def test_manova_no_formula_no_hypothesis():
# Same as previous test only skipping formula interface
exog = add_constant(pd.get_dummies(X[['Loc']], drop_first=True))
endog = X[['Basal', 'Occ', 'Max']]
mod = MANOVA(endog, exog)
r = mod.mv_test()
assert isinstance(r, MultivariateTestResults)
def __init__(self):
data = heart.load()
endog = np.log10(data.endog)
exog = add_constant(data.exog)
self.mod1 = emplikeAFT(endog, exog, data.censors)
self.res1 = self.mod1.fit()
self.res2 = AFTRes()
def test_forecast(self):
end = len(self.true['data']['consump'])+15-1
exog = add_constant(self.true['forecast_data']['m2'])
assert_almost_equal(
self.result.predict(end=end, exog=exog)[0],
self.true['forecast'], 3
)
def test_multiple_constraints():
endog = dta['infl']
exog = add_constant(dta[['m1', 'unemp', 'cpi']])
constraints = [
'm1 + unemp = 1',
'cpi = 0',
]
mod = RecursiveLS(endog, exog, constraints=constraints)
res = mod.fit()
# See tests/results/test_rls.do
desired = [-0.7001083844336, -0.0018477514060, 1.0018477514060, 0]
assert_allclose(res.params, desired, atol=1e-10)
# See tests/results/test_rls.do
desired = [.4699552366, .0005369357, .0005369357, 0]
assert_allclose(res.bse[0], desired[0], atol=1e-1)
assert_allclose(res.bse[1:-1], desired[1:-1], atol=1e-4)
# See tests/results/test_rls.do
desired = -534.4292052931121
# Note that to compute what Stata reports as the llf, we need to use a
# different denominator for estimating the scale, and then compute the
# llf from the alternative recursive residuals
scale_alternative = np.sum((
res.standardized_forecasts_error[0, 1:] *
res.filter_results.obs_cov[0, 0]**0.5)**2) / mod.nobs
llf_alternative = np.log(norm.pdf(res.resid_recursive, loc=0,
scale=scale_alternative**0.5)).sum()
assert_allclose(llf_alternative, desired)
def setup_class(cls):
data = heart.load()
endog = np.log10(data.endog)
exog = add_constant(data.exog)
cls.mod1 = emplikeAFT(endog, exog, data.censors)
cls.res1 = cls.mod1.fit()
cls.res2 = AFTRes()
def test_manova_no_formula():
# Same as previous test only skipping formula interface
exog = add_constant(pd.get_dummies(X[['Loc']], drop_first=True))
endog = X[['Basal', 'Occ', 'Max']]
mod = MANOVA(endog, exog)
intercept = np.zeros((1, 3))
intercept[0, 0] = 1
loc = np.zeros((2, 3))
loc[0, 1] = loc[1, 2] = 1
hypotheses = [('Intercept', intercept), ('Loc', loc)]
r = mod.mv_test(hypotheses)
assert_almost_equal(r['Loc']['stat'].loc["Wilks' lambda", 'Value'],
0.60143661, decimal=8)
assert_almost_equal(r['Loc']['stat'].loc["Pillai's trace", 'Value'],
0.44702843, decimal=8)
assert_almost_equal(r['Loc']['stat'].loc["Hotelling-Lawley trace",
'Value'],
0.58210348, decimal=8)
assert_almost_equal(r['Loc']['stat'].loc["Roy's greatest root", 'Value'],
0.35530890, decimal=8)
assert_almost_equal(r['Loc']['stat'].loc["Wilks' lambda", 'F Value'],
0.77, decimal=2)
assert_almost_equal(r['Loc']['stat'].loc["Pillai's trace", 'F Value'],
0.86, decimal=2)
assert_almost_equal(r['Loc']['stat'].loc["Hotelling-Lawley trace",
'F Value'],
0.75, decimal=2)
assert_almost_equal(r['Loc']['stat'].loc["Roy's greatest root", 'F Value'],
1.07, decimal=2)
assert_almost_equal(r['Loc']['stat'].loc["Wilks' lambda", 'Num DF'],
6, decimal=3)
assert_almost_equal(r['Loc']['stat'].loc["Pillai's trace", 'Num DF'],
6, decimal=3)
assert_almost_equal(r['Loc']['stat'].loc["Hotelling-Lawley trace",
'Num DF'],
6, decimal=3)
assert_almost_equal(r['Loc']['stat'].loc["Roy's greatest root", 'Num DF'],
3, decimal=3)
assert_almost_equal(r['Loc']['stat'].loc["Wilks' lambda", 'Den DF'],
16, decimal=3)
assert_almost_equal(r['Loc']['stat'].loc["Pillai's trace", 'Den DF'],
18, decimal=3)
assert_almost_equal(r['Loc']['stat'].loc["Hotelling-Lawley trace",
'Den DF'],
9.0909, decimal=4)
assert_almost_equal(r['Loc']['stat'].loc["Roy's greatest root", 'Den DF'],
9, decimal=3)
assert_almost_equal(r['Loc']['stat'].loc["Wilks' lambda", 'Pr > F'],
0.6032, decimal=4)
assert_almost_equal(r['Loc']['stat'].loc["Pillai's trace", 'Pr > F'],
0.5397, decimal=4)
assert_almost_equal(r['Loc']['stat'].loc["Hotelling-Lawley trace",
'Pr > F'],
0.6272, decimal=4)
assert_almost_equal(r['Loc']['stat'].loc["Roy's greatest root", 'Pr > F'],
0.4109, decimal=4)
def test_plots():
if not have_matplotlib:
raise SkipTest
exog = add_constant(dta[['m1', 'pop']])
mod = RecursiveLS(endog, exog)
res = mod.fit()
# Basic plot
fig = res.plot_recursive_coefficient()
plt.close(fig)
# Specific variable
fig = res.plot_recursive_coefficient(variables=['m1'])
plt.close(fig)
# All variables
fig = res.plot_recursive_coefficient(variables=[0, 'm1', 'pop'])
plt.close(fig)
# Basic plot
fig = res.plot_cusum()
plt.close(fig)
# Other alphas
for alpha in [0.01, 0.10]:
fig = res.plot_cusum(alpha=alpha)
plt.close(fig)
# Invalid alpha
assert_raises(ValueError, res.plot_cusum, alpha=0.123)
# Basic plot
fig = res.plot_cusum_squares()
plt.close(fig)
# Numpy input (no dates)
mod = RecursiveLS(endog.values, exog.values)
res = mod.fit()
# Basic plot
fig = res.plot_recursive_coefficient()
plt.close(fig)
# Basic plot
fig = res.plot_cusum()
plt.close(fig)
# Basic plot
fig = res.plot_cusum_squares()
plt.close(fig)
def __init__(self):
# Remove the regression coefficients from the parameters, since they
# will be estimated as part of the state vector
true = dict(results_sarimax.friedman2_mle)
exog = add_constant(true['data']['m2']) / 10.
