Nokta tahminlerinin bağıl hatası

R'de Örnekleme

Richie Cotton

Data Evangelist at DataCamp

Örneklem satır sayısıdır

coffee_ratings %>% 
  slice_sample(n = 300) %>% 
  nrow()
300
coffee_ratings %>% 
  slice_sample(prop = 0.25) %>% 
  nrow()
334
R'de Örnekleme

Çeşitli örneklem büyüklükleri

coffee_ratings %>% 
  summarize(mean_points = mean(total_cup_points)) %>% 
  pull(mean_points)

82.15
coffee_ratings %>% 
  slice_sample(n = 10) %>% 
  summarize(mean_points = mean(total_cup_points)) %>% 
  pull(mean_points)
82.82
coffee_ratings %>% 
  slice_sample(n = 100) %>% 
  summarize(mean_points = mean(total_cup_points)) %>% 
  pull(mean_points)
82.02
coffee_ratings %>% 
  slice_sample(n = 1000) %>% 
  summarize(mean_points = mean(total_cup_points)) %>% 
  pull(mean_points)
82.16
R'de Örnekleme

Bağıl hatalar

Ana kütle parametresi

population_mean <- coffee_ratings %>% 
  summarize(mean_points = mean(total_cup_points)) %>% 
  pull(mean_points)

Nokta tahmini

sample_mean <- coffee_ratings %>% 
  slice_sample(n = sample_size) %>% 
  summarize(mean_points = mean(total_cup_points)) %>% 
  pull(mean_points)

Yüzde olarak bağıl hata

100 * abs(population_mean - sample_mean) / population_mean
R'de Örnekleme

Bağıl hata ve örneklem büyüklüğü

ggplot(errors, aes(sample_size, relative_error)) +
  geom_line() +
  geom_smooth(method = "loess")

Örneklem büyüklüğüne göre bağıl hata saçılım grafiği.

R'de Örnekleme

Haydi pratik yapalım!

R'de Örnekleme

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