Diagnostic

Andreas Bender

2018-10-06

library(magrittr)
library(tidyr)
library(purrr)
library(dplyr)
library(coalitions)
library(ggplot2)
theme_set(theme_bw())

temp <- scrape_wahlrecht() %>% slice(1) %>% collapse_parties() %>% unnest()

## Warning: 1 failed to parse.

## Warning: 1 failed to parse.

temp %<>%
    mutate(
        respondents = 1000L,
        percent  = c(36, 28, 7, 6, 9, 9, 5),
        votes    = respondents * percent/100) %>%
    nest(party:votes, .key=survey)

set.seed(29072017)
draws <- map(temp$survey, draw_from_posterior, nsim=1e4, correction=0.01) %>%
    flatten_df()
    draws_long <- gather(draws, party, percent, cdu:others) %>%
        group_by(party) %>%
        mutate(sim = row_number()) %>% ungroup()

ggplot(draws_long, aes(x=party, y=percent)) +
    geom_boxplot() +
    geom_hline(yintercept = 0.05, lty=2, col=2)

## chains
ggplot(draws_long, aes(x=sim, y=percent)) +
    geom_path() +
    geom_hline(yintercept = 0.05, lty=2, col=2) +
    facet_wrap(~party, nrow=2)

draws_long %>%
    group_by(party) %>%
    summarize(entryprob = sum(percent >= 0.05)/n())

## # A tibble: 7 x 2
##   party  entryprob
##   <chr>      <dbl>
## 1 afd        1    
## 2 cdu        1    
## 3 fdp        0.874
## 4 greens     0.988
## 5 left       1    
## 6 others     0.493
## 7 spd        1