Files
OpenBB/openbb_terminal/econometrics/regression_model.py
Henrique Joaquim 386fbfa9ca Fix #3511 (#3597)
* added dot verification

* typos
2022-11-26 13:24:33 -05:00

571 lines
20 KiB
Python

"""Regression Model"""
__docformat__ = "numpy"
import logging
import os
import warnings
from typing import Any, Dict, List, Tuple
import pandas as pd
import statsmodels
import statsmodels.api as sm
from linearmodels import PooledOLS
from linearmodels.panel import (
BetweenOLS,
FirstDifferenceOLS,
PanelOLS,
RandomEffects,
compare,
)
from pandas import DataFrame
from statsmodels.api import add_constant
from statsmodels.stats.api import het_breuschpagan
from statsmodels.stats.diagnostic import acorr_breusch_godfrey
from statsmodels.stats.stattools import durbin_watson
from openbb_terminal.decorators import log_start_end
from openbb_terminal.econometrics.econometrics_helpers import get_datasets
from openbb_terminal.helper_funcs import export_data
from openbb_terminal.rich_config import console
logger = logging.getLogger(__name__)
def get_regressions_results(
Y: pd.DataFrame,
X: pd.DataFrame,
regression_type: str = "OLS",
entity_effects: bool = False,
time_effects: bool = False,
) -> Any:
"""Based on the regression type, this function decides what regression to run.
Parameters
----------
Y: pd.DataFrame
Dataframe containing the dependent variable.
X: pd.DataFrame
Dataframe containing the independent variables.
regression_type: str
The type of regression you wish to execute.
entity_effects: bool
Whether to apply Fixed Effects on entities.
time_effects: bool
Whether to apply Fixed Effects on time.
Returns
-------
Any
A regression model
Examples
--------
>>> from openbb_terminal.sdk import openbb
>>> df = openbb.econometrics.load("wage_panel")
>>> df = df.set_index(["nr","year"])
>>> X = df[["exper","educ","union"]]
>>> Y = df["lwage"]
>>> pooled_ols_model = openbb.econometrics.panel(Y,X,"POLS")
>>> print(pooled_ols_model.summary)
PooledOLS Estimation Summary
================================================================================
Dep. Variable: lwage R-squared: 0.1634
Estimator: PooledOLS R-squared (Between): 0.1686
No. Observations: 4360 R-squared (Within): 0.1575
Date: Sun, Nov 13 2022 R-squared (Overall): 0.1634
Time: 13:04:02 Log-likelihood -3050.4
Cov. Estimator: Unadjusted
F-statistic: 283.68
Entities: 545 P-value 0.0000
Avg Obs: 8.0000 Distribution: F(3,4356)
Min Obs: 8.0000
Max Obs: 8.0000 F-statistic (robust): 283.68
P-value 0.0000
Time periods: 8 Distribution: F(3,4356)
Avg Obs: 545.00
Min Obs: 545.00
Max Obs: 545.00
Parameter Estimates
==============================================================================
Parameter Std. Err. T-stat P-value Lower CI Upper CI
------------------------------------------------------------------------------
const -0.0308 0.0620 -0.4965 0.6196 -0.1523 0.0908
exper 0.0561 0.0028 20.220 0.0000 0.0507 0.0616
educ 0.1080 0.0045 24.034 0.0000 0.0992 0.1168
union 0.1777 0.0172 10.344 0.0000 0.1441 0.2114
==============================================================================
"""
regressions = {
"OLS": lambda: get_ols(Y, X),
"POLS": lambda: get_pols(Y, X),
"RE": lambda: get_re(Y, X),
"BOLS": lambda: get_bols(Y, X),
"FE": lambda: get_fe(Y, X, entity_effects, time_effects),
"FDOLS": lambda: get_fdols(Y, X),
}
if regression_type in regressions:
return regressions[regression_type]()
return console.print(f"{regression_type} is not an option.")
def get_regression_data(
regression_variables: List[tuple],
data: Dict[str, pd.DataFrame],
regression_type: str = "",
) -> Tuple[DataFrame, Any, List[Any]]:
"""This function creates a DataFrame with the required regression data as
well sets up the dependent and independent variables.