true['mle_params_exog'] = true['params_exog'][:]
true['mle_se_exog'] = true['se_exog_oim'][:]
true['params_exog'] = []
true['se_exog'] = []
super(TestFriedmanStateRegression, self).__init__(
true, exog=exog, mle_regression=False
)
self.result = self.model.filter()
def __init__(self, true, exog=None, *args, **kwargs):
self.true = true
endog = np.r_[true['data']['consump']]
if exog is None:
exog = add_constant(true['data']['m2'])
kwargs.setdefault('simple_differencing', True)
kwargs.setdefault('hamilton_representation', True)
self.model = sarimax.SARIMAX(
endog, exog=exog, order=(1, 0, 1), *args, **kwargs
)
params = np.r_[true['params_exog'], true['params_ar'],
true['params_ma'], true['params_variance']]
self.model.update(params)
def setup_class(cls):
path = os.path.join(current_path, 'results', 'mar_filardo.csv')
cls.mar_filardo = pd.read_csv(path)
true = {
'params': np.r_[4.35941747, -1.6493936, 1.7702123, 0.9945672,
0.517298, -0.865888,
np.exp(-0.362469)**2,
0.189474, 0.079344, 0.110944, 0.122251],
'llf': -586.5718,
'llf_fit': -586.5718,
'llf_fit_em': -586.5718
}
endog = cls.mar_filardo['dlip'].iloc[1:].values
exog_tvtp = add_constant(
cls.mar_filardo['dmdlleading'].iloc[:-1].values)
super(TestFilardo, cls).setup_class(
true, endog, k_regimes=2, order=4, switching_ar=False,
exog_tvtp=exog_tvtp)
def wls(data, use_bayes=False):
""" Weighted least squares for peptides in protein.
Operates on sub data frames """
# Degenerate case, only one peptide
if data.shape[0] == 1:
return wls_degenerate(data)
y = data['meanC'].append(data['meanE']).values
if use_bayes:
w = data['bayesSDC'].append(data['bayesSDE']).values**2
else:
w = data['stdC'].append(data['stdE']).values**2
x = np.ones(data.shape[0]*2)
x[:data.shape[0]] = 0
mod_wls = sm.WLS(y, add_constant(x, prepend=False), weights=1./w)
res_wls = mod_wls.fit()
return (res_wls.params[0], res_wls.bse[0], res_wls.pvalues[0])
def setup_class(cls):
path = os.path.join(current_path, 'results', 'mar_filardo.csv')
cls.mar_filardo = pd.read_csv(path)
true = {
'params': np.r_[4.35941747, -1.6493936, 1.7702123, 0.9945672,
0.517298, -0.865888,
np.exp(-0.362469)**2,
0.189474, 0.079344, 0.110944, 0.122251],
'llf': -586.5718,
'llf_fit': -586.5718,
'llf_fit_em': -586.5718
}
endog = cls.mar_filardo['dlip'].iloc[1:].values
exog_tvtp = add_constant(
cls.mar_filardo['dmdlleading'].iloc[:-1].values)
super(TestFilardo, cls).setup_class(
true, endog, k_regimes=2, order=4, switching_ar=False,
exog_tvtp=exog_tvtp)
def _check_constant_params(a, has_const=False, use_const=True, rtol=1e-05,
atol=1e-08):
"""Helper func to interaction between has_const and use_const params.
has_const use_const outcome
--------- --------- -------
True True Confirm that a has constant; return a
False False Confirm that a doesn't have constant; return a
False True Confirm that a doesn't have constant; add constant
True False ValueError
"""
if all((has_const, use_const)):
if not _confirm_constant(a):
raise ValueError('Data does not contain a constant; specify'
' has_const=False')
k = a.shape[-1] - 1
elif not any((has_const, use_const)):
if _confirm_constant(a):
raise ValueError('Data already contains a constant; specify'
' has_const=True')
k = a.shape[-1]
elif not has_const and use_const:
# Also run a quick check to confirm that `a` is *not* ~N(0,1).
# In this case, constant should be zero. (exclude it entirely)
c1 = np.allclose(a.mean(axis=0), b=0., rtol=rtol, atol=atol)
c2 = np.allclose(a.std(axis=0), b=1., rtol=rtol, atol=atol)
if c1 and c2:
# TODO: maybe we want to just warn here?
raise ValueError('Data appears to be ~N(0,1). Specify'
' use_constant=False.')
