclos) : object 'incompatibility' not found

显然，出于某种原因，我必须考虑 geom_text 中的“填充”变量；我试图将 group=BarDiff.ms$incompatibility 添加到 geom_text，但无济于事。

我已经看到如何在 R 中使用 ggplot/geom_bar 从条形顶部的数据集中添加自定义标签？，但如果可能的话，我想将两个 data.frames 分开并了解如何解决“填充”问题。非常欢迎任何建议！谢谢。

该图的相关数据是

BarDiff.m.s <- structure(list(value.change = c(-1, -1, -2, -2, 1, NA, 0, -2, 
-1, -2, NA, 2, -3, NA, NA, -3, -2, -1, -4, -1, -3, -1, 2, 2, 
NA, 1, -1, 0, 0, -2, -2, -2, -1, 1, NA, -1, -1, 0, -2, NA, 0, 
-4, NA, NA, NA, -3, -1, -4, -2, -3, -2, -1, 0, NA, NA, 0, -4, 
NA, -2, -2, -3, -1, NA, NA, -1, -1, 0, -2, NA, 0, NA, NA, NA, 
NA, -4, NA, -4, -2, -3, -2, -2, 2, NA, NA, 0, -4, -2, NA, NA, 
NA, NA, NA, NA, -1, NA, NA, NA, NA, 0, NA, NA, NA, NA, NA, NA, 
-4, NA, -2, -1, -2, NA, NA, NA, NA, -3, 1), incompatibility = structure(c(1L, 
1L, 1L, 2L, 2L, 2L, 2L, 1L, 2L, 1L, 2L, 1L, 1L, 1L, 2L, 2L, 2L, 
2L, 1L, 2L, 2L, 2L, 1L, 1L, 2L, 1L, 2L, 1L, 1L, 1L, 1L, 1L, 2L, 
2L, 2L, 2L, 1L, 2L, 1L, 2L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 1L, 2L, 
2L, 2L, 1L, 1L, 2L, 1L, 2L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 
1L, 2L, 1L, 2L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 1L, 2L, 2L, 2L, 1L, 
1L, 2L, 1L, 2L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 1L, 2L, 1L, 
2L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 1L, 2L, 2L, 2L, 1L, 1L, 2L, 1L, 
2L, 1L, 1L), .Label = c("territory", "government"), class = "factor"), 
    years.since.peace = structure(c(5L, 5L, 5L, 5L, 5L, 5L, 5L, 
    5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 
    5L, 5L, 5L, 5L, 5L, 5L, 5L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 
    6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 
    6L, 6L, 6L, 6L, 6L, 6L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 
    7L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 
    7L, 7L, 7L, 7L, 7L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 
    8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 
    8L, 8L, 8L, 8L), .Label = c("y0", "y10", "y15", "y20", "diff.y5", 
    "diff.y10", "diff.y15", "diff.y20"), class = "factor"), strategy.cm6.YP = structure(c(4L, 
    4L, 5L, 1L, 1L, 4L, 3L, 4L, 3L, 1L, 1L, 1L, 3L, 4L, 4L, 4L, 
    4L, 3L, 3L, 4L, 4L, 4L, 1L, 4L, 5L, 1L, 4L, 1L, 4L, 4L, 4L, 
    5L, 1L, 1L, 4L, 3L, 4L, 3L, 1L, 1L, 1L, 3L, 4L, 4L, 4L, 4L, 
    3L, 3L, 4L, 4L, 4L, 1L, 4L, 5L, 1L, 4L, 1L, 4L, 4L, 4L, 5L, 
    1L, 1L, 4L, 3L, 4L, 3L, 1L, 1L, 1L, 3L, 4L, 4L, 4L, 4L, 3L, 
    3L, 4L, 4L, 4L, 1L, 4L, 5L, 1L, 4L, 1L, 4L, 4L, 4L, 5L, 1L, 
    1L, 4L, 3L, 4L, 3L, 1L, 1L, 1L, 3L, 4L, 4L, 4L, 4L, 3L, 3L, 
    4L, 4L, 4L, 1L, 4L, 5L, 1L, 4L, 1L, 4L), .Label = c("none", 
    "only offered", "communication/\nfacilitation", "procedural", 
    "directive", "unspecified"), class = "factor")), .Names = c("value.change", 
"incompatibility", "years.since.peace", "strategy.cm6.YP"), class = "data.frame", row.names = c(1298L, 
1299L, 1335L, 1339L, 1340L, 1341L, 1344L, 1372L, 1379L, 1386L, 
1387L, 1402L, 1415L, 1439L, 1449L, 1454L, 1455L, 1456L, 1463L, 
1466L, 1470L, 1496L, 1497L, 1498L, 1525L, 1536L, 1542L, 1546L, 
1563L, 1617L, 1618L, 1654L, 1658L, 1659L, 1660L, 1663L, 1691L, 
1698L, 1705L, 1706L, 1721L, 1734L, 1758L, 1768L, 1773L, 1774L, 
1775L, 1782L, 1785L, 1789L, 1815L, 1816L, 1817L, 1844L, 1855L, 
1861L, 1865L, 1882L, 1936L, 1937L, 1973L, 1977L, 1978L, 1979L, 
1982L, 2010L, 2017L, 2024L, 2025L, 2040L, 2053L, 2077L, 2087L, 
2092L, 2093L, 2094L, 2101L, 2104L, 2108L, 2134L, 2135L, 2136L, 
2163L, 2174L, 2180L, 2184L, 2201L, 2255L, 2256L, 2292L, 2296L, 
2297L, 2298L, 2301L, 2329L, 2336L, 2343L, 2344L, 2359L, 2372L, 
2396L, 2406L, 2411L, 2412L, 2413L, 2420L, 2423L, 2427L, 2453L, 
2454L, 2455L, 2482L, 2493L, 2499L, 2503L, 2520L))

