def _fit_start_params_hr(self, order): """ Get starting parameters for fit. Parameters ---------- order : iterable (p,q,k) - AR lags, MA lags, and number of exogenous variables including the constant. Returns ------- start_params : array A first guess at the starting parameters. Notes ----- If necessary, fits an AR process with the laglength selected according to best BIC. Obtain the residuals. Then fit an ARMA(p,q) model via OLS using these residuals for a first approximation. Uses a separate OLS regression to find the coefficients of exogenous variables. References ---------- Hannan, E.J. and Rissanen, J. 1982. "Recursive estimation of mixed autoregressive-moving average order." `Biometrika`. 69.1. """ p,q,k = order start_params = zeros((p+q+k)) endog = self.endog.copy() # copy because overwritten exog = self.exog if k != 0: ols_params = GLS(endog, exog).fit().params start_params[:k] = ols_params endog -= np.dot(exog, ols_params).squeeze() if q != 0: if p != 0: armod = AR(endog).fit(ic='bic', trend='nc') arcoefs_tmp = armod.params p_tmp = armod.k_ar resid = endog[p_tmp:] - np.dot(lagmat(endog, p_tmp, trim='both'), arcoefs_tmp) if p < p_tmp + q: endog_start = p_tmp + q - p resid_start = 0 else: endog_start = 0 resid_start = p - p_tmp - q lag_endog = lagmat(endog, p, 'both')[endog_start:] lag_resid = lagmat(resid, q, 'both')[resid_start:] # stack ar lags and resids X = np.column_stack((lag_endog, lag_resid)) coefs = GLS(endog[max(p_tmp+q,p):], X).fit().params start_params[k:k+p+q] = coefs else: start_params[k+p:k+p+q] = yule_walker(endog, order=q)[0] if q==0 and p != 0: arcoefs = yule_walker(endog, order=p)[0] start_params[k:k+p] = arcoefs return start_params
def pred_density(self, phi, sigma, y=None, h=8, impact_mat=None): """Simulates predictive density...""" if y is None: #xest, yest = self.xest, self.yest xest = lagmat(self.data, maxlag=self._p, trim='backward') xest = add_constant(xest, prepend=False) xest = xest[-self._p] else: xest, yest = lagmat(y, maxlag=self._p, trim="both", original="sep") if self._cons is True: xest = add_constant(xest, prepend=False) x = xest nx = x.shape[0] y = np.zeros((h, self._ny)) if impact_mat == None: impact_mat = np.ones_like(y) impact_mat = np.squeeze(impact_mat) for i in range(0, h): y[i, :] = x.dot( phi) + impact_mat[i] * np.random.multivariate_normal( np.zeros(self._ny), sigma) if self._p > 0: x[:(self._ny * (self._p - 1))] = x[(self._ny):(nx - self._cons)] x[(self._ny * (self._p - 1)):-1] = y[i, :] else: x = y[i, :] return y
def _fit_start_params_hr(self, order): """ Get starting parameters for fit. Parameters ---------- order : iterable (p,q,k) - AR lags, MA lags, and number of exogenous variables including the constant. Returns ------- start_params : array A first guess at the starting parameters. Notes ----- If necessary, fits an AR process with the laglength selected according to best BIC. Obtain the residuals. Then fit an ARMA(p,q) model via OLS using these residuals for a first approximation. Uses a separate OLS regression to find the coefficients of exogenous variables. References ---------- Hannan, E.J. and Rissanen, J. 1982. "Recursive estimation of mixed autoregressive-moving average order." `Biometrika`. 69.1. """ p, q, k = order start_params = zeros((p + q + k)) endog = self.endog.copy() # copy because overwritten exog = self.exog if k != 0: ols_params = GLS(endog, exog).fit().params start_params[:k] = ols_params endog -= np.dot(exog, ols_params).squeeze() if q != 0: if p != 0: armod = AR(endog).fit(ic='bic', trend='nc') arcoefs_tmp = armod.params p_tmp = armod.k_ar resid = endog[p_tmp:] - np.dot( lagmat(endog, p_tmp, trim='both'), arcoefs_tmp) if p < p_tmp + q: endog_start = p_tmp + q - p resid_start = 0 else: endog_start = 0 resid_start = p - p_tmp - q lag_endog = lagmat(endog, p, 'both')[endog_start:] lag_resid = lagmat(resid, q, 'both')[resid_start:] # stack ar lags and resids X = np.column_stack((lag_endog, lag_resid)) coefs = GLS(endog[max(p_tmp + q, p):], X).fit().params start_params[k:k + p + q] = coefs else: start_params[k + p:k + p + q] = yule_walker(endog, order=q)[0] if q == 0 and p != 0: arcoefs = yule_walker(endog, order=p)[0] start_params[k:k + p] = arcoefs return start_params
def _process_inputs(self, X, E=None, lengths=None): if self.n_features == 1: lagged = None if lengths is None: lagged = lagmat(X, maxlag=self.n_lags, trim='forward', original='ex') else: lagged = np.zeros((len(X), self.n_lags)) for i, j in iter_from_X_lengths(X, lengths): lagged[i:j, :] = lagmat(X[i:j], maxlag=self.n_lags, trim='forward', original='ex') return {'obs': X.reshape(-1,1), 'lagged': lagged.reshape(-1, self.n_features, self.n_lags)} else: lagged = None lagged = np.zeros((X.shape[0], self.n_features, self.n_lags)) if lengths is None: tem = lagmat(X, maxlag=self.n_lags, trim='forward', original='ex') for sample in range(X.shape[0]): lagged[sample] = np.reshape\ (tem[sample], (self.n_features, self.n_lags), 'F') else: for i, j in iter_from_X_lengths(X, lengths): lagged[i:j, :] = lagmat(X[i:j], maxlag=self.n_lags, trim='forward', original='ex') lagged.reshape(-1, self.n_featurs, self.n_lags) return {'obs': X, 'lagged': lagged}