# `has_constant` does checking on its own and raises VE if True
try:
a = add_constant(a, has_constant='raise')
except ValueError as e:
raise ValueError(
'X data already contains a constant; please specify'
' has_const=True'
) from e
k = a.shape[-1] - 1
else:
raise ValueError('`use_const` == False implies has_const is False.')
return k, a
def test_plots(close_figures):
exog = add_constant(dta[['m1', 'pop']])
mod = RecursiveLS(endog, exog)
res = mod.fit()
# Basic plot
try:
from pandas.plotting import register_matplotlib_converters
register_matplotlib_converters()
except ImportError:
pass
fig = res.plot_recursive_coefficient()
# Specific variable
fig = res.plot_recursive_coefficient(variables=['m1'])
# All variables
fig = res.plot_recursive_coefficient(variables=[0, 'm1', 'pop'])
# Basic plot
fig = res.plot_cusum()
# Other alphas
for alpha in [0.01, 0.10]:
fig = res.plot_cusum(alpha=alpha)
# Invalid alpha
assert_raises(ValueError, res.plot_cusum, alpha=0.123)
# Basic plot
fig = res.plot_cusum_squares()
# Numpy input (no dates)
mod = RecursiveLS(endog.values, exog.values)
res = mod.fit()
# Basic plot
fig = res.plot_recursive_coefficient()
# Basic plot
fig = res.plot_cusum()
# Basic plot
fig = res.plot_cusum_squares()
def test_plots(close_figures):
exog = add_constant(dta[['m1', 'pop']])
mod = RecursiveLS(endog, exog)
res = mod.fit()
# Basic plot
try:
from pandas.plotting import register_matplotlib_converters
register_matplotlib_converters()
except ImportError:
pass
fig = res.plot_recursive_coefficient()
# Specific variable
fig = res.plot_recursive_coefficient(variables=['m1'])
# All variables
fig = res.plot_recursive_coefficient(variables=[0, 'm1', 'pop'])
# Basic plot
fig = res.plot_cusum()
# Other alphas
for alpha in [0.01, 0.10]:
fig = res.plot_cusum(alpha=alpha)
# Invalid alpha
assert_raises(ValueError, res.plot_cusum, alpha=0.123)
# Basic plot
fig = res.plot_cusum_squares()
# Numpy input (no dates)
mod = RecursiveLS(endog.values, exog.values)
res = mod.fit()
# Basic plot
fig = res.plot_recursive_coefficient()
# Basic plot
fig = res.plot_cusum()
# Basic plot
fig = res.plot_cusum_squares()
def trend(x, time='time', detrend=False):
"""returns trend per year"""
from statsmodels.tools import add_constant
year = 3600 * 24 * 365.24 # slope is w.r.t. seconds
t = add_constant(x[time].values.astype('datetime64[s]').astype(float))
lsq = np.linalg.lstsq(t, x.squeeze())[0]
coords = [
c for c in set(x.coords) - {time}
if (x.coords[c].shape != ()) and (len(x.coords[c]) > 1)
]
if len(coords) == 1:
if detrend:
return xr.DataArray(x - t.dot(lsq),
coords=[x.time, x.coords[coords[0]]])
return xr.DataArray(lsq[1, :], coords=[x.coords[coords[0]]]) * year
elif len(coords) == 0:
return x - t.dot(lsq) if detrend else lsq[1] * year
else:
raise Exception('more than one additional coordinate')
def backwardElimination(input_matrix, output_array, significance_level=0.05):
data = add_constant(input_matrix)
candidate_variables = list(data.columns)
# >1 because we've added a 'const' column
while len(candidate_variables) > 1:
data = data.loc[:, candidate_variables]
regressor = sm.OLS(endog=output_array, exog=data).fit()
worst_index, p_value = max(enumerate(regressor.pvalues), key=itemgetter(1))
if p_value > significance_level:
print(f"Eliminating '{candidate_variables[worst_index]}' with p-value {p_value:.2}")
del candidate_variables[worst_index]
else:
print(f"Final variable selection: {candidate_variables[1:]}")
print(regressor.summary())
return data.loc[:, candidate_variables[1:]]
print("No significant correlation found for any variables")
return None
def computeForDay(self, strategy, timeSeriesTick, timeSeriesTrade):
timeSeriesReg = timeSeriesTick.resample(
str(int(self.resamplePeriod)) + "S"
).first()
timeSeriesReg = timeSeriesReg.fillna(method="pad")
timeTable = timeSeriesReg.to_frame()
timeTable["second"] = timeSeriesReg.index.astype(np.int64)
timeTable["second"] = (timeTable["second"] - timeTable["second"][0]) / math.pow(
10, 9
)
# self.betaSeries = pd.stats.ols.MovingOLS(y=timeTable['price'], x=timeTable['second'], window_type='rolling', window = self.period, intercept=True).beta
mod = RollingOLS(
timeTable["price"],
add_constant(timeTable["second"], prepend=False),
window=self.period,
)
self.betaSeries = mod.fit().params
return {"betaSeries": self.betaSeries}
def ols_fit_train(y_array,df,col_list):
'''
Takes df and string name of y column name in df, uses patsy_input_str to create string and inputs into feature matrix.
Outputs OLS fit summary.
'''
input_string = patsy_input_str(df,y_col_name)
# Create your feature matrix (X) and target vector (y)
y, X = patsy.dmatrices(input_string, data=df, return_type="dataframe")
#X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=.2, random_state=10)
# Create your model
model = sm.OLS(y_array, add_constant(df.loc[:,col_list]))
# Fit your model to your training set
fit = model.fit()
# Print summary statistics of the model's performance
return fit.summary()
def basic_logistic_regression(df,
cutoff,
col='pop_bin',
rand=0,
sig_only=False):
df = df.copy()
X, y = return_X_y_logistic(split_sample_combine(df, cutoff, col,
rand=rand))
X = standardize_X(X)
X_const = add_constant(X, prepend=True)
print("X_const\n", X_const)
print("Y\n", y)
logit_model = Logit(y, X_const).fit(solver='lbfgs',
skip_hessian=True,
max_iter=20000)
print(logit_model.summary())
return logit_model
def linear_regression(Y,
X,
multiple_X=1,
fix_nan=True,
alfa=False,
integrate=False):
"""
Using a package, it rebuild here for ease of use.