观察次数的数据为：

num.obs <- structure(list(years.since.peace = structure(c(5L, 5L, 5L, 5L, 
6L, 6L, 6L, 6L, 7L, 7L, 7L, 7L, 8L, 8L, 8L, 8L), .Label = c("y0", 
"y10", "y15", "y20", "diff.y5", "diff.y10", "diff.y15", "diff.y20"
), class = "factor"), strategy.cm6.YP = structure(c(1L, 3L, 4L, 
5L, 1L, 3L, 4L, 5L, 1L, 3L, 4L, 5L, 1L, 3L, 4L, 5L), .Label = c("none", 
"only offered", "communication/\nfacilitation", "procedural", 
"directive", "unspecified"), class = "factor"), num.obs = c(8L, 
5L, 14L, 2L, 8L, 5L, 14L, 2L, 8L, 5L, 14L, 2L, 8L, 5L, 14L, 2L
)), .Names = c("years.since.peace", "strategy.cm6.YP", "num.obs"
), row.names = c(NA, -16L), class = "data.frame")

Answer 1

将填充美学移动到 geom_bar 并更改 geom_text 的 y 位置应该可以满足您的需求。

bar.plot <- ggplot(BarDiff.m.s, aes(x = value.change)) +
  geom_bar(aes( fill = incompatibility), binwidth = 1) +
  geom_text(data = num.obs, aes(label = paste("obs=", num.obs),y = 4, x = -4)) +
  labs(x = "score differences", y = "count / years since start of PSA") +
  geom_vline(aes(xintercept = 0), linetype = "dotted") +
  theme(plot.title = element_text(face = "bold", size = 10),
        legend.position = "bottom") +
  scale_fill_brewer(palette = "Set1") +
  facet_grid(years.since.peace ~ strategy.cm6.YP, space = "free")

bar.plot

如果您希望文本标签按 value.change 在第一个数据集中定位，可能最简单的方法是将相关列合并到第二个数据集中。