import expdpy as ex
res = ex.learn_correlated_random_effects()
res.figlearn_correlated_random_effects
Show the Mundlak (correlated random effects) device recovering the fixed-effects slope.
The CRE model adds each unit’s time-mean of the regressor to a random-effects specification. Its coefficient on the original x then equals the within (fixed-effects) estimate, and a Wald test on the added means is the Mundlak (Hausman-equivalent) test.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
| n_units | int | Panel dimensions. | 60 |
| n_periods | int | Panel dimensions. | 60 |
| beta | float | True within-unit slope. | 1.0 |
| unit_effect_corr | float | Correlation between x and the unit effect. |
0.8 |
| seed | int | Random seed. | 0 |
Returns
| Name | Type | Description |
|---|---|---|
| SandboxResult | df (CRE-within vs plain FE vs true slope), fig, summary and topic. |
Examples
This sandbox simulates its own panel, so the call needs no DataFrame: