def get_har_model(dependent, lags):
dist = SkewStudent_Haisun(
random_state=None) #set parameter values for nu and lambda
har = HARX(y=dependent, lags=lags, distribution=dist)
res_train = har.fit() #fit the data
print("-------HAR MODEL" + str(lags) +
" Skewed Student [eta = 10, lam = 0.4] ---------")
har_summ = res_train.summary() #print summary
errors = res_train.resid #call the residual metod
errors = errors.dropna(
) #residuals are nan in bregiining for leng equal to lag
print("Model summary", har_summ)
print("\n")
print("Misspecification of the process tests")
print('\n')
print("Analytics of redisual analysis", get_prelim_stats(errors))
print(get_engle_arch(errors, 22)) #get ARCH-LM
print(get_durbin_watson(errors, 0)) #get DW test statistic
print(get_ljung_box(errors, lags)) #get LjungBox test statistic
return (errors) #getting the model returns the errors from the model.
def get_harx_model(dependent, exogenous, lags, dist):
'''
This function takes a dependent variable(series/dataframe), the exogenous (dataframe), lags (list) and a distribution (arch distribution object)
and fits a model according to the HAR specification.
It sets the covariance estimate as the Bollerslev-Woodbridge Heteroscedastic consistent estimator
It returns the errors of the fitted model
It prints the summary of the model, preliminary statistcs of the residuals, and returns misspecification tests under the stat_testing.py module
'''
har = HARX(y = dependent, x = exogenous, lags = lags, volatility = None, distribution = dist) #HARCH(lags = lags) #, volatility = EGARCH(1,1)
res_train = har.fit(options = {'maxiter': 1000,'ftol':1e-10, 'eps':1e-12}, cov_type='robust', disp = 'off') #fit the data
print("-------HAR MODEL" + str(lags) + str(exogenous) + " ---------")
har_summ = res_train.summary() #print summary
errors = res_train.resid #call the residual metod
errors = errors.dropna() #residuals are nan in bregiining for leng equal to lag
print("Model summary", har_summ)
print("\n")
print("Analytics of redisual analysis", get_prelim_stats(errors))
print("Misspecification of the process tests")
print('\n')
print(get_engle_arch(errors, 22)) #get ARCH-LM
print(get_durbin_watson(errors,0)) #get DW test statistic
print(get_ljung_box(errors, lags)) #get LjungBox test statistic
return (errors) #getting the model returns the errors from the model.
def test_empty_mean(self):
mod = HARX(self.y, None, None, False, volatility=ConstantVariance(),
distribution=Normal())
res = mod.fit()
mod = ZeroMean(self.y, volatility=ConstantVariance(), distribution=Normal())
res_z = mod.fit()
assert res.num_params == res_z.num_params
assert_series_equal(res.params, res_z.params)
assert res.loglikelihood == res_z.loglikelihood
def test_warnings(self):
with warnings.catch_warnings(record=True) as w:
ARX(self.y, lags=[1, 2, 3, 12], hold_back=5)
assert_equal(len(w), 1)
with warnings.catch_warnings(record=True) as w:
