compare rasmussen polling average vs average of all other polls

rasmussen_v_other_approval.R

library(tidyverse)
library(zoo)

trump_approve <- read_csv("https://projects.fivethirtyeight.com/polls-page/president_approval_polls.csv")

trump_approve <- trump_approve %>% 
  mutate("date" = mdy(end_date)) %>% 
  dplyr::select(pollster,
                date, 
                "approve" = yes,
                "disapprove" = no) %>% 
  arrange(date) %>%
  mutate(Rasmussen = ifelse(pollster == 'Rasmussen Reports/Pulse Opinion Research',approve-disapprove,NA),
         Other = ifelse(pollster != 'Rasmussen Reports/Pulse Opinion Research',approve-disapprove,NA)) 

trump_approve <- trump_approve %>%
  group_by(date) %>%
  summarise(Rasmussen = mean(Rasmussen,na.rm=T),
            Other = mean(Other,na.rm=T)) %>%
  mutate(average_other = rollapply(Other,60,FUN=mean,partial=T,na.rm=T),
         average_rasmussen = rollapply(Rasmussen,60,FUN=mean,partial=T,na.rm=T))

ggplot(trump_approve, aes(x=date)) +
  geom_line(aes(y=average_other,col='Average')) +
  geom_line(aes(y=average_rasmussen,col='Rasmussen')) +
  labs(x='Date',y='',subtitle="Trump, average approval rating") +
  theme_minimal() + 
  theme(legend.position = 'top',legend.justification = 'left',
        panel.grid.minor = element_blank()) +
  scale_color_brewer(name='',palette='Dark2')

ggplot(trump_approve, aes(x=date)) +
  geom_line(aes(y=average_rasmussen - average_other)) +
  labs(x='Date',y='',subtitle="Trump, average approval rating\nRasmussen minus other pollsters") +
  scale_y_continuous(breaks=seq(0,20,2)) +
  theme_minimal() + 
  theme(legend.position = 'top',legend.justification = 'left',
        panel.grid.minor = element_blank()) +
  scale_color_brewer(name='',palette='Dark2')