R ggplot geom_text_repel: duplicate colliding label problem

Question

This question uses the public data and code from another question

I am trying to add labels to my map. When I use geom_text, each label correctly appears once but collided (right side). To avoid collision, I am using geom_text_repel (The stick and text make it look cleaner) but when I use it the labels appear multiple times (left side) as you can see in my picture. Does anyone know what may be the issue? I tried a inner join instead of a left join but that did not work so I tried manipulating the options in geom_text_repel with no success. Thanks in advance for any assistance you can provide.

I checked here and here for assistance but still the issue occurs.

library(ggplot2)
library(sf)
library(tidyverse)
library(ggrepel)


map7 <- read_sf("england_ct_1991.shp")
totalPrices <- read_csv("england_ct_1991.csv")

new <- totalPrices %>%
 group_by(name) %>%
 mutate(price = rnorm(1)) %>% 
distinct(name, price)
new

map7 %>%
 left_join(new) %>%
 ggplot() +
 geom_sf(aes(fill = price),color="black")

 cnames <- aggregate(cbind(x, y, price) ~ name, data=totalPrices, 
                 FUN=function(x)mean(range(x)))
 head(cnames)
 # cnames code is from [here][4]


map7 %>%
 left_join(cnames) %>%
ggplot() +
 geom_sf(aes(fill = price),color="black")+
 theme(axis.text.x = element_blank(),
    axis.text.y = element_blank(),
    axis.ticks = element_blank(),
    axis.title.y=element_blank(),
    axis.title.x=element_blank(),
    rect = element_blank(),
    panel.background = element_blank()) +
  scale_fill_gradient(low = "white", high = "black", na.value = "red", 
                  guide = 'colorbar', aesthetics = 'fill') +
  #geom_text( aes(x, y, label = name)) +
  geom_text_repel( aes(x, y, label = name, geometry = geometry), stat = "sf_coordinates",
      show.legend=FALSE, size = 3) 

Answer 1

Because there are multiple sets of geometry within the same name. One fix of this is to keep one name only for those multiple sets of geometry. A quick solution is to keep the first name and replace the rest with NA or " ".

map7 %>%
  left_join(cnames) %>%
  mutate(name_1 = ifelse(row_number() == 1, name, NA), .by = name) %>%
  ggplot() +
  geom_sf(aes(fill = price), color = "black") +
  theme(
    axis.text.x = element_blank(),
    axis.text.y = element_blank(),
    axis.ticks = element_blank(),
    axis.title.y = element_blank(),
    axis.title.x = element_blank(),
    rect = element_blank(),
    panel.background = element_blank()
  ) +
  scale_fill_gradient(
    low = "white", high = "black", na.value = "red",
    guide = "colorbar", aesthetics = "fill"
  ) +
  geom_text_repel(aes(x, y, label = name_1, geometry = geometry),
    stat = "sf_coordinates",
    show.legend = FALSE, size = 3
  )

Alternatively, we could manually choose which name to use.