Estimating Howling Cow

This is the code that goes along with creating a confidence inteval for the howling cow exercise we went through in class.

Packages

library(tidyverse)

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ℹ Use the conflicted package (<http://conflicted.r-lib.org/>) to force all conflicts to become errors

library(tidymodels)

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• Learn how to get started at https://www.tidymodels.org/start/

The Data

cow_data <- tibble(
  survey = c((rep("Eat" , 37)), rep("No" , 63)))

The Process

set.seed(12345)

boot_df <- cow_data |>
  specify(response = survey, success = "Eat") |>
  generate(reps = 10000, type = "bootstrap") |>
  calculate(stat = "prop")

The Graph

boot_df |>
  ggplot(
    aes(x = stat)
  ) + 
  geom_density(fill = "gray") +
  labs(title = "Bootstrap distribution",
       y = "")

The Calculation

boot_df |>
  summarize(lower = quantile(stat, 0.025),
            upper = quantile(stat, 0.975))

# A tibble: 1 × 2
  lower upper
  <dbl> <dbl>
1  0.28  0.47