def create_dataset(dataset, timestep=1, look_back=1, look_ahead=1): dataX = lagmat(dataset, maxlag=look_back, trim='both', original='ex') dataY = lagmat(dataset[look_back:], maxlag=look_ahead, trim='backward', original='ex') dataX = dataX.reshape(-1, timestep, dataX.shape[1])[:-(look_ahead - 1)] return np.array(dataX), np.array(dataY[:-(look_ahead - 1)])
def maximum_likelihood_estimation(ts, lags): """ Obtain the cointegrating vectors and corresponding eigenvalues """ # Make sure we are working with array, convert if necessary ts = np.asarray(ts) # Calculate the differences of ts ts_diff = np.diff(ts, axis=0) # Calculate lags of ts_diff. ts_diff_lags = lagmat(ts_diff, lags, trim='both') # First lag of ts ts_lag = lagmat(ts, 1, trim='both') # Trim ts_diff and ts_lag ts_diff = ts_diff[lags:] ts_lag = ts_lag[lags:] # Include intercept in the regressions ones = np.ones((ts_diff_lags.shape[0], 1)) ts_diff_lags = np.append(ts_diff_lags, ones, axis=1) # Calculate the residuals of the regressions of diffs and lags # into ts_diff_lags inverse = np.linalg.pinv(ts_diff_lags) u = ts_diff - np.dot(ts_diff_lags, np.dot(inverse, ts_diff)) v = ts_lag - np.dot(ts_diff_lags, np.dot(inverse, ts_lag)) # Covariance matrices of the calculated residuals t = ts_diff_lags.shape[0] Svv = np.dot(v.T, v) / t Suu = np.dot(u.T, u) / t Suv = np.dot(u.T, v) / t Svu = Suv.T # ToDo: check for singular matrices and exit Svv_inv = np.linalg.inv(Svv) Suu_inv = np.linalg.inv(Suu) # Calculate eigenvalues and eigenvectors of the product of covariances cov_prod = np.dot(Svv_inv, np.dot(Svu, np.dot(Suu_inv, Suv))) eigenvalues, eigenvectors = np.linalg.eig(cov_prod) # Use Cholesky decomposition on eigenvectors evec_Svv_evec = np.dot(eigenvectors.T, np.dot(Svv, eigenvectors)) cholesky_factor = np.linalg.cholesky(evec_Svv_evec) eigenvectors = np.dot(eigenvectors, np.linalg.inv(cholesky_factor.T)) # Order the eigenvalues and eigenvectors indices_ordered = np.argsort(eigenvalues) indices_ordered = np.flipud(indices_ordered) # Return the calculated values return eigenvalues[indices_ordered], eigenvectors[:, indices_ordered]
def fit_discrete_state_transition(speed, is_replay, penalty=1E-5, speed_knots=None, diagonal=None): """Estimate the predicted probablity of replay given speed and whether it was a replay in the previous time step. p(I_t | I_t-1, v_t-1) p_I_0, p_I_1 in Long Tao's code Parameters ---------- speed : ndarray, shape (n_time,) is_replay : boolean ndarray, shape (n_time,) speed_knots : ndarray, shape (n_knots,) Returns ------- probability_replay : ndarray, shape (n_time, 2) """ data = pd.DataFrame({ 'is_replay': is_replay.astype(np.float64), 'lagged_is_replay': lagmat(is_replay, maxlag=1).astype(np.float64).squeeze(), 'lagged_speed': lagmat(speed, maxlag=1).squeeze() }).dropna() if speed_knots is None: speed_mid_point = np.nanmedian(speed[speed > 10]) speed_knots = [1., 2., 3., speed_mid_point] MODEL_FORMULA = ( 'is_replay ~ 1 + lagged_is_replay + ' 'cr(lagged_speed, knots=speed_knots, constraints="center")') response, design_matrix = dmatrices(MODEL_FORMULA, data) penalty = np.ones((design_matrix.shape[1], )) * penalty penalty[0] = 0.0 fit = penalized_IRLS(design_matrix, response, family=FAMILY, penalty=penalty) if np.isnan(fit.AIC): logger.error("Discrete state transition failed to fit properly. " "Try specifying `speed_knots`") return partial(predict_probability, design_matrix=design_matrix, coefficients=fit.coefficients)
def _process_inputs(self, X, E=None, lengths=None): # Makes sure inputs have correct shape, generates features lagged = None if lengths is None: lagged = lagmat(X, maxlag=self.n_lags, trim='forward', original='ex') else: lagged = np.zeros((len(X), self.n_lags)) for i, j in iter_from_X_lengths(X, lengths): lagged[i:j, :] = lagmat(X[i:j], maxlag=self.n_lags, trim='forward', original='ex') inputs = {'obs': X.reshape(-1,1), 'lagged': lagged} return inputs
def pacf_ols(x, nlags=40): '''Calculate partial autocorrelations Parameters ---------- x : 1d array observations of time series for which pacf is calculated nlags : int Number of lags for which pacf is returned. Lag 0 is not returned. Returns ------- pacf : 1d array partial autocorrelations, maxlag+1 elements Notes ----- This solves a separate OLS estimation for each desired lag. ''' #TODO: add warnings for Yule-Walker #NOTE: demeaning and not using a constant gave incorrect answers? #JP: demeaning should have a better estimate of the constant #maybe we can compare small sample properties with a MonteCarlo xlags, x0 = lagmat(x, nlags, original='sep') #xlags = sm.add_constant(lagmat(x, nlags), prepend=True) xlags = add_constant(xlags) pacf = [1.] for k in range(1, nlags+1): res = OLS(x0[k:], xlags[k:, :k+1]).fit() #np.take(xlags[k:], range(1,k+1)+[-1], pacf.append(res.params[-1]) return np.array(pacf)