HARX(self.y, lags=[[1, 1, 1], [2, 5, 22]], use_rotated=True)
assert_equal(len(w), 1)
har = HARX()
with warnings.catch_warnings(record=True) as w:
har.fit()
assert_equal(len(w), 1)
def test_warnings(self):
with warnings.catch_warnings(record=True) as w:
ARX(self.y, lags=[1, 2, 3, 12], hold_back=5)
assert_equal(len(w), 1)
with warnings.catch_warnings(record=True) as w:
HARX(self.y, lags=[[1, 1, 1], [2, 5, 22]], use_rotated=True)
assert_equal(len(w), 1)
har = HARX()
with warnings.catch_warnings(record=True) as w:
har.fit()
assert_equal(len(w), 1)
def test_harx(self):
harx = HARX(self.y, self.x, lags=[1, 5, 22])
params = np.array([1.0, 0.4, 0.3, 0.2, 1.0, 1.0])
data = harx.simulate(params, self.T, x=randn(self.T + 500, 1))
iv = randn(22, 1)
data = harx.simulate(params,
self.T,
x=randn(self.T + 500, 1),
initial_value=iv)
assert_equal(data.shape, (self.T, 3))
cols = ['data', 'volatility', 'errors']
for c in cols:
assert_true(c in data)
bounds = harx.bounds()
for b in bounds:
assert_equal(b[0], -np.inf)
assert_equal(b[1], np.inf)
assert_equal(len(bounds), 5)
assert_equal(harx.num_params, 1 + 3 + self.x.shape[1])
assert_equal(harx.constant, True)
a, b = harx.constraints()
assert_equal(a, np.empty((0, 5)))
assert_equal(b, np.empty(0))
res = harx.fit()
assert_raises(RuntimeError, res.forecast, horizon=10)
assert_raises(ValueError, res.forecast, params=np.array([1.0, 1.0]))
nobs = self.T - 22
rhs = np.ones((nobs, 5))
y = self.y
lhs = y[22:]
for i in range(self.T - 22):
rhs[i, 1] = y[i + 21]
rhs[i, 2] = np.mean(y[i + 17:i + 22])
rhs[i, 3] = np.mean(y[i:i + 22])
rhs[:, 4] = self.x[22:, 0]
params = np.linalg.pinv(rhs).dot(lhs)
assert_almost_equal(params, res.params[:-1])
assert_equal(harx.first_obs, 22)
assert_equal(harx.last_obs, 1000)
assert_equal(harx.hold_back, None)
assert_equal(harx.lags, [1, 5, 22])
assert_equal(harx.nobs, self.T - 22)
assert_equal(harx.name, 'HAR-X')
assert_equal(harx.use_rotated, False)
harx
harx._repr_html_()
res = harx.fit(cov_type='mle')
res
def test_little_or_no_data(self):
mod = HARX(self.y[:24], lags=[1, 5, 22])
with pytest.raises(ValueError):
mod.fit()
mod = HARX(None, lags=[1, 5, 22])
with pytest.raises(RuntimeError):
mod.fit()
def test_errors(self):
with pytest.raises(ValueError):
ARX(self.y, lags=np.array([[1, 2], [3, 4]]))
x = self.rng.randn(self.y.shape[0] + 1, 1)
with pytest.raises(ValueError):
ARX(self.y, x=x)
with pytest.raises(ValueError):
HARX(self.y, lags=np.eye(3))
with pytest.raises(ValueError):
ARX(self.y, lags=-1)
with pytest.raises(ValueError):
ARX(self.y, x=self.rng.randn(1, 1), lags=-1)
ar = ARX(self.y, lags=1)
with self.assertRaises(ValueError):
d = Normal()
ar.volatility = d
with self.assertRaises(ValueError):
v = GARCH()
ar.distribution = v
x = self.rng.randn(1000, 1)
with pytest.raises(ValueError):
ar.simulate(np.ones(5), 100, x=x)
with pytest.raises(ValueError):
ar.simulate(np.ones(5), 100)
with pytest.raises(ValueError):
ar.simulate(np.ones(3), 100, initial_value=self.rng.randn(10))