Parameters
----------
regression_variables : list
The regressions variables entered where the first variable is
the dependent variable.
data : dict
A dictionary containing the datasets.
regression_type: str
The type of regression that is executed.
Returns
-------
Tuple[DataFrame, Any, List[Any]]
The dataset used,
Dependent variable,
Independent variable,
OLS model.
"""
datasets = get_datasets(data)
regression = {}
independent_variables = []
dependent_variable = None
for variable in regression_variables:
column, dataset = datasets[variable].keys()
regression[f"{dataset}.{column}"] = data[dataset][column]
if variable == regression_variables[0]:
dependent_variable = f"{dataset}.{column}"
elif variable in regression_variables[1:]:
independent_variables.append(f"{dataset}.{column}")
regression_df = pd.DataFrame(regression)
nan_values = regression_df.isnull().sum().sum()
if nan_values > 0:
regression_df = regression_df.dropna(how="any", axis="index")
if regression_df.empty:
console.print(
f"The resulting DataFrame only consists of NaN values. This is usually due to an index "
f"mismatch. Therefore, no {regression_type} regression can be performed. Consider revisiting your "
"dataset(s) and adjust accordingly."
)
else:
console.print(
f"The resulting DataFrame has {nan_values} NaN values. This is usually due to "
f"an index mismatch. Rows that contain NaNs are dropped to be able to perform the {regression_type} "
f"regression. Consider revisiting your dataset(s) and adjust accordingly."
)
return regression_df, dependent_variable, independent_variables
@log_start_end(log=logger)
def get_ols(Y: pd.DataFrame, X: pd.DataFrame) -> Any:
"""Performs an OLS regression on timeseries data. [Source: Statsmodels]
Parameters
----------
Y: pd.DataFrame
Dependent variable series.
X: pd.DataFrame
Dataframe of independent variables series.
Returns
-------
statsmodels.regression.linear_model.RegressionResultsWrapper
Regression model wrapper from statsmodels.
Examples
--------
>>> from openbb_terminal.sdk import openbb
>>> df = openbb.econometrics.load("wage_panel")
>>> OLS_model = openbb.econometrics.ols(df["lwage"], df[["educ", "exper", "expersq"]])
>>> print(OLS_model.summary())`
OLS Regression Results
=======================================================================================
Dep. Variable: lwage R-squared (uncentered): 0.920
Model: OLS Adj. R-squared (uncentered): 0.919
Method: Least Squares F-statistic: 1.659e+04
Date: Thu, 10 Nov 2022 Prob (F-statistic): 0.00
Time: 15:28:11 Log-Likelihood: -3091.3
No. Observations: 4360 AIC: 6189.
Df Residuals: 4357 BIC: 6208.
Df Model: 3
Covariance Type: nonrobust
==============================================================================
coef std err t P>|t| [0.025 0.975]
------------------------------------------------------------------------------
educ 0.0986 0.002 39.879 0.000 0.094 0.103
exper 0.1018 0.009 10.737 0.000 0.083 0.120
expersq -0.0034 0.001 -4.894 0.000 -0.005 -0.002
==============================================================================
Omnibus: 1249.642 Durbin-Watson: 0.954
Prob(Omnibus): 0.000 Jarque-Bera (JB): 9627.436
Skew: -1.152 Prob(JB): 0.00
Kurtosis: 9.905 Cond. No. 86.4
==============================================================================
Notes:
[1] R² is computed without centering (uncentered) since the model does not contain a constant.
[2] Standard Errors assume that the covariance matrix of the errors is correctly specified.
"""
if X.empty or Y.empty:
model = None
else:
with warnings.catch_warnings(record=True) as warning_messages:
model = sm.OLS(Y, X).fit()
if len(warning_messages) > 0:
console.print("Warnings:")
for warning in warning_messages:
console.print(f"[red]{warning.message}[/red]".replace("\n", ""))
return model
@log_start_end(log=logger)
def get_pols(Y: pd.DataFrame, X: pd.DataFrame) -> Any:
"""PooledOLS is just plain OLS that understands that various panel data structures.
It is useful as a base model. [Source: LinearModels]
Parameters
----------
regression_variables : list
The regressions variables entered where the first variable is
the dependent variable.
data : dict
A dictionary containing the datasets.