def _estimate_df_regression(y, trend, lags): """Helper function that estimates the core (A)DF regression Parameters ---------- y : ndarray The data for the lag selection trend : {'nc','c','ct','ctt'} The trend order lags : int The number of lags to include in the ADF regression Returns ------- ols_res : OLSResults A results class object produced by OLS.fit() Notes ----- See statsmodels.regression.linear_model.OLS for details on the results returned """ delta_y = diff(y) rhs = lagmat(delta_y[:, None], lags, trim='both', original='in') nobs = rhs.shape[0] lhs = rhs[:, 0].copy() # lag-0 values are lhs, Is copy() necessary? rhs[:, 0] = y[-nobs - 1:-1] # replace lag 0 with level of y rhs = _add_column_names(rhs, lags) if trend != 'nc': rhs = add_trend(rhs.iloc[:, :lags + 1], trend) return OLS(lhs, rhs).fit()
def _estimate_df_regression(y, trend, lags): """Helper function that estimates the core (A)DF regression Parameters ---------- y : array-like, (nobs,) The data for the lag selection trend : str, {'nc','c','ct','ctt'} The trend order lags : int The number of lags to include in the ADF regression Returns ------- ols_res : OLSResults A results class object produced by OLS.fit() Notes ----- See statsmodels.regression.linear_model.OLS for details on the results returned """ delta_y = diff(y) rhs = lagmat(delta_y[:, None], lags, trim='both', original='in') nobs = rhs.shape[0] lhs = rhs[:, 0].copy() # lag-0 values are lhs, Is copy() necessary? rhs[:, 0] = y[-nobs - 1:-1] # replace lag 0 with level of y if trend != 'nc': rhs = add_trend(rhs[:, :lags + 1], trend) return OLS(lhs, rhs).fit()
def load_(infile, nLags=1000): from statsmodels.tsa.tsatools import lagmat assert infile.endswith('.npy') X, Y = np.load(infile) X0 = lagmat(X, nLags, trim='both') ind = len(X)-len(X0) return X0, Y[ind:]
def __init__(self, endog, use_exp=True, h=0.1, p=1, q=1, **kwargs): exog, endog = lagmat(endog, p, trim='both', original='sep', use_pandas=True) super().__init__(endog, add_constant(exog), **kwargs) self.p = p self.q = q self.h = h for plag1 in range(1, p + 1): self.exog_names.append('phi2%d%d' % (plag1, plag1)) # for plag1 in range(1,p+1): # for plag2 in range(plag1,p+1): # self.exog_names.append('phi2%d%d' % (plag1,plag2)) for qlag in range(1, q + 1): self.exog_names.append('gamma%d' % qlag) self.exog_names.append('sigma') # for lag in range(1,max(p,q)+1): # self.exog_names.append('s%d' % lag) self.nlinear_terms = self.p + 1 self.nquad_terms = int(self.p * (self.p + 1) / 2) self.ngamma_terms = self.q self.ninit_terms = max(self.p, self.q)
def _get_mixed_design_mat_part(seas_part, order, seas_order, m): """ Prepares `pP, qQ` parts of the design matrix for SGD. Parameters ---------- seas_part : array_like Either the seasonal part that was previosuly calculated with `_get_seasonal_design_mat_part` for P or for Q. order : int Either p or q of SARIMAX. seas_order : int Either P or Q of SARIMAX. m : int The seasonal period of SARIMAX. Returns ------- A matrix shaped (N, P) or (N, Q) that will correspond to the multiplying terms in SARIMAX's "mixed" parameters i.e. containing both ordinals and seasonals as a result of multiplicative formulation. """ N = seas_part.shape[0] part = np.empty((N, order * seas_order)) for i in range(seas_order): part[:, i * order: (i + 1) * order] = lagmat( seas_part[:, i], maxlag=order ) return part
def GetADFuller(Y, maxlags=None, regression='c'): #Y = np.asarray(Y) Y = Y.T dy = np.diff(Y) if dy.ndim == 1: dy = dy[:, None] ydall = lagmat(dy, maxlags, trim='both', original='in') nobs = ydall.shape[0] ydall[:, 0] = Y[-nobs - 1:-1] dYshort = dy[-nobs:] if regression != 'nc': Z = add_trend(ydall[:, :maxlags + 1], regression) else: Z = ydall[:, :maxlags + 1] resultADFuller = GetOLS(Y=dYshort.T, X=Z.T) K_dash = 2 * (2 * maxlags + 1) AIC = np.log(np.absolute(np.linalg.det( resultADFuller['sigma_hat']))) + 2.0 * K_dash / ( resultADFuller['nobs']) # log(sigma_hat) + 2*K_dash/T BIC = np.log(np.absolute(np.linalg.det(resultADFuller['sigma_hat']))) + ( K_dash / resultADFuller['nobs']) * np.log( resultADFuller['nobs']) # log(sigma_hat) + K_dash/T*log(T) resultADFuller['AIC'] = AIC resultADFuller['BIC'] = BIC resultADFuller['adfstat'] = resultADFuller['tvalues'][0, 0] resultADFuller['maxlag'] = maxlags return resultADFuller