It is 100 % statsmodels OLS.
Y(list[float]) - dependent variable;
X([list[float] | float]) - independent variable;
multiple_X [int, default=1] if there are mutiple factors (Xes), set the number of factor columns
"""
Y = np.array(Y).reshape(-1, 1)
X = np.array(X).reshape(-1, multiple_X)
if integrate:
integrations, Y, X = data_tests.stationarity.forceSTATxy(Y, X)
if alfa:
X = add_constant(X)
model = OLS(Y, X, missing='drop' if fix_nan else 'none').fit()
return model if not integrate else (model, integrations)
def compute_variance_inflation_factor(X: np.array) -> np.array:
"""
Compute the variance inflation factor for each features of a matrix
Parameters
----------
{X}
Returns
-------
vif: np.array of shape = (n_features)
variance inflation factor of each features of the input matrix
"""
# Add a constant columns as suggest here:
# https://stackoverflow.com/questions/42658379/variance-inflation-factor-in-python
X = add_constant(X, prepend=True)
vif = np.array([oi.variance_inflation_factor(X, j) for j in range(X.shape[1])])
# remove the firs element corresponding to the constant col
vif = np.delete(vif, 0)
vif[np.isnan(vif)] = np.inf
return vif
def fit(self, X, y, force_include_idx=None):
''' Estimate a model using Post-Lasso
X: X matrix (without intercept)
y: y vector
force_include_idx: column indexes that ALWAYS is
included in the OLS model, regardless of their
status in the lasso stage.
'''
self.lasso_model = self.lasso_model.fit(X, y)
self.coefs = np.insert(
self.lasso_model.coef_, 0,
self.lasso_model.intercept_) # inserts intercepts in the first col
self.subset_cols = np.where(self.coefs != 0)[
0] # select variables for which the coef after lasso is not zero
if force_include_idx is not None: # add cols defined in force_include_idx to subset_cols
self.subset_cols = np.union1d(self.subset_cols, force_include_idx)
self.relevant_x = add_constant(
X
)[:, self.
subset_cols] # add constant to X and choose only the subset cols
self.ols_model = OLS(y, self.relevant_x).fit()
return self
def variance_inflation_factors(exog_df):
'''
Parameters
----------
exog_df : dataframe, (nobs, k_vars)
design matrix with all explanatory variables, as for example used in
regression.
Returns
-------
vif : Series
variance inflation factors
'''
exog_df = add_constant(exog_df)
vifs = pd.Series([
1 / (1. -
OLS(exog_df[col].values,
exog_df.loc[:, exog_df.columns != col].values).fit().rsquared)
for col in exog_df
],
index=exog_df.columns,
name='VIF')
return vifs
def gen_data(nobs, nvar, const, pandas=False, missing=0.0, weights=False):
rs = np.random.RandomState(987499302)
x = rs.standard_normal((nobs, nvar))
cols = ["x{0}".format(i) for i in range(nvar)]
if const:
x = tools.add_constant(x)
cols = ["const"] + cols
if missing > 0.0:
mask = rs.random_sample(x.shape) < missing
x[mask] = np.nan
if x.shape[1] > 1:
y = x[:, :-1].sum(1) + rs.standard_normal(nobs)
else:
y = x.sum(1) + rs.standard_normal(nobs)
w = rs.chisquare(5, y.shape[0]) / 5
if pandas:
idx = pd.date_range("12-31-1999", periods=nobs)
x = pd.DataFrame(x, index=idx, columns=cols)
y = pd.Series(y, index=idx, name="y")
w = pd.Series(w, index=idx, name="weights")
if not weights:
w = None
return y, x, w
def calculate_QQplot(data1, data2, a=0):
def _sample_quantiles(data):
probplot = gofplots.ProbPlot(np.array(data, dtype=float), a=a)
return probplot.sample_quantiles
def _match_quantile_probabilities(quantiles1, quantiles2):
if len(quantiles1) > len(quantiles2):
quantiles2, quantiles1 = _match_quantile_probabilities(
quantiles2, quantiles1)
else:
N_obs = len(quantiles1)
probs = gofplots.plotting_pos(N_obs, a)
quantiles2 = scstats.mstats.mquantiles(quantiles2, probs)
return quantiles1, quantiles2
s1, s2 = _sample_quantiles(data1), _sample_quantiles(data2)
s1, s2 = _match_quantile_probabilities(s1, s2)
linreg_result = OLS(s2, add_constant(s1)).fit()
s2_fitted = linreg_result.fittedvalues
r = np.sqrt(linreg_result.rsquared)
return s1, s2, s2_fitted, r
def glm_regularized_AIC(X,
Y,
reg_mod,
unreg_mod,
tol=1e-6,
method="kawano",
family="binomial"):
"""
Calculate AIC for a Generalized Linear Model with regularization.
See 'AIC for the Lasso in GLMs', Y. Ninomiya and S. Kawano (2016)
Parameters
----------
X : numpy array or pandas dataframe
Feature or design matrix.
Y : numpy array or pandas series
Target or response variable.
reg_mod : sklearn, or similar
The regularized model.
unreg_mod : sklearn, or similar
The unregularized model.
tol : float, optional
Tolerance cutoff for counting non-zero coefficients. The default is
1e-6.
method : str, optional
The method for calculating the AIC. Either `kawano` or `Hastie`.
The default is "kawano".
family : str, optional
The type of generalised linear model. The default is "binomial".
Raises
------
ValueError
Raised if an invalid family is picked.
Returns
-------
aic : float
The calculated AIC.