Returns
-------
Tuple[DataFrame, Any, List[Any], Any]
The dataset used,
Dependent variable,
Independent variable,
PooledOLS model
"""
if Y.empty or X.empty:
model = None
else:
with warnings.catch_warnings(record=True) as warning_messages:
exogenous = add_constant(X)
model = PooledOLS(Y, exogenous).fit()
if len(warning_messages) > 0:
console.print("Warnings:")
for warning in warning_messages:
console.print(f"[red]{warning.message}[/red]".replace("\n", ""))
return model
@log_start_end(log=logger)
def get_re(Y: pd.DataFrame, X: pd.DataFrame) -> Any:
"""The random effects model is virtually identical to the pooled OLS model except that is accounts for the
structure of the model and so is more efficient. Random effects uses a quasi-demeaning strategy which
subtracts the time average of the within entity values to account for the common shock. [Source: LinearModels]
Parameters
----------
regression_variables : list
The regressions variables entered where the first variable is
the dependent variable.
data : dict
A dictionary containing the datasets.
Returns
-------
Tuple[DataFrame, Any, List[Any], Any]
The dataset used,
Dependent variable,
Independent variable,
RandomEffects model
"""
if X.empty or Y.empty:
model = None
else:
with warnings.catch_warnings(record=True) as warning_messages:
exogenous = add_constant(X)
model = RandomEffects(Y, exogenous).fit()
if len(warning_messages) > 0:
console.print("Warnings:")
for warning in warning_messages:
console.print(f"[red]{warning.message}[/red]".replace("\n", ""))
return model
@log_start_end(log=logger)
def get_bols(Y: pd.DataFrame, X: pd.DataFrame) -> Any:
"""The between estimator is an alternative, usually less efficient estimator, can can be used to
estimate model parameters. It is particular simple since it first computes the time averages of
y and x and then runs a simple regression using these averages. [Source: LinearModels]
Parameters
----------
regression_variables : list
The regressions variables entered where the first variable is
the dependent variable.
data : dict
A dictionary containing the datasets.
Returns
-------
Tuple[DataFrame, Any, List[Any], Any]
The dataset used,
Dependent variable,
Independent variable,
Between OLS model.
"""
if Y.empty or X.empty:
model = None
else:
with warnings.catch_warnings(record=True) as warning_messages:
exogenous = add_constant(X)
model = BetweenOLS(Y, exogenous).fit()
if len(warning_messages) > 0:
console.print("Warnings:")
for warning in warning_messages:
console.print(f"[red]{warning.message}[/red]".replace("\n", ""))
return model
@log_start_end(log=logger)
def get_fe(
Y: pd.DataFrame,
X: pd.DataFrame,
entity_effects: bool = False,
time_effects: bool = False,
) -> Any:
"""When effects are correlated with the regressors the RE and BE estimators are not consistent.
The usual solution is to use Fixed Effects which are called entity_effects when applied to
entities and time_effects when applied to the time dimension. [Source: LinearModels]
Parameters
----------
regression_variables : list
The regressions variables entered where the first variable is
the dependent variable.
data : dict
A dictionary containing the datasets.
entity_effects : bool
Whether to include entity effects
time_effects : bool
Whether to include time effects
Returns
-------
Tuple[DataFrame, Any, List[Any], Any]
The dataset used,
Dependent variable,
Independent variable,
PanelOLS model with Fixed Effects
"""
if X.empty or Y.empty:
model = None
else:
with warnings.catch_warnings(record=True) as warning_messages:
exogenous = add_constant(X)
model = PanelOLS(
Y, exogenous, entity_effects=entity_effects, time_effects=time_effects
).fit()
if len(warning_messages) > 0:
console.print("Warnings:")
for warning in warning_messages:
console.print(f"[red]{warning.message}[/red]".replace("\n", ""))
return model
@log_start_end(log=logger)
def get_fdols(Y: pd.DataFrame, X: pd.DataFrame) -> Any:
"""First differencing is an alternative to using fixed effects when there might be correlation.
When using first differences, time-invariant variables must be excluded. Additionally,
only one linear time-trending variable can be included since this will look like a constant.