def train(self, data, **kwargs): if self.indexer is not None and isinstance(data, pd.DataFrame): data = self.indexer.get_data(data) lagdata, ndata = lagmat(data, maxlag=self.order, trim="both", original='sep') mqt = QuantReg(ndata, lagdata).fit(0.5) if self.alpha is not None: uqt = QuantReg(ndata, lagdata).fit(1 - self.alpha) lqt = QuantReg(ndata, lagdata).fit(self.alpha) self.mean_qt = [k for k in mqt.params] if self.alpha is not None: self.upper_qt = [k for k in uqt.params] self.lower_qt = [k for k in lqt.params] if self.dist: self.dist_qt = [] for alpha in np.arange(0.05,0.5,0.05): lqt = QuantReg(ndata, lagdata).fit(alpha) uqt = QuantReg(ndata, lagdata).fit(1 - alpha) lo_qt = [k for k in lqt.params] up_qt = [k for k in uqt.params] self.dist_qt.append([lo_qt, up_qt]) self.shortname = "QAR(" + str(self.order) + ") - " + str(self.alpha)
def lag_func(data,lag,col): lag = lag X = lagmat(data["diff"], lag) lagged = data.copy() for c in range(1,lag+1): lagged[col+"%d" % c] = X[:, c-1] return lagged
def fit_speed_likelihood(speed, is_replay, speed_threshold=4.0): """Fits the standard deviation of the change in speed for the replay and non-replay state. Parameters ---------- speed : ndarray, shape (n_time,) is_replay : ndarray, shape (n_time,) speed_threshold : float, optional Returns ------- speed_likelihood : function """ is_replay = np.asarray(is_replay).astype(bool) lagged_speed = lagmat(speed, 1) lagged_speed[0] = speed[0] replay_coefficients, replay_scale = fit_speed_model( speed[is_replay], lagged_speed[is_replay]) no_replay_coefficients, no_replay_scale = fit_speed_model( speed[~is_replay], lagged_speed[~is_replay]) return partial(speed_likelihood, replay_coefficients=replay_coefficients, replay_scale=replay_scale, no_replay_coefficients=no_replay_coefficients, no_replay_scale=no_replay_scale, speed_threshold=speed_threshold)
def selectlag_IC(data, maxlag, penalty): # Select VAR lag length using information criterion # preliminaries n_x = np.size(data, 1) # compute information criterion for each possible lag length IC = np.empty((maxlag + 1, 1)) for i in range(1, maxlag + 1): # set lag length p = i # estimate VAR data_est = data[maxlag - p:, :] T = np.size(data_est, 0) T_VAR = T - p X = lagmat(data_est, p, original='ex') X = X[p:, :] Y = data_est[p:, :] X = np.column_stack((X, np.ones((len(X), 1)))) VAR_coeff = (np.linalg.inv(X.T @ X)) @ (X.T @ Y) VAR_res = Y - X @ VAR_coeff # Sigma_u = (VAR_res'*VAR_res)/(T_VAR-n_x*p-1) Sigma_u = (VAR_res.T @ VAR_res) / T_VAR # compute information criterion T = np.size(data, 0) - maxlag # IC(i) = log(det(Sigma_u)) + i * n_x^2 * 2/T IC[i] = np.log(np.linalg.det(Sigma_u)) + i * n_x**2 * penalty(T) lag = np.where(IC == min(IC)) return int(lag[0][0])
def _init_model(self) -> None: """Should be called whenever the model is initialized or changed""" self._reformat_lags() self._check_specification() nobs_orig = self._y.shape[0] if self.constant: reg_constant = np.ones((nobs_orig, 1), dtype=np.float64) else: reg_constant = np.ones((nobs_orig, 0), dtype=np.float64) if self.lags is not None and nobs_orig > 0: maxlag = np.max(self.lags) lag_array = lagmat(self._y, maxlag) reg_lags = np.empty((nobs_orig, self._lags.shape[1]), dtype=np.float64) for i, lags in enumerate(self._lags.T): reg_lags[:, i] = np.mean(lag_array[:, lags[0]:lags[1]], 1) else: reg_lags = np.empty((nobs_orig, 0), dtype=np.float64) if self._x is not None: reg_x = self._x else: reg_x = np.empty((nobs_orig, 0), dtype=np.float64) self.regressors = np.hstack((reg_constant, reg_lags, reg_x))
def adf(ts, maxlag=1): """ Augmented Dickey-Fuller unit root test """ # make sure we are working with an array, convert if necessary ts = np.asarray(ts) # Get the dimension of the array nobs = ts.shape[0] # Calculate the discrete difference tsdiff = np.diff(ts) # Create a 2d array of lags, trim invalid observations on both sides tsdall = lagmat(tsdiff[:, None], maxlag, trim='both', original='in') # Get dimension of the array nobs = tsdall.shape[0] # replace 0 xdiff with level of x tsdall[:, 0] = ts[-nobs - 1:-1] tsdshort = tsdiff[-nobs:] # Calculate the linear regression using an ordinary least squares model results = OLS(tsdshort, add_trend(tsdall[:, :maxlag + 1], 'c')).fit() adfstat = results.tvalues[0] # Get approx p-value from a precomputed table (from stattools) pvalue = mackinnonp(adfstat, 'c', N=1) return pvalue
def __init__(self, endog): if not isinstance(endog, pd.DataFrame): endog = pd.DataFrame(endog) k = endog.shape[1] augmented = lagmat(endog, 1, trim='both', original='in', use_pandas=True) endog = augmented.iloc[:, :k] exog = add_constant(augmented.iloc[:, k:]) k_states = k * (k + 1) super().__init__(endog, k_states=k_states) self.ssm.initialize('known', stationary_cov=np.eye(self.k_states) * 5) self['design'] = np.zeros((self.k_endog, self.k_states, self.nobs)) for i in range(self.k_endog): start = i * (self.k_endog + 1) end = start + self.k_endog + 1 self['design', i, start:end, :] = exog.T self['transition'] = np.eye(k_states) self['selection'] = np.eye(k_states) self._obs_cov_slice = np.s_[:self.k_endog * (self.k_endog + 1) // 2] self._obs_cov_tril = np.tril_indices(self.k_endog) self._state_cov_slice = np.s_[-self.k_states:] self._state_cov_ix = ('state_cov',) + np.diag_indices(self.k_states)