"""
# requires predict_proba method for logreg, and predict method for others, for poisson, predict output should be lambda, i.e. it should already be exponentiated
if isinstance(X, pd.DataFrame):
X = X.values
if isinstance(Y, pd.DataFrame or pd.Series):
Y = Y.values
aic = None
if family == "binomial":
nllf = glm_likelihood_bernoulli
unreg_prob = unreg_mod.predict_proba(X)[:, 1]
reg_prob = reg_mod.predict_proba(X)[:, 1]
y_mat_unreg = np.diag(unreg_prob * (1 - unreg_prob))
y_mat_reg = np.diag(reg_prob * (1 - reg_prob))
elif family == "poisson":
nllf = glm_likelihood_poisson
unreg_pred = unreg_mod.predict(X)
reg_pred = reg_mod.predict(X)
y_mat_unreg = np.diag(unreg_prob)
y_mat_reg = np.diag(reg_prob)
elif family == "gaussian":
nllf = glm_likelihood_gaussian
unreg_pred = unreg_mod.predict(X)
reg_pred = reg_mod.predict(X)
y_mat_unreg = np.diag(unreg_pred)
y_mat_reg = np.diag(reg_pred)
else:
raise ValueError("Not a valid family")
reg_mod_coef = np.concatenate(
(reg_mod.intercept_, np.squeeze(reg_mod.coef_)))
nonzero_idx = np.where(
[True if np.abs(coef) > tol else False for coef in reg_mod_coef])[0]
if method == "kawano":
X_nz = add_constant(X[:, nonzero_idx], prepend=True)
j22 = np.linalg.multi_dot([X_nz.T, y_mat_reg, X_nz])
j22_2 = np.linalg.multi_dot([X_nz.T, y_mat_unreg, X_nz])
negloglike = nllf(reg_mod_coef, X, Y, lamb=0, l_norm=0)
aic = 2 * negloglike + np.sum(np.diag(np.linalg.inv(j22).dot(j22_2)))
else:
# Tibshirani, Hastie, Zou 2007, On the degrees of freedom on the lasso
negloglike = nllf(reg_mod_coef, X, Y, lamb=0, l_norm=0)
# Not 100% sure on this calculation. should it be 2*len(nonzero_idx),
#the count of nonzero columns, or 2*mean(non_zero_idx)?
aic = 2 * negloglike + 2 * len(nonzero_idx)
return aic
if len(df) == 0:
model = irimodel
else:
pred = irimodel.predict(df['station.longitude'].values,
df['station.latitude'].values)
error = pred - df[metric].values
print(df[metric].values)
print(pred)
print(error)
print(np.sqrt(np.sum(error**2) / np.sum(df.cs.values)),
np.sum(error) / np.sum(df.cs.values))
if metric in ['mufd', 'fof2']:
wls_model = sm.WLS(df[metric].values - pred,
add_constant(pred, prepend=False), df.cs.values)
wls_fit = wls_model.fit_regularized(alpha=np.array([1, 3]), L1_wt=0)
coeff = wls_fit.params
coeff[0] = coeff[0] + 1
print(coeff)
irimodel = LinearModel(irimodel, coeff[0], coeff[1])
pred = irimodel.predict(df['station.longitude'].values,
df['station.latitude'].values)
error = pred - df[metric].values
print(df[metric].values)
print(pred)
print(error)
print(np.sqrt(np.sum(error**2) / np.sum(df.cs.values)),
np.sum(error) / np.sum(df.cs.values))
def test_glm(constraints=None):
# More comprehensive tests against GLM estimates (this is sort of redundant
# given `test_ols`, but this is mostly to complement the tests in
# `test_glm_constrained`)
endog = dta.infl
exog = add_constant(dta[['unemp', 'm1']])
mod = RecursiveLS(endog, exog, constraints=constraints)
res = mod.fit()
mod_glm = GLM(endog, exog)
if constraints is None:
res_glm = mod_glm.fit()
else:
res_glm = mod_glm.fit_constrained(constraints=constraints)
# Regression coefficients, standard errors, and estimated scale
assert_allclose(res.params, res_glm.params)
assert_allclose(res.bse, res_glm.bse, atol=1e-6)
# Note: scale here is computed according to Harvey, 1989, 4.2.5, and is
# the called the ML estimator and sometimes (e.g. later in section 5)
# denoted \tilde \sigma_*^2
assert_allclose(res.filter_results.obs_cov[0, 0], res_glm.scale)
# DoF
# Note: GLM does not include intercept in DoF, so modify by -1
assert_equal(res.df_model - 1, res_glm.df_model)
# OLS residuals are equivalent to smoothed forecast errors
# (the latter are defined as e_t|T by Harvey, 1989, 5.4.5)
# (this follows since the smoothed state simply contains the
# full-information estimates of the regression coefficients)
actual = (mod.endog[:, 0] -
np.sum(mod['design', 0, :, :] * res.smoothed_state, axis=0))
assert_allclose(actual, res_glm.resid_response, atol=1e-7)
# Given the estimate of scale as `sum(v_t^2 / f_t) / (T - d)` (see
# Harvey, 1989, 4.2.5 on p. 183), then llf_recursive is equivalent to the
# full OLS loglikelihood (i.e. without the scale concentrated out).
desired = mod_glm.loglike(res_glm.params, scale=res_glm.scale)
assert_allclose(res.llf_recursive, desired)
# Alternatively, we can construct the concentrated OLS loglikelihood
# by computing the scale term with `nobs` in the denominator rather than
# `nobs - d`.
scale_alternative = np.sum(
(res.standardized_forecasts_error[0, 1:] *
res.filter_results.obs_cov[0, 0]**0.5)**2) / mod.nobs
llf_alternative = np.log(
norm.pdf(res.resid_recursive, loc=0,
scale=scale_alternative**0.5)).sum()
assert_allclose(llf_alternative, res_glm.llf)
