I am plotting a set of Odds Ratios for 18 variables which fall within 3 groups.

I would like the variables to be ordered by group, as well as coloured by group. So far I have managed to colour the points by group - but cannot figure out how to stop the variables from plotting alphabetically.

My script so far:

ggplot(pfhist_df, aes(x = boxOdds, y = groups))   
  geom_errorbarh(aes(xmin = boxCILow, xmax = boxCIHigh), size = .5, height = .2, color = "gray50")  
  geom_point(aes(colour = groups, shape = groups), size = 3.5 )  
  geom_vline(aes(xintercept = 1), linetype = 2)  
  scale_shape_manual(values = rep(15, 5))  
  scale_fill_manual(values = rep(c("#ffffff00", "#f0f0f090"), 9)[-1],
                    guide = "none")  
  scale_x_log10()  
  #coord_cartesian(xlim = c(0.01, 100))  
  facet_grid(labels~., switch = "y")  
  theme_bw()  
  theme(panel.spacing.y = unit(0, "points"),
        panel.border = element_blank(),
        axis.text.y = element_blank(),
        plot.title = element_text(hjust = 0.5),
        axis.ticks.length.y = unit(0, "points"),
        strip.text.y.left = element_text(angle = 0),
        strip.background.y = element_blank(),
        strip.placement = "outside",
        axis.line = element_line()
  )   
  ylab("")   
  xlab("Odds Ratio")   
  ggtitle("Recent Exposure to Plasmodium falciparum") 

Which produces:

I have tried by calling factor(groups) but this does not work - it simply gives me another legend.

My data:

pfhist_df <- data.frame(labels = c("Travel time to hospital > 10h",
                                   "Travel time to hospital > 18h",
                                   "Travel time to hospital > 28h",
                                   "Ethnicity: Dusun",
                                   "Ethnicity: Rungus",
                                   "Ethnicity: Sungoi",
                                   "Wealth: quartile 2", 
                                   "Wealth: quartile 3",
                                   "Wealth: quartile 4",
                                   "Occupation: student", 
                                   "Previously diagnosed with malaria", 
                                   "Elevation: 13 - 30m", 
                                   "Elevation > 213m", 
                                   "Travel time to clinic >7h", 
                                   "Travel time to clinic >10h", 
                                   "Head of household educated", 
                                   "Spend more than 3h outside daily", 
                                   "Travel to forest"), 
                        groups = c("Household", 
                                   "Household",
                                   "Household", 
                                   "Demographics",
                                   "Demographics",
                                   "Demographics",
                                   "Demographics",
                                   "Demographics",
                                   "Demographics",
                                   "Demographics",
                                   "Behaviour", 
                                   "Household",
                                   "Household",
                                   "Household",
                                   "Household",
                                   "Demographics",
                                   "Behaviour",
                                   "Behaviour"),
                        boxOdds = c(1.34,
                                    1.58,
                                    2.33,
                                    1.89,
                                    1.57,
                                    1.46,
                                    0.8, 
                                    0.69,
                                    0.48,
                                    0.43, 
                                    1.6, 
                                    1.26, 
                                    0.54, 
                                    1.22, 
                                    1.32,
                                    0.79, 
                                    1.57, 
                                    1.4),
                        boxCILow = c(1.09, 
                                     1.27, 
                                     1.83, 
                                     1.43, 
                                     1.21, 
                                     1.06, 
                                     0.67, 
                                     0.56, 0.38, 0.28, 1.36, 1.03, 0.4, 1.01, 1.08, 0.72, 1.11, 1.12),
                        boxCIHigh = c(1.64, 1.96, 2.95, 2.49, 2.05, 2.29, 0.99, 0.85, 0.6, 0.65, 
                                      1.88, 1.54, 0.72, 1.48, 1.63, 0.87, 2.23, 1.75))
                                   
pfhist_df$groups <- as.factor(pfhist_df$groups)                                 

CodePudding user response：

What you could do is remove the facet_grid and use fct_reorder to reorder the y labels based on your groups like this:

pfhist_df$group <- factor(x = pfhist_df$group, levels = unique(pfhist_df$groups))
library(forcats)
library(ggplot2)
ggplot(pfhist_df, aes(x = boxOdds, y = fct_reorder(labels, groups)))   
          geom_errorbarh(aes(xmin = boxCILow, xmax = boxCIHigh), size = .5, height = .2, color = "gray50")  
          geom_point(aes(colour = groups, shape = groups), size = 3.5 )  
          geom_vline(aes(xintercept = 1), linetype = 2)  
          scale_shape_manual(values = rep(15, 5))  
          scale_fill_manual(values = rep(c("#ffffff00", "#f0f0f090"), 9)[-1],
                            guide = "none")  
          scale_x_log10()  
          theme_bw()  
          ylab("")   
          xlab("Odds Ratio")   
          ggtitle("Recent Exposure to Plasmodium falciparum") 

^{Created on 2022-07-22 by the}