def sample(self, nsim=1000, y=None, flatten_output=False): if y is None: y = self.data ydum, xdum = self._prior.get_pseudo_obs() xest, yest = lagmat(y, maxlag=self._p, trim="both", original="sep") if self._cons is True: xest = add_constant(xest, prepend=False) #if not (ydum == None).all(): yest = np.vstack((ydum, yest)) xest = np.vstack((xdum, xest)) # This is just a random initialization point.... phihatT = np.linalg.solve(xest.T.dot(xest), xest.T.dot(yest)) S = (yest - xest.dot(phihatT)).T.dot(yest - xest.dot(phihatT)) nu = yest.shape[0] - self._p * self._ny - self._cons * 1 omega = xest.T.dot(xest) muphi = phihatT phis, sigmas = NormInvWishart(phihatT, omega, S, nu).rvs(nsim) if flatten_output: return np.array([ np.r_[phis[i].flatten(order='F'), vech(sigmas[i])] for i in range(nsim) ]) else: return phis, sigmas return phis, sigmas
def _init_model(self): """Should be called whenever the model is initialized or changed""" self._reformat_lags() self._check_specification() nobs_orig = self._y.shape[0] if self.constant: reg_constant = ones((nobs_orig, 1), dtype=np.float64) else: reg_constant = ones((nobs_orig, 0), dtype=np.float64) if self.lags is not None and nobs_orig > 0: maxlag = np.max(self.lags) lag_array = lagmat(self._y, maxlag) reg_lags = empty((nobs_orig, self._lags.shape[1]), dtype=np.float64) for i, lags in enumerate(self._lags.T): reg_lags[:, i] = np.mean(lag_array[:, lags[0]:lags[1]], 1) else: reg_lags = empty((nobs_orig, 0), dtype=np.float64) if self._x is not None: reg_x = self._x else: reg_x = empty((nobs_orig, 0), dtype=np.float64) self.regressors = np.hstack((reg_constant, reg_lags, reg_x)) first_obs, last_obs = self._indices self.regressors = self.regressors[first_obs:last_obs, :] self._y_adj = self._y[first_obs:last_obs]
def fit_scale(self, leading_indicator, cases, lag=0): """ Scaling correction for AR(p) model to fit case counts. Args: leading_indicator: Covariate that is a leading indicator for case counts cases (nd.array): 1-dimensional array containing case counts offset (int): Offset for window of cases counts you want to correct over """ self.lag = lag leading_mean = np.mean(leading_indicator) cases_mean = np.mean(cases) leading_std = np.std(leading_indicator) cases_std = np.std(cases) z = leading_indicator[:-lag - 1] x = cases[lag + 1:] p = self.p n = z.shape[0] self.beta[0] += -leading_mean * cases_std / leading_std + cases_mean self.beta[1:] *= cases_std / leading_std Z = np.hstack([tf.ones((n, 1)), lagmat(z, maxlag=p)])[p:] x_pred = Z @ self.beta.T self.scale = np.sum(x) / np.sum(x_pred)
def infer_discrete_state_transition_from_training_data(is_non_local, penalty=1e-5): data = pd.DataFrame({ 'is_non_local': is_non_local.astype(np.float64), 'lagged_is_non_local': lagmat(is_non_local, maxlag=1).astype(np.float64).squeeze(), }).dropna() MODEL_FORMULA = 'is_non_local ~ 1 + lagged_is_non_local' response, design_matrix = dmatrices(MODEL_FORMULA, data) penalty = np.ones((design_matrix.shape[1], )) * penalty penalty[0] = 0.0 fit = penalized_IRLS(design_matrix, response, family=families.Binomial(), penalty=penalty) predict_data = { 'lagged_is_non_local': np.asarray([0, 1]), } predict_design_matrix = build_design_matrices( [design_matrix.design_info], predict_data, NA_action=NAAction(NA_types=[]))[0] non_local_probability = families.Binomial().link.inverse( predict_design_matrix @ np.squeeze(fit.coefficients)) non_local_probability[np.isnan(non_local_probability)] = 0.0 return np.asarray( [[1 - non_local_probability[0], non_local_probability[0]], [1 - non_local_probability[1], non_local_probability[1]]])
def my_AR(endog, maxlag, trend=None): """ Autoregressive model implementation, aka AR(p) :param endog: the dependent variables :param maxlag: maximum number of lags to use :param trend: 'c': add constant, 'nc' or None: no constant :return: my_OLS dictionary See ref: http://statsmodels.sourceforge.net/stable/_modules/statsmodels/tsa/ar_model.html#AR """ # Dependent data matrix Y = endog[maxlag:] # has observations for the fit p lags removed # Explanatory data matrix X = lagmat(endog, maxlag, trim='both') if trend is not None: X = add_trend( X, prepend=True, trend=trend) # prepends puts trend column at the beginning result = my_OLS(Y, X) result['maxlag'] = maxlag # Akaike information criterion using statsmodel def for AR(p) (Lutkephol's definition) # note this is diff to adfuller's def result['aic'] = np.log( result['sigma']) + 2.0 * (1.0 + result['df_model']) / result['nobs'] return result