# Prediction
# TODO: prediction in this case is not working.
if constraints is None:
design = np.ones((1, 3, 10))
actual = res.forecast(10, design=design)
assert_allclose(actual, res_glm.predict(np.ones((10, 3))))
else:
design = np.ones((2, 3, 10))
assert_raises(NotImplementedError, res.forecast, 10, design=design)
# Hypothesis tests
actual = res.t_test('m1 = 0')
desired = res_glm.t_test('m1 = 0')
assert_allclose(actual.statistic, desired.statistic)
assert_allclose(actual.pvalue, desired.pvalue, atol=1e-15)
actual = res.f_test('m1 = 0')
desired = res_glm.f_test('m1 = 0')
assert_allclose(actual.statistic, desired.statistic)
assert_allclose(actual.pvalue, desired.pvalue)
# Information criteria
# Note: the llf and llf_obs given in the results are based on the Kalman
# filter and so the ic given in results will not be identical to the
# OLS versions. Additionally, llf_recursive is comparable to the
# non-concentrated llf, and not the concentrated llf that is by default
# used in OLS. Compute new ic based on llf_alternative to compare.
actual_aic = aic(llf_alternative, res.nobs_effective, res.df_model)
assert_allclose(actual_aic, res_glm.aic)
except ImportError:
have_matplotlib = False
current_path = os.path.dirname(os.path.abspath(__file__))
results_R_path = 'results' + os.sep + 'results_rls_R.csv'
results_R = pd.read_csv(current_path + os.sep + results_R_path)
results_stata_path = 'results' + os.sep + 'results_rls_stata.csv'
results_stata = pd.read_csv(current_path + os.sep + results_stata_path)
dta = macrodata.load_pandas().data
dta.index = pd.date_range(start='1959-01-01', end='2009-07-01', freq='QS')
endog = dta['cpi']
exog = add_constant(dta['m1'])
def test_endog():
# Tests for numpy input
mod = RecursiveLS(endog.values, exog.values)
res = mod.fit()
# Test the RLS estimates against OLS estimates
mod_ols = OLS(endog, exog)
res_ols = mod_ols.fit()
assert_allclose(res.params, res_ols.params)
# Tests for 1-dim exog
mod = RecursiveLS(endog, dta['m1'].values)
res = mod.fit()
ax.set_xlabel('YEAR')
ax.set_ylabel('DEC')
plt.show()
from sklearn import linear_model, feature_selection, preprocessing
from sklearn.model_selection import train_test_split
import statsmodels.formula.api as sm
from statsmodels.tools.eval_measures import mse
from statsmodels.tools import add_constant
from sklearn.metrics import mean_squared_error
X = df.values.copy()
X_train, X_valid, y_train, y_valid = train_test_split(X[:, :-1],
X[:, -1],
train_size=0.80)
result = sm.OLS(y_train, add_constant(X_train)).fit()
result.summary()
result = sm.OLS(y_train, add_constant(X_train)).fit()
result.summary()
ypred = result.predict(add_constant(X_valid))
print(mse(ypred, y_valid))
fig, ax = plt.subplots(1, 1)
ax.scatter(y_valid, ypred)
ax.set_xlabel('Actual')
ax.set_ylabel('Prediction')
plt.show()
# In[ ]:
# In[ ]:
square = lambda row: row**2
sum_of_squares = df['difference'].apply(square).sum()
return(sum_of_squares)
x0 = [-20, .0008, 1.1]
estimator(x0)
optimize.minimize(estimator, x0, method='nelder-mead', options={'xtol': 1e-8, 'disp': True})
clf = linear_model.LinearRegression()
x = df[['AADT', 'L']].as_matrix()
y = df['Crashes']
clf.fit(x, y)
clf.coef_
clf.intercept_
model = OLS(y, add_constant(x))
model_fit = model.fit()
model_fit.summary()
def estimator(x, row_in='Crashes'):
estimated = lambda row: exp(x[0] + x[1] * row['AADT'] + x[2] * row['L'])
df['estimated'] = df.apply(estimated, axis=1)
#probability = lambda row: (row['estimated']**row[row_in] * exp(-row['estimated'])) / factorial(row[row_in])
probability = lambda row: poisson.pmf(row[row_in], row['estimated'])
df['probability'] = df.apply(probability, axis=1)
product = df['probability'].product()
return(-product)
x0 = [1.6, .0000026, .032]
estimator(x0)
optimize.minimize(estimator, x0, method='nelder-mead', options={'xtol': 1e-8, 'disp': True})
plt.show() # 1.4 df.hist() plt.show() # Part 2 # 2.1 from statsmodels.discrete.discrete_model import Logit from statsmodels.tools import add_constant X = df[['gre', 'gpa', 'rank']].values X_const = add_constant(X, prepend=True) y = df['admit'].values logit_model = Logit(y, X_const).fit() # 2.2 logit_model.summary() # 2.3 import numpy as np from sklearn.cross_validation import KFold from sklearn.linear_model import LogisticRegression from sklearn.metrics import accuracy_score, precision_score, recall_score
from statsmodels.tools import add_constant
from numpy.testing import assert_equal, assert_raises, assert_allclose
current_path = os.path.dirname(os.path.abspath(__file__))
results_R_path = 'results' + os.sep + 'results_rls_R.csv'
results_R = pd.read_csv(current_path + os.sep + results_R_path)
results_stata_path = 'results' + os.sep + 'results_rls_stata.csv'
results_stata = pd.read_csv(current_path + os.sep + results_stata_path)
dta = macrodata.load_pandas().data
dta.index = pd.date_range(start='1959-01-01', end='2009-07-01', freq='QS')
endog = dta['cpi']
exog = add_constant(dta['m1'])
def test_endog():
# Tests for numpy input
mod = RecursiveLS(endog.values, exog.values)
res = mod.fit()
# Test the RLS estimates against OLS estimates
mod_ols = OLS(endog, exog)
res_ols = mod_ols.fit()
assert_allclose(res.params, res_ols.params)
# Tests for 1-dim exog
mod = RecursiveLS(endog, dta['m1'].values)
res = mod.fit()
def __init__(self):
data = stackloss.load()
data.exog = add_constant(data.exog)
self.res1 = OLS(data.endog, data.exog).fit()
self.res2 = RegressionResults()
sn.countplot(x='TenYearCHD', data=heart_df)