with self.assertRaises(ValueError):
ar.volatility = ConstantVariance()
ar.fit(cov_type='unknown')
def test_harx(self):
harx = HARX(self.y, self.x, lags=[1, 5, 22])
params = np.array([1.0, 0.4, 0.3, 0.2, 1.0, 1.0])
data = harx.simulate(params, self.T, x=randn(self.T + 500, 1))
iv = randn(22, 1)
data = harx.simulate(params, self.T, x=randn(self.T + 500, 1),
initial_value=iv)
assert_equal(data.shape, (self.T, 3))
cols = ['data', 'volatility', 'errors']
for c in cols:
assert_true(c in data)
bounds = harx.bounds()
for b in bounds:
assert_equal(b[0], -np.inf)
assert_equal(b[1], np.inf)
assert_equal(len(bounds), 5)
assert_equal(harx.num_params, 1 + 3 + self.x.shape[1])
assert_equal(harx.constant, True)
a, b = harx.constraints()
assert_equal(a, np.empty((0, 5)))
assert_equal(b, np.empty(0))
res = harx.fit()
assert_raises(RuntimeError, res.forecast, horizon=10)
assert_raises(ValueError, res.forecast, params=np.array([1.0, 1.0]))
nobs = self.T - 22
rhs = np.ones((nobs, 5))
y = self.y
lhs = y[22:]
for i in range(self.T - 22):
rhs[i, 1] = y[i + 21]
rhs[i, 2] = np.mean(y[i + 17:i + 22])
rhs[i, 3] = np.mean(y[i:i + 22])
rhs[:, 4] = self.x[22:, 0]
params = np.linalg.pinv(rhs).dot(lhs)
assert_almost_equal(params, res.params[:-1])
assert_equal(harx.first_obs, 22)
assert_equal(harx.last_obs, 1000)
assert_equal(harx.hold_back, None)
assert_equal(harx.lags, [1, 5, 22])
assert_equal(harx.nobs, self.T - 22)
assert_equal(harx.name, 'HAR-X')
assert_equal(harx.use_rotated, False)
harx
harx._repr_html_()
res = harx.fit(cov_type='mle')
res
def test_harx_error(self):
with pytest.raises(ValueError):
HARX(self.y, self.x, lags=[1, -5, 22])
with pytest.raises(ValueError):
HARX(self.y, self.x, lags=[0, 1, 5, 22])
with pytest.raises(ValueError):
HARX(self.y, self.x, lags=[[-1], [3]])
with pytest.raises(ValueError):
HARX(self.y, self.x, lags=[[0], [0]])
with pytest.raises(ValueError):
HARX(self.y, self.x, lags=[[1, 1, 2], [2, 3, 2]])
with pytest.raises(ValueError):
HARX(self.y, self.x, lags=[[[1], [3]]])
def test_har_lag_specifications(self):
""" Test equivalence of alternative lag specifications"""
har = HARX(self.y, lags=[1, 2, 3])
har_r = HARX(self.y, lags=[1, 2, 3], use_rotated=True)
har_r_v2 = HARX(self.y, lags=3, use_rotated=True)
ar = ARX(self.y, lags=[1, 2, 3])
ar_v2 = ARX(self.y, lags=3)
res_har = har.fit(disp=DISPLAY)
res_har_r = har_r.fit(disp=DISPLAY)
res_har_r_v2 = har_r_v2.fit(disp=DISPLAY)
res_ar = ar.fit(disp=DISPLAY)
res_ar_v2 = ar_v2.fit(disp=DISPLAY)
assert_almost_equal(res_har.rsquared, res_har_r.rsquared)
assert_almost_equal(res_har_r_v2.rsquared, res_har_r.rsquared)
assert_almost_equal(np.asarray(res_ar.params),
np.asarray(res_ar_v2.params))
assert_almost_equal(np.asarray(res_ar.params),
np.asarray(res_har_r_v2.params))
assert_almost_equal(np.asarray(res_ar.param_cov),
np.asarray(res_har_r_v2.param_cov))
assert_almost_equal(res_ar.conditional_volatility,