def VAR_forecast(Vector, VAR_estimates, lag_order, horizon, shock=None): """ Inputs the VAR Vector, VAR estimates, the lag order of the model, the forecast horizon, and the desired first period shock. Args: Returns: """ # Initial Period shock for IRF. if shock is None: shock = np.zeros(len(Vector[0])) error = np.zeros((len(Vector), len(Vector[0]))) error[0] = shock # Predictions for Forecast Horizon. for t in np.arange(0, horizon): X_hat = Vector for i in range(1, lag_order): # X_hat = np.column_stack([X_hat, lag(Vector, i)]) lagged_vector = tsatools.lagmat(Vector, maxlag=1) X_hat = np.column_stack([X_hat, lagged_vector]) X_hat = sm.add_constant(X_hat) Y_hat = [] for Eq in VAR_estimates: Y_hat.append(np.dot(X_hat[-1], VAR_estimates[Eq].params)) Forecast = Y_hat + error[t] Vector = np.vstack((Vector, Forecast)) return Vector[-horizon:]
def _df_select_lags(y, trend, max_lags, method): """ Helper method to determine the best lag length in DF-like regressions Parameters ---------- y : array-like, (nobs,) The data for the lag selection exercise trend : str, {'nc','c','ct','ctt'} The trend order max_lags : int The maximum number of lags to check. This setting affects all estimation since the sample is adjusted by max_lags when fitting the models method : str, {'AIC','BIC','t-stat'} The method to use when estimating the model Returns ------- best_ic : float The information criteria at the selected lag best_lag : int The selected lag all_res : list List of OLS results from fitting max_lag + 1 models Notes ----- See statsmodels.tsa.tsatools._autolag for details. If max_lags is None, the default value of 12 * (nobs/100)**(1/4) is used. """ nobs = y.shape[0] delta_y = diff(y) if max_lags is None: max_lags = int(ceil(12. * power(nobs / 100., 1 / 4.))) rhs = lagmat(delta_y[:, None], max_lags, trim='both', original='in') nobs = rhs.shape[0] rhs[:, 0] = y[-nobs - 1:-1] # replace 0 with level of y lhs = delta_y[-nobs:] if trend != 'nc': full_rhs = add_trend(rhs, trend, prepend=True) else: full_rhs = rhs start_lag = full_rhs.shape[1] - rhs.shape[1] + 1 ic_best, best_lag, all_res = _autolag(OLS, lhs, full_rhs, start_lag, max_lags, method, regresults=True) # To get the correct number of lags, subtract the start_lag since # lags 0,1,...,start_lag-1 were not actual lags, but other variables best_lag -= start_lag return ic_best, best_lag, all_res
def _df_select_lags(y, trend, max_lags, method, low_memory=False): """ Helper method to determine the best lag length in DF-like regressions Parameters ---------- y : ndarray The data for the lag selection exercise trend : {'nc','c','ct','ctt'} The trend order max_lags : int The maximum number of lags to check. This setting affects all estimation since the sample is adjusted by max_lags when fitting the models method : {'AIC','BIC','t-stat'} The method to use when estimating the model low_memory : bool Flag indicating whether to use the low-memory algorithm for lag-length selection. Returns ------- best_ic : float The information criteria at the selected lag best_lag : int The selected lag Notes ----- If max_lags is None, the default value of 12 * (nobs/100)**(1/4) is used. """ nobs = y.shape[0] # This is the absolute maximum number of lags possible, # only needed to very short time series. max_max_lags = nobs // 2 - 1 if trend != 'nc': max_max_lags -= len(trend) if max_lags is None: max_lags = int(ceil(12. * power(nobs / 100., 1 / 4.))) max_lags = max(min(max_lags, max_max_lags), 0) if low_memory: out = _autolag_ols_low_memory(y, max_lags, trend, method) return out delta_y = diff(y) rhs = lagmat(delta_y[:, None], max_lags, trim='both', original='in') nobs = rhs.shape[0] rhs[:, 0] = y[-nobs - 1:-1] # replace 0 with level of y lhs = delta_y[-nobs:] if trend != 'nc': full_rhs = add_trend(rhs, trend, prepend=True) else: full_rhs = rhs start_lag = full_rhs.shape[1] - rhs.shape[1] + 1 ic_best, best_lag = _autolag_ols(lhs, full_rhs, start_lag, max_lags, method) return ic_best, best_lag
def _tsls_arima(self, x, arlags, model): """ Two-stage least squares approach for estimating ARIMA(p, 1, 1) parameters as an alternative to MLE estimation in the case of solver non-convergence Parameters ---------- x : array_like data series arlags : int AR(p) order model : {'c','ct'} Constant and trend order to include in regression * 'c' : constant only * 'ct' : constant and trend Returns ------- arparams : int AR(1) coefficient plus constant theta : int MA(1) coefficient olsfit.resid : ndarray residuals from second-stage regression """ endog = np.diff(x, axis=0) exog = lagmat(endog, arlags, trim='both') # add constant if requested if model == 'ct': exog = add_constant(exog) # remove extra terms from front of endog endog = endog[arlags:] if arlags > 0: resids = lagmat(OLS(endog, exog).fit().resid, 1, trim='forward') else: resids = lagmat(-endog, 1, trim='forward') # add negated residuals column to exog as MA(1) term exog = np.append(exog, -resids, axis=1) olsfit = OLS(endog, exog).fit() if model == 'ct': arparams = olsfit.params[1:(len(olsfit.params) - 1)] else: arparams = olsfit.params[0:(len(olsfit.params) - 1)] theta = olsfit.params[len(olsfit.params) - 1] return arparams, theta, olsfit.resid
