Relatieve fout van puntschattingen

Steekproeven in Python

James Chapman

Curriculum Manager, DataCamp

Steekproefgrootte is aantal rijen

len(coffee_ratings.sample(n=300))

len(coffee_ratings.sample(frac=0.25))

coffee_ratings['total_cup_points'].mean()

82.15120328849028

coffee_ratings.sample(n=10)['total_cup_points'].mean()

83.027

coffee_ratings.sample(n=100)['total_cup_points'].mean()

82.4897

coffee_ratings.sample(n=1000)['total_cup_points'].mean()

82.1186

Populatieparameter:

population_mean = coffee_ratings['total_cup_points'].mean()

Puntschatting:

sample_mean = coffee_ratings.sample(n=sample_size)['total_cup_points'].mean()

Relatieve fout als percentage:

rel_error_pct = 100 * abs(population_mean-sample_mean) / population_mean

import matplotlib.pyplot as plt
errors.plot(x="sample_size", 
            y="relative_error", 
            kind="line")
plt.show()

Eigenschappen:

Lijngrafiek van relatieve fout versus steekproefgrootte.

Steekproeven in Python