res_har_r_v2.conditional_volatility)
assert_almost_equal(res_ar.resid, res_har_r_v2.resid)
def test_har_lag_specifications(self):
""" Test equivalence of alternative lag specifications"""
har = HARX(self.y, lags=[1, 2, 3])
har_r = HARX(self.y, lags=[1, 2, 3], use_rotated=True)
har_r_v2 = HARX(self.y, lags=3, use_rotated=True)
ar = ARX(self.y, lags=[1, 2, 3])
ar_v2 = ARX(self.y, lags=3)
res_har = har.fit(disp=DISPLAY)
res_har_r = har_r.fit(disp=DISPLAY)
res_har_r_v2 = har_r_v2.fit(disp=DISPLAY)
res_ar = ar.fit(disp=DISPLAY)
res_ar_v2 = ar_v2.fit(disp=DISPLAY)
assert_almost_equal(res_har.rsquared, res_har_r.rsquared)
assert_almost_equal(res_har_r_v2.rsquared, res_har_r.rsquared)
assert_almost_equal(np.asarray(res_ar.params),
np.asarray(res_ar_v2.params))
assert_almost_equal(np.asarray(res_ar.params),
np.asarray(res_har_r_v2.params))
assert_almost_equal(np.asarray(res_ar.param_cov),
np.asarray(res_har_r_v2.param_cov))
assert_almost_equal(res_ar.conditional_volatility,
res_har_r_v2.conditional_volatility)
assert_almost_equal(res_ar.resid, res_har_r_v2.resid)
def test_harx_lag_spec(simulated_data):
harx_1 = HARX(simulated_data, lags=[1, 5, 22])
harx_2 = HARX(simulated_data, lags=[1, 5, 22], use_rotated=True)
harx_3 = HARX(simulated_data, lags=[[1, 1, 1], [1, 5, 22]])
harx_4 = HARX(simulated_data, lags=[[1, 2, 6], [1, 5, 22]])
r2 = harx_1.fit().rsquared
assert_almost_equal(harx_2.fit().rsquared, r2)
assert_almost_equal(harx_3.fit().rsquared, r2)
assert_almost_equal(harx_4.fit().rsquared, r2)
def test_har(self):
har = HARX(self.y, lags=[1, 5, 22])
params = np.array([1.0, 0.4, 0.3, 0.2, 1.0])
data = har.simulate(params, self.T)
assert_equal(data.shape, (self.T, 3))
cols = ['data', 'volatility', 'errors']
for c in cols:
assert c in data
bounds = har.bounds()
for b in bounds:
assert_equal(b[0], -np.inf)
assert_equal(b[1], np.inf)
assert_equal(len(bounds), 4)
assert_equal(har.num_params, 4)
assert_equal(har.constant, True)
a, b = har.constraints()
assert_equal(a, np.empty((0, 4)))
assert_equal(b, np.empty(0))
res = har.fit(disp=DISPLAY)
nobs = self.T - 22
rhs = np.ones((nobs, 4))
y = self.y
lhs = y[22:]
for i in range(self.T - 22):
rhs[i, 1] = y[i + 21]
rhs[i, 2] = np.mean(y[i + 17:i + 22])
rhs[i, 3] = np.mean(y[i:i + 22])
params = np.linalg.pinv(rhs).dot(lhs)
assert_almost_equal(params, res.params[:-1])
with pytest.raises(ValueError):
res.forecast(horizon=6, start=0)
forecasts = res.forecast(horizon=6)
t = self.y.shape[0]
direct = pd.DataFrame(index=np.arange(t),
columns=['h.' + str(i + 1) for i in range(6)],
dtype=np.float64)
params = np.asarray(res.params)
fcast = np.zeros(t + 6)
for i in range(21, t):
fcast[:i + 1] = self.y[:i + 1]
fcast[i + 1:] = 0.0
for h in range(6):
fcast[i + h + 1] = params[0]
fcast[i + h + 1] += params[1] * fcast[i + h:i + h + 1]
fcast[i + h + 1] += params[2] * fcast[
i + h - 4:i + h + 1].mean()
fcast[i + h + 1] += params[3] * fcast[
i + h - 21:i + h + 1].mean()