# There are 3179 patents with no heart disease and 572 patients with risk of heart disease.
# In[21]:
sn.pairplot(data=heart_df)
# In[22]:
heart_df.describe()
# In[23]:
from statsmodels.tools import add_constant as add_constant
heart_df_constant = add_constant(heart_df)
heart_df_constant.head()
# In[24]:
st.chisqprob = lambda chisq, df: st.chi2.sf(chisq, df)
cols = heart_df_constant.columns[:-1]
model = sm.Logit(heart_df.TenYearCHD, heart_df_constant[cols])
result = model.fit()
result.summary()
# In[43]:
def back_feature_elem(data_frame, dep_var, col_list):
""" Takes in the dataframe, the dependent variable and a list of column names, runs the regression repeatedly eleminating feature with the highest
# label encoding and one hot encoding categorical variables: Pclass, Sex, Embarked
dataframe = pd.get_dummies(dataframe,
columns=['Pclass', 'Sex'],
drop_first=True)
# for now feature scaling seems unnecessary, but we'll add it later if it turns out to be required
# extract independent and dependent variable matrices
X = dataframe.drop(labels=['PassengerId', 'Survived'], axis=1)
y = dataframe._getitem_column('Survived')
## Backward Elimination
# add a column of 1s to represent x0 variable (intercept)
X = smtools.add_constant(X)
# use Backward Elimination to get rid of insignificant variables
significance_level = 0.05
X = toolkit.backward_elimination_using_pvalues(X, y, significance_level)
# X = toolkit.backward_elimination_using_adjR2(X, y)
# Fitting Decision Tree Classification to the Training set
accuracies = {}
std = {}
classifier = DecisionTreeClassifier()
accuracies['Decision Tree'], std['Decision Tree'] = classifier.classify(X, y)
# Fitting Random Forest Classification to the Training set
classifier = RandomForestClassifier()
accuracies['Random Forest'], std['Random Forest'] = classifier.classify(X, y)
y = np.array([data['sales']]).reshape(-1, 1)
# %%
from sklearn.linear_model import LinearRegression
model = LinearRegression()
model.fit(X, y)
score = model.score(X, y)
print(f"R2 Score: {score}")
print('Weight coefficients: ', model.coef_)
# %%
# << Statsmodels >>
# X need to add constant to match the results from scikit learn
X1 = stat.add_constant(X)
model = sm.OLS(y, X1)
results = model.fit()
print(results.summary())
# %%
# Regression Model with Qualitative Predictors ---------------
# load data
path = '/Users/michaelshih/Documents/code/education/statistical_learining/'
subfolder = 'resource'
filename = 'Credit.csv'
filedir = os.path.join(path, subfolder, filename)
print(filedir)
data = pd.read_csv(filedir, index_col=0)
def test_design(self):
npt.assert_equal(self.model.exog,
add_constant(self.data.exog, prepend=True))
def test_design(self):
npt.assert_equal(self.model.exog,
add_constant(self.data.exog, prepend=True))
def test_glm(constraints=None):
# More comprehensive tests against GLM estimates (this is sort of redundant
# given `test_ols`, but this is mostly to complement the tests in
# `test_glm_constrained`)
endog = dta.infl
exog = add_constant(dta[['unemp', 'm1']])
mod = RecursiveLS(endog, exog, constraints=constraints)
res = mod.fit()
mod_glm = GLM(endog, exog)
if constraints is None:
res_glm = mod_glm.fit()
else:
res_glm = mod_glm.fit_constrained(constraints=constraints)
# Regression coefficients, standard errors, and estimated scale
assert_allclose(res.params, res_glm.params)
assert_allclose(res.bse, res_glm.bse, atol=1e-6)
# Note: scale here is computed according to Harvey, 1989, 4.2.5, and is
# the called the ML estimator and sometimes (e.g. later in section 5)
# denoted \tilde \sigma_*^2
assert_allclose(res.filter_results.obs_cov[0, 0], res_glm.scale)
# DoF
# Note: GLM does not include intercept in DoF, so modify by -1
assert_equal(res.df_model - 1, res_glm.df_model)
# OLS residuals are equivalent to smoothed forecast errors
# (the latter are defined as e_t|T by Harvey, 1989, 5.4.5)
# (this follows since the smoothed state simply contains the
# full-information estimates of the regression coefficients)
actual = (mod.endog[:, 0] -
np.sum(mod['design', 0, :, :] * res.smoothed_state, axis=0))
assert_allclose(actual, res_glm.resid_response, atol=1e-7)
# Given the estimate of scale as `sum(v_t^2 / f_t) / (T - d)` (see
# Harvey, 1989, 4.2.5 on p. 183), then llf_recursive is equivalent to the
# full OLS loglikelihood (i.e. without the scale concentrated out).
desired = mod_glm.loglike(res_glm.params, scale=res_glm.scale)
assert_allclose(res.llf_recursive, desired)
# Alternatively, we can construct the concentrated OLS loglikelihood
# by computing the scale term with `nobs` in the denominator rather than
# `nobs - d`.
scale_alternative = np.sum((
res.standardized_forecasts_error[0, 1:] *
res.filter_results.obs_cov[0, 0]**0.5)**2) / mod.nobs
llf_alternative = np.log(norm.pdf(res.resid_recursive, loc=0,
scale=scale_alternative**0.5)).sum()
assert_allclose(llf_alternative, res_glm.llf)