def __init__(self, endog, k_regimes, order, trend='c', exog=None, exog_tvtp=None, switching_ar=True, switching_trend=True, switching_exog=False, switching_variance=False, dates=None, freq=None, missing='none'): # Properties self.switching_ar = switching_ar # Switching options if self.switching_ar is True or self.switching_ar is False: self.switching_ar = [self.switching_ar] * order elif not len(self.switching_ar) == order: raise ValueError('Invalid iterable passed to `switching_ar`.') # Initialize the base model super(MarkovAutoregression, self).__init__( endog, k_regimes, trend=trend, exog=exog, order=order, exog_tvtp=exog_tvtp, switching_trend=switching_trend, switching_exog=switching_exog, switching_variance=switching_variance, dates=dates, freq=freq, missing=missing) # Sanity checks if self.nobs <= self.order: raise ValueError('Must have more observations than the order of' ' the autoregression.') # Autoregressive exog self.exog_ar = lagmat(endog, self.order)[self.order:] # Reshape other datasets self.nobs -= self.order self.orig_endog = self.endog self.endog = self.endog[self.order:] if self._k_exog > 0: self.orig_exog = self.exog self.exog = self.exog[self.order:] # Reset the ModelData datasets self.data.endog, self.data.exog = ( self.data._convert_endog_exog(self.endog, self.exog)) # Reset indexes, if provided if self.data.row_labels is not None: self.data._cache['row_labels'] = ( self.data.row_labels[self.order:]) if self._index is not None: if self._index_generated: self._index = self._index[:-self.order] else: self._index = self._index[self.order:] # Parameters self.parameters['autoregressive'] = self.switching_ar # Cache an array for holding slices self._predict_slices = [slice(None, None, None)] * (self.order + 1)
def forecast(self, Phi, Sigma, h=12, y=None, append=True): if y is None: y = self.data y_base = y y0 = np.ones((self._ny * self._p + self._cons)) y0[:self._ny * self._p] = lagmat(y_base, self._p, 'none')[-self._p] yfcst = np.zeros((h, self._ny)) for i in range(h): yfcst[i] = np.dot(y0, Phi) y = np.vstack((y, yfcst[i])) if self._cons: y0[:-self._cons] = lagmat(y, self._p, 'none')[-self._p] else: y0 = lagmat(y, self._p, 'none')[-self._p] return yfcst
def moment_ret(self, theta_ret, theta_vol=None, uarg=None, zlag=1, **kwargs): """Moment conditions (returns) for spectral GMM estimator. Parameters ---------- theta_ret : (2, ) array Vector of model parameters. [phi, price_ret] theta_vol : (3, ) array Vector of model parameters. [mean, rho, delta] uarg : (nu, ) array Grid to evaluate a and b functions zlag : int Number of lags to use for the instrument Returns ------- moment : (nobs, nmoms) array Matrix of momcond restrictions Raises ------ ValueError """ if uarg is None: raise ValueError("uarg is missing!") vollag, vol = lagmat(self.vol, maxlag=zlag, original='sep', trim='both') # Number of observations after truncation nobs = vol.shape[0] # Number of moments nmoms = 2 * uarg.shape[0] * (zlag+1) # Change class attribute with the current theta param = ARGparams() try: param.update(theta_ret=theta_ret, theta_vol=theta_vol) except ValueError: return np.ones((nobs, nmoms))*1e10 # Must be (nobs, nu) array try: cfun = self.char_fun_ret(uarg, param)[zlag-1:] except ValueError: return np.ones((nobs, nmoms))*1e10 # Must be (nobs, nu) array error = np.exp(-self.ret[zlag:, np.newaxis] * uarg) - cfun # Instruments, (nobs, ninstr) array instr = np.hstack([np.exp(-1j * vollag), np.ones((nobs, 1))]) # Must be (nobs, nmoms) array moment = error[:, np.newaxis, :] * instr[:, :, np.newaxis] moment = moment.reshape((nobs, nmoms//2)) # (nobs, 2 * ninstr) moment = np.hstack([np.real(moment), np.imag(moment)]) return moment
def fit_discrete_state_transition_no_speed(speed, is_replay, penalty=1E-5, speed_knots=None, diagonal=None): """Estimate the predicted probablity of replay and whether it was a replay in the previous time step. p(I_t | I_t-1, v_t-1) p_I_0, p_I_1 in Long Tao's code Parameters ---------- speed : ndarray, shape (n_time,) is_replay : boolean ndarray, shape (n_time,) speed_knots : ndarray, shape (n_knots,) Returns ------- probability_replay : ndarray, shape (n_time, 2) """ data = pd.DataFrame({ 'is_replay': is_replay.astype(np.float64), 'lagged_is_replay': lagmat(is_replay, maxlag=1).astype(np.float64).squeeze(), 'lagged_speed': lagmat(speed, maxlag=1).squeeze() }).dropna() MODEL_FORMULA = 'is_replay ~ 1 + lagged_is_replay' response, design_matrix = dmatrices(MODEL_FORMULA, data) penalty = np.ones((design_matrix.shape[1], )) * penalty penalty[0] = 0.0 fit = penalized_IRLS(design_matrix, response, family=FAMILY, penalty=penalty) return partial(predict_probability, design_matrix=design_matrix, coefficients=fit.coefficients)
