learn_measurement_error

source

learn_measurement_error(n=4000, beta=1.0, noise_x=1.0, seed=0)

Show classical measurement-error attenuation: noise in the regressor biases OLS to zero.

Simulates y = beta*x_true + e but regresses on a noisy observation x_obs = x_true + u. The OLS slope is attenuated toward zero by the reliability ratio var(x_true) / (var(x_true) + var(u)).

Parameters

Name Type Description Default
n int Sample size. 4000
beta float True slope on the (unobserved) x_true. 1.0
noise_x float Standard deviation of the measurement noise added to x_true (drives the attenuation). 1.0
seed int Random seed. 0

Returns

Name Type Description
SandboxResult df (naive vs true slope), fig, summary and topic.

Examples

This sandbox simulates its own data, so the call needs no DataFrame:

import expdpy as ex

res = ex.learn_measurement_error()
res.fig