direct.iloc[i, :] = fcast[i + 1:i + 7]
assert isinstance(forecasts, ARCHModelForecast)
# TODO
# assert_frame_equal(direct, forecasts)
forecasts = res.forecast(res.params, horizon=6)
assert isinstance(forecasts, ARCHModelForecast)
# TODO
# assert_frame_equal(direct, forecasts)
assert_equal(har.hold_back, None)
assert_equal(har.lags, [1, 5, 22])
assert_equal(har.name, 'HAR')
assert_equal(har.use_rotated, False)
har = HARX(self.y_series, lags=[1, 5, 22])
res = har.fit(disp=DISPLAY)
direct = pd.DataFrame(index=self.y_series.index,
columns=['h.' + str(i + 1) for i in range(6)],
dtype=np.float64)
forecasts = res.forecast(horizon=6)
params = np.asarray(res.params)
fcast = np.zeros(t + 6)
for i in range(21, t):
fcast[:i + 1] = self.y[:i + 1]
fcast[i + 1:] = 0.0
for h in range(6):
fcast[i + h + 1] = params[0]
fcast[i + h + 1] += params[1] * fcast[i + h:i + h + 1]
fcast[i + h + 1] += params[2] * fcast[
i + h - 4:i + h + 1].mean()
fcast[i + h + 1] += params[3] * fcast[
i + h - 21:i + h + 1].mean()
direct.iloc[i, :] = fcast[i + 1:i + 7]
assert isinstance(forecasts, ARCHModelForecast)
def test_harx(self):
harx = HARX(self.y, self.x, lags=[1, 5, 22])
assert harx.x is self.x
params = np.array([1.0, 0.4, 0.3, 0.2, 1.0, 1.0])
harx.simulate(params, self.T, x=self.rng.randn(self.T + 500, 1))
iv = self.rng.randn(22, 1)
data = harx.simulate(
params, self.T, x=self.rng.randn(self.T + 500, 1), initial_value=iv
)
assert_equal(data.shape, (self.T, 3))
cols = ["data", "volatility", "errors"]
for c in cols:
assert c in data
bounds = harx.bounds()
for b in bounds:
assert_equal(b[0], -np.inf)
assert_equal(b[1], np.inf)
assert_equal(len(bounds), 5)
assert_equal(harx.num_params, 1 + 3 + self.x.shape[1])
assert_equal(harx.constant, True)
a, b = harx.constraints()
assert_equal(a, np.empty((0, 5)))
assert_equal(b, np.empty(0))
res = harx.fit(disp=DISPLAY)
with pytest.raises(ValueError):
res.forecast(params=np.array([1.0, 1.0]))
nobs = self.T - 22
rhs = np.ones((nobs, 5))
y = self.y
lhs = y[22:]
for i in range(self.T - 22):
rhs[i, 1] = y[i + 21]
rhs[i, 2] = np.mean(y[i + 17 : i + 22])
rhs[i, 3] = np.mean(y[i : i + 22])
rhs[:, 4] = self.x[22:, 0]
params = np.linalg.pinv(rhs).dot(lhs)
assert_almost_equal(params, res.params[:-1])
assert harx.hold_back is None
assert_equal(harx.lags, [1, 5, 22])
assert_equal(harx.name, "HAR-X")
assert_equal(harx.use_rotated, False)
assert isinstance(harx.__repr__(), str)
harx._repr_html_()
res = harx.fit(cov_type="mle", disp=DISPLAY)
assert isinstance(res.__repr__(), str)
def get_forecast_5d(dependent, exogenous, lags, volatility, distribution_):
har = HARX(y = dependent, x = exogenous, lags = [1,5,22], volatility = volatility, distribution = distribution_)
res = har.fit(options = {'maxiter': 10000, 'ftol':1e-12, 'eps':1e-14}, cov_type='robust', last_obs = split_date)
forecast = res.forecast(horizon = 5, align = 'target', method = 'bootstrap', start = split_date)
forecast = forecast.mean.dropna()