# Prediction
# TODO: prediction in this case is not working.
if constraints is None:
design = np.ones((1, 3, 10))
actual = res.forecast(10, design=design)
assert_allclose(actual, res_glm.predict(np.ones((10, 3))))
else:
design = np.ones((2, 3, 10))
assert_raises(NotImplementedError, res.forecast, 10, design=design)
# Hypothesis tests
actual = res.t_test('m1 = 0')
desired = res_glm.t_test('m1 = 0')
assert_allclose(actual.statistic, desired.statistic)
assert_allclose(actual.pvalue, desired.pvalue, atol=1e-15)
actual = res.f_test('m1 = 0')
desired = res_glm.f_test('m1 = 0')
assert_allclose(actual.statistic, desired.statistic)
assert_allclose(actual.pvalue, desired.pvalue)
# Information criteria
# Note: the llf and llf_obs given in the results are based on the Kalman
# filter and so the ic given in results will not be identical to the
# OLS versions. Additionally, llf_recursive is comparable to the
# non-concentrated llf, and not the concentrated llf that is by default
# used in OLS. Compute new ic based on llf_alternative to compare.
actual_aic = aic(llf_alternative, res.nobs_effective, res.df_model)
assert_allclose(actual_aic, res_glm.aic)
def _EM_test(self, nuisance_params, params=None, param_nums=None,
b0_vals=None, F=None, survidx=None, uncens_nobs=None,
numcensbelow=None, km=None, uncensored=None, censored=None,
maxiter=None, ftol=None):
"""
Uses EM algorithm to compute the maximum likelihood of a test
Parameters
---------
Nuisance Params: array
Vector of values to be used as nuisance params.
maxiter: int
Number of iterations in the EM algorithm for a parameter vector
Returns
-------
-2 ''*'' log likelihood ratio at hypothesized values and
nuisance params
Notes
-----
Optional parameters are provided by the test_beta function.
"""
iters = 0
params[param_nums] = b0_vals
nuis_param_index = np.int_(np.delete(np.arange(self.model.nvar),
param_nums))
params[nuis_param_index] = nuisance_params
to_test = params.reshape(self.model.nvar, 1)
opt_res = np.inf
diff = np.inf
while iters < maxiter and diff > ftol:
F = F.flatten()
death = np.cumsum(F[::-1])
survivalprob = death[::-1]
surv_point_mat = np.dot(F.reshape(-1, 1),
1. / survivalprob[survidx].reshape(1, - 1))
surv_point_mat = add_constant(surv_point_mat)
summed_wts = np.cumsum(surv_point_mat, axis=1)
wts = summed_wts[np.int_(np.arange(uncens_nobs)),
numcensbelow[uncensored]]
# ^E step
# See Zhou 2005, section 3.
self.model._fit_weights = wts
new_opt_res = self._opt_wtd_nuis_regress(to_test)
# ^ Uncensored weights' contribution to likelihood value.
F = self.new_weights
# ^ M step
diff = np.abs(new_opt_res - opt_res)
opt_res = new_opt_res
iters = iters + 1
death = np.cumsum(F.flatten()[::-1])
survivalprob = death[::-1]
llike = -opt_res + np.sum(np.log(survivalprob[survidx]))
wtd_km = km.flatten() / np.sum(km)
survivalmax = np.cumsum(wtd_km[::-1])[::-1]
llikemax = np.sum(np.log(wtd_km[uncensored])) + \
np.sum(np.log(survivalmax[censored]))
if iters == maxiter:
warnings.warn('The EM reached the maximum number of iterations',
IterationLimitWarning)
return -2 * (llike - llikemax)
def setup_class(cls):
data = stackloss.load(as_pandas=False)
data.exog = add_constant(data.exog)
cls.res1 = OLS(data.endog, data.exog).fit()
cls.res2 = RegressionResults()
def fitPoisson(X, Y):
X = add_constant(X)
return sm.GLM(Y, X, family=sm.families.Poisson()).fit(disp=0)
### accuracy of probabilistic predictions in a set of mutually
### exclusive outcomes i.e. default, non-default
model_vars = [
'term',
'home_ownership',
'grade',
'purpose',
'emp_length',
]
continous_vars = ['funded_amnt', 'dti']
le = preprocessing.LabelEncoder()
y = df_sample['default'].reset_index(drop=True)
X = pd.DataFrame([])
for var in model_vars:
X[var] = le.fit_transform(df_sample[var])
for i in continous_vars:
X[i] = df_sample[i].reset_index(drop=True)
#Add Constant
X = smt.add_constant(X)
# Regression Analysis
logit_model = sm.Logit(y, X)
result = logit_model.fit(disp=0)
y_true = df_sample['default']
y_pred = result.predict()
print(brier_score_loss(y_true, y_pred))
def setup_class(cls):
data = stackloss.load(as_pandas=False)
data.exog = add_constant(data.exog)
cls.res1 = OLS(data.endog, data.exog).fit()
cls.res2 = RegressionResults()
# VIF
# The vif of each column is ok. All of them are smaller than 5, even 2.
def variance_inflation_factor(exog, exog_idx):
k_vars = exog.shape[1]
x_i = exog.iloc[:, exog_idx]
mask = np.arange(k_vars) != exog_idx
x_noti = exog.iloc[:, mask]
r_squared_i = OLS(x_i, x_noti).fit().rsquared
vif = 1. / (1. - r_squared_i)
return vif
# VIF of each column
# we skip the constant column
VIF = [variance_inflation_factor(add_constant(X), i) for i in range(1,X.shape[1]+1)]
regr_1 = OLS(y, add_constant(X)).fit()
# residual distribution
sns.distplot(regr_1.resid) # acting like normal which is good
# since the residual itself is normal, box-cox is not necessary.
# namda = 0.1
# regr_test = OLS((y**namda-1)/namda, add_constant(X)).fit()
# sns.jointplot((y**namda-1)/namda, regr_test.resid)
# sns.distplot(regr_test.resid)
sns.jointplot(y, regr_1.resid) # which looks very strange. maybe the model is not linear at the first place.
#since there is explicit non-linear in this model, we have to add some non-linear covariates in it.