This variable will soak up all time-trends in the data, and so interpretations of
these variable can be challenging. [Source: LinearModels]
Parameters
----------
regression_variables : list
The regressions variables entered where the first variable is
the dependent variable.
data : dict
A dictionary containing the datasets.
Returns
-------
Tuple[DataFrame, Any, List[Any], Any]
The dataset used,
Dependent variable,
Independent variable,
First Difference OLS model
"""
if X.empty or Y.empty:
model = None
else:
with warnings.catch_warnings(record=True) as warning_messages:
model = FirstDifferenceOLS(Y, X).fit()
if len(warning_messages) > 0:
console.print("Warnings:")
for warning in warning_messages:
console.print(f"[red]{warning.message}[/red]".replace("\n", ""))
return model
@log_start_end(log=logger)
def get_comparison(regressions: Dict, export: str = ""):
"""Compare regression results between Panel Data regressions.
Parameters
----------
regressions : Dict
Dictionary with regression results.
export : str
Format to export data
Returns
-------
dict
Returns a PanelModelComparison which shows an overview of the different regression results.
"""
comparison = {}
for regression_type, data in regressions.items():
if regression_type == "OLS":
continue
if data["model"]:
comparison[regression_type] = data["model"]
if not comparison:
# When the dictionary is empty, it means no Panel regression
# estimates are available and thus the function will have no output
return console.print(
"No Panel regression estimates available. Please use the "
"command 'panel' before using this command."
)
comparison_result = compare(comparison)
console.print(comparison_result)
if export:
results_as_html = comparison_result.summary.tables[0].as_html()
df = pd.read_html(results_as_html, header=0, index_col=0)[0]
export_data(
export,
os.path.dirname(os.path.abspath(__file__)),
"regressions_compare",
df,
)
return comparison_result
@log_start_end(log=logger)
def get_dwat(
model: statsmodels.regression.linear_model.RegressionResultsWrapper,
) -> float:
"""Calculate test statistics for Durbin Watson autocorrelation
Parameters
----------
model : statsmodels.regression.linear_model.RegressionResultsWrapper
Previously fit statsmodels OLS.
Returns
-------
float
Test statistic of the Durbin Watson test.
Notes
------
When using chart = True, the dependent variable in the regression must be passed to view the residuals
Example
-------
>>> from openbb_terminal.sdk import openbb
>>> df = openbb.econometrics.load("wage_panel")
>>> Y, X = df["lwage"], df[["exper","educ"]]
>>> model = openbb.econometrics.ols(Y,X)
>>> durbin_watson_value = openbb.econometrics.dwat(model)
0.96
"""
# Durbin Watson test: The test statistic is approximately equal to 2*(1-r) where r is the
# sample autocorrelation of the residuals. Thus, for r == 0, indicating no serial correlation,
# the test statistic equals 2. This statistic will always be between 0 and 4. The closer
# to 0 the statistic, the more evidence for positive serial correlation. The closer to 4,
# the more evidence for negative serial correlation.
result = durbin_watson(model.resid)
return round(result, 2)
@log_start_end(log=logger)
def get_bgod(model: pd.DataFrame, lags: int = 3) -> Tuple[float, float, float, float]:
"""Calculate test statistics for autocorrelation
Parameters
----------
model : OLS Model
OLS model that has been fit.
lags : int
The amount of lags.
Returns
-------
pd.DataFrame
Test results from the Breusch-Godfrey Test
"""
lm_stat, p_value, f_stat, fp_value = acorr_breusch_godfrey(model, nlags=lags)
return pd.DataFrame(
[lm_stat, p_value, f_stat, fp_value],
index=["lm-stat", "p-value", "f-stat", "fp-value"],
)
@log_start_end(log=logger)
def get_bpag(
model: statsmodels.regression.linear_model.RegressionResultsWrapper,
) -> pd.DataFrame:
"""Calculate test statistics for heteroscedasticity
Parameters
----------
model : OLS Model
Model containing residual values.
Returns
-------
pd.DataFrame
Test results from the Breusch-Pagan Test
"""
lm_stat, p_value, f_stat, fp_value = het_breuschpagan(model.resid, model.model.exog)
return pd.DataFrame(
[lm_stat, p_value, f_stat, fp_value],
index=["lm-stat", "p-value", "f-stat", "fp-value"],
)