return forecast
def get_forecast_egarch(dependent, exogenous, lags, distribution_):
har = HARX(y = dependent, x = exogenous, lags = [1,5,22], volatility = EGARCH(1,1), distribution = distribution_)
res = har.fit(options = {'maxiter': 10000}, cov_type='robust', first_obs=start_date, last_obs = split_date)
forecast = res.forecast(horizon = 1, align = 'target',start = split_date)
forecast = forecast.mean.dropna()
return forecast
def test_har(self):
har = HARX(self.y, lags=[1, 5, 22])
params = np.array([1.0, 0.4, 0.3, 0.2, 1.0])
data = har.simulate(params, self.T)
assert_equal(data.shape, (self.T, 3))
cols = ['data', 'volatility', 'errors']
for c in cols:
assert c in data
bounds = har.bounds()
for b in bounds:
assert_equal(b[0], -np.inf)
assert_equal(b[1], np.inf)
assert_equal(len(bounds), 4)
assert_equal(har.num_params, 4)
assert_equal(har.constant, True)
a, b = har.constraints()
assert_equal(a, np.empty((0, 4)))
assert_equal(b, np.empty(0))
res = har.fit(disp=DISPLAY)
nobs = self.T - 22
rhs = np.ones((nobs, 4))
y = self.y
lhs = y[22:]
for i in range(self.T - 22):
rhs[i, 1] = y[i + 21]
rhs[i, 2] = np.mean(y[i + 17:i + 22])
rhs[i, 3] = np.mean(y[i:i + 22])
params = np.linalg.pinv(rhs).dot(lhs)
assert_almost_equal(params, res.params[:-1])
with pytest.raises(ValueError):
res.forecast(horizon=6, start=0)
forecasts = res.forecast(horizon=6)
t = self.y.shape[0]
direct = pd.DataFrame(index=np.arange(t),
columns=['h.' + str(i + 1) for i in range(6)],
dtype=np.float64)
params = np.asarray(res.params)
fcast = np.zeros(t + 6)
for i in range(21, t):
fcast[:i + 1] = self.y[:i + 1]
fcast[i + 1:] = 0.0
for h in range(6):
fcast[i + h + 1] = params[0]
fcast[i + h + 1] += params[1] * fcast[i + h:i + h + 1]
fcast[i + h + 1] += params[2] * fcast[
i + h - 4:i + h + 1].mean()
fcast[i + h + 1] += params[3] * fcast[
i + h - 21:i + h + 1].mean()
direct.iloc[i, :] = fcast[i + 1:i + 7]
assert isinstance(forecasts, ARCHModelForecast)
# TODO
# assert_frame_equal(direct, forecasts)
forecasts = res.forecast(res.params, horizon=6)
assert isinstance(forecasts, ARCHModelForecast)
# TODO
# assert_frame_equal(direct, forecasts)
assert_equal(har.hold_back, None)
assert_equal(har.lags, [1, 5, 22])
assert_equal(har.name, 'HAR')
assert_equal(har.use_rotated, False)
har = HARX(self.y_series, lags=[1, 5, 22])
res = har.fit(disp=DISPLAY)
direct = pd.DataFrame(index=self.y_series.index,
columns=['h.' + str(i + 1) for i in range(6)],
dtype=np.float64)
forecasts = res.forecast(horizon=6)
params = np.asarray(res.params)
fcast = np.zeros(t + 6)
for i in range(21, t):
fcast[:i + 1] = self.y[:i + 1]
fcast[i + 1:] = 0.0
for h in range(6):
fcast[i + h + 1] = params[0]
fcast[i + h + 1] += params[1] * fcast[i + h:i + h + 1]
fcast[i + h + 1] += params[2] * fcast[
i + h - 4:i + h + 1].mean()
fcast[i + h + 1] += params[3] * fcast[
i + h - 21:i + h + 1].mean()
direct.iloc[i, :] = fcast[i + 1:i + 7]
assert isinstance(forecasts, ARCHModelForecast)
