在ggplot2中，coord_flip和freescale不能一起工作

以下是一些关于体育促进干预措施有效性的假设荟萃分析的示例数据，我想为其创建一个森林图：

example.df = data.frame(Author = c("McAuliffe et al.", "Palen et al.", "Manning et al.", "Richters et al.", "Grello et al.","Mpofu et al.", "Kuo & St Lawrence", "Langstrom & Hanson", "Ompad et al.", "Abdullah et al.","Yan", "Peltzer & Pengpid", "Lo & Wei", "Haggstrom-Nordin et al.", "Mwaba & Naidoo", "Hughes et al.","Lydie et al.", "Zimmer-Gembeck et al.", "Babalola", "Garos et al.", "Pinkerton et al."),
                    Sport = c("Basketball", "Basketball", "Baseball", "Dance", "Baseball", "Dance", "Wrestling","Wrestling", "Dance", "Baseball", "Wrestling", "Dance", "Swimming", "Swimming","Basketball", "Basketball", "Basketball", "Basketball", "Basketball", "Swimming", "Wrestling"),
                    Gender = c("Male", "Female", "Male", "Male", "Female", "Male", "Male", "Male", "Male", "Female","Female", "Male", "Female", "Female", "Female", "Male", "Female", "Female", "Female", "Male", "Female"),
                    d = c(-0.12, 0.53, 0.11, 0.02, 0.32, 0.04, 0.03,0.04,0.26, 0.76, 1.11, 0.34, 0.77, 1.19, 0.59, 0.15, 0.30, 0.81, 0.12, 0.11, 1.01),
                    d_SE = c(.10, .04, .06, .01, .11, .08, .08, .04, .05, .05, .14, .07, .05, .08, .19, .16, .07, .16, .06, .18, .15))

数据框包含作者姓名、运动项目、样本是男性还是女性、干预的效应大小以及效应大小的标准误差。我希望创建一个将形状映射到性别以及特定运动的点图。在遵循张的“食谱”中的示例之后此相关查询 https://stackoverflow.com/questions/19599957/ggplot-confidence-intervals，我提出了以下代码，可以满足我的大部分格式化需求：

p<-ggplot(example.df, aes(x=Author, y=d, ymin=d-1.96*d_SE, ymax=d+1.96*d_SE,shape=Gender))+ 
geom_pointrange() + 
coord_flip()+
scale_y_continuous(limits=c(-2,2),breaks=c(-2,-1.5,-1,-0.5,0,.5,1,1.5,2))+
geom_hline(yintercept=0, color="grey60",linetype="dashed")+
theme_bw()+
theme(panel.grid.major.x=element_blank(),panel.grid.minor.x=element_blank(),panel.grid.major.y=element_line(color="grey60",linetype="dashed"))+
facet_grid(Sport ~ ., scales="free_y")
p

然而，我的问题是，每个方面的结果图（如下）将整个数据框中的每个作者绘制在 y 轴（技术上是 x 轴，但轴被翻转）上。相反，我只希望将具有与给定方面相关的数据的作者绘制在该方面的与作者相关的轴上，因此每个方面应该在轴上具有不同的作者列表。

我原以为scales="free_y"的组成部分facet_grid层将确保每个方面都有一个独特的作者轴（我也尝试过scales="free_x"，给定倒轴），但这没有达到预期的效果。

有谁知道我可以确保每个方面的轴上出现的唯一作者姓名是与该方面相关的数据的方法吗？

安德里是对的coord_flip()似乎是问题的根源。然而，森林图格式的约定是在 y 轴上显示作者姓名，因此我想找到一种仍然满足此格式要求的方法。

中接受的答案post https://stackoverflow.com/questions/10183292/how-can-i-remove-empty-factors-from-ggplot2-facets格雷戈尔评论的实际上解决了我的问题；唯一需要的更改是我必须计算置信区间的上限/下限值的列。

现在有了更新的数据框：

example.df = data.frame(Author = c("McAuliffe et al.", "Palen et al.", "Manning et al.", "Richters et al.", "Grello et al.","Mpofu et al.", "Kuo & St Lawrence", "Langstrom & Hanson", "Ompad et al.", "Abdullah et al.","Yan", "Peltzer & Pengpid", "Lo & Wei", "Haggstrom-Nordin et al.", "Mwaba & Naidoo", "Hughes et al.","Lydie et al.", "Zimmer-Gembeck et al.", "Babalola", "Garos et al.", "Pinkerton et al."),
                    Sport = c("Basketball", "Basketball", "Baseball", "Dance", "Baseball", "Dance", "Wrestling","Wrestling", "Dance", "Baseball", "Wrestling", "Dance", "Swimming", "Swimming","Basketball", "Basketball", "Basketball", "Basketball", "Basketball", "Swimming", "Wrestling"),
                    Gender = c("Male", "Female", "Male", "Male", "Female", "Male", "Male", "Male", "Male", "Female","Female", "Male", "Female", "Female", "Female", "Male", "Female", "Female", "Female", "Male", "Female"),
                    d = c(-0.12, 0.53, 0.11, 0.02, 0.32, 0.04, 0.03,0.04,0.26, 0.76, 1.11, 0.34, 0.77, 1.19, 0.59, 0.15, 0.30, 0.81, 0.12, 0.11, 1.01),
                    d_SE = c(.10, .04, .06, .01, .11, .08, .08, .04, .05, .05, .14, .07, .05, .08, .19, .16, .07, .16, .06, .18, .15),
                    ci.low = c(-.30, .45, .00, -.01, .11, -.12, -.14, -.04, .16, .66, .84, .19, .68, 1.03, .22, -.17, .17, .50, .00, -.23, .72),
                    ci.high = c(.07, .62, .22, .05, .53, .20, .19, .11, .36, .87, 1.38, .47, .86, 1.35, .97,.47, .43, 1.11, .24, .46, 1.30))

#reorder Author based on value of d, so effect sizes can be plotted in descending order
example.df$Author<-reorder(example.df$Author, example.df$d, FUN=mean)

...然后是情节（没有任何coord_flip() usage):

p <- ggplot(example.df, aes(y = Author, x = d, xmin = ci.low, xmax = ci.high, shape=Gender)) +
geom_point() +
geom_errorbarh(height = .1) +
scale_x_continuous(limits=c(-2,2),breaks=c(-2,-1.5,-1,-0.5,0,.5,1,1.5,2))+
geom_vline(xintercept=0, color="grey60",linetype="dashed")+
facet_grid(Sport ~ ., scales = "free", space = "free") +
theme_bw() +
theme(strip.text.y = element_text(angle = 0))
p

非常好——感谢所有建议并帮助解决这个问题！