def _stackX(self, k_ar, trend): """ Private method to build the RHS matrix for estimation. Columns are trend terms then lags. """ endog = self.endog X = lagmat(endog, maxlag=k_ar, trim='both') k_trend = util.get_trendorder(trend) if k_trend: X = add_trend(X, prepend=True, trend=trend) self.k_trend = k_trend return X
def _df_select_lags(y, trend, max_lags, method): """ Helper method to determine the best lag length in DF-like regressions Parameters ---------- y : array The data for the lag selection exercise trend : {'nc','c','ct','ctt'} The trend order max_lags : int The maximum number of lags to check. This setting affects all estimation since the sample is adjusted by max_lags when fitting the models method : {'AIC','BIC','t-stat'} The method to use when estimating the model Returns ------- best_ic : float The information criteria at the selected lag best_lag : int The selected lag Notes ----- If max_lags is None, the default value of 12 * (nobs/100)**(1/4) is used. """ nobs = y.shape[0] delta_y = diff(y) if max_lags is None: max_lags = int(ceil(12. * power(nobs / 100., 1 / 4.))) rhs = lagmat(delta_y[:, None], max_lags, trim='both', original='in') nobs = rhs.shape[0] rhs[:, 0] = y[-nobs - 1:-1] # replace 0 with level of y lhs = delta_y[-nobs:] if trend != 'nc': full_rhs = add_trend(rhs, trend, prepend=True) else: full_rhs = rhs start_lag = full_rhs.shape[1] - rhs.shape[1] + 1 ic_best, best_lag = _autolag_ols(lhs, full_rhs, start_lag, max_lags, method) return ic_best, best_lag
def fit(self, nlags): '''estimate parameters using ols Parameters ---------- nlags : integer number of lags to include in regression, same for all variables Returns ------- None, but attaches arhat : array (nlags, nvar, nvar) full lag polynomial array arlhs : array (nlags-1, nvar, nvar) reduced lag polynomial for left hand side other statistics as returned by linalg.lstsq : need to be completed This currently assumes all parameters are estimated without restrictions. In this case SUR is identical to OLS estimation results are attached to the class instance ''' self.nlags = nlags # without current period nvars = self.nvars #TODO: ar2s looks like a module variable, bug? #lmat = lagmat(ar2s, nlags, trim='both', original='in') lmat = lagmat(self.y, nlags, trim='both', original='in') self.yred = lmat[:,:nvars] self.xred = lmat[:,nvars:] res = np.linalg.lstsq(self.xred, self.yred, rcond=-1) self.estresults = res self.arlhs = res[0].reshape(nlags, nvars, nvars) self.arhat = ar2full(self.arlhs) self.rss = res[1] self.xredrank = res[2]
def _em_autoregressive(self, result, betas, tmp=None): """ EM step for autoregressive coefficients and variances """ if tmp is None: tmp = np.sqrt(result.smoothed_marginal_probabilities) resid = np.zeros((self.k_regimes, self.nobs + self.order)) resid[:] = self.orig_endog if self._k_exog > 0: for i in range(self.k_regimes): resid[i] -= np.dot(self.orig_exog, betas[i]) # The difference between this and `_em_exog` is that here we have a # different endog and exog for each regime coeffs = np.zeros((self.k_regimes,) + (self.order,)) variance = np.zeros((self.k_regimes,)) exog = np.zeros((self.nobs, self.order)) for i in range(self.k_regimes): endog = resid[i, self.order:] exog = lagmat(resid[i], self.order)[self.order:] tmp_endog = tmp[i] * endog tmp_exog = tmp[i][:, None] * exog coeffs[i] = np.dot(np.linalg.pinv(tmp_exog), tmp_endog) if self.switching_variance: tmp_resid = endog - np.dot(exog, coeffs[i]) variance[i] = (np.sum( tmp_resid**2 * result.smoothed_marginal_probabilities[i]) / np.sum(result.smoothed_marginal_probabilities[i])) else: tmp_resid = tmp_endog - np.dot(tmp_exog, coeffs[i]) variance[i] = np.sum(tmp_resid**2) # Variances if not self.switching_variance: variance = variance.sum() / self.nobs return coeffs, variance
def fnn(data, maxm): """ Compute the embedding dimension of a time series data to build the phase space using the false neighbors criterion data--> time series maxm--> maximmum embeding dimension """ RT=15.0 AT=2 sigmay=np.std(data, ddof=1) nyr=len(data) m=maxm EM=lagmat(data, maxlag=m-1) EEM=np.asarray([EM[j,:] for j in range(m-1, EM.shape[0])]) embedm=maxm for k in range(AT,EEM.shape[1]+1): fnn1=[] fnn2=[] Ma=EEM[:,range(k)] D=dist(Ma) for i in range(1,EEM.shape[0]-m-k): #print D.shape #print(D[i,range(i-1)]) d=D[i,:] pdnz=np.where(d>0) dnz=d[pdnz] Rm=np.min(dnz) l=np.where(d==Rm) l=l[0] l=l[len(l)-1] if l+m+k-1<nyr: fnn1.append(np.abs(data[i+m+k-1]-data[l+m+k-1])/Rm) fnn2.append(np.abs(data[i+m+k-1]-data[l+m+k-1])/sigmay) Ind1=np.where(np.asarray(fnn1)>RT) Ind2=np.where(np.asarray(fnn2)>AT) if len(Ind1[0])/float(len(fnn1))<0.1 and len(Ind2[0])/float(len(fnn2))<0.1: embedm=k break return embedm
[ 0.1, -0.1]]]) a31 = np.r_[np.eye(3)[None,:,:], 0.8*np.eye(3)[None,:,:]] a32 = np.array([[[ 1. , 0. , 0. ], [ 0. , 1. , 0. ], [ 0. , 0. , 1. ]], [[ 0.8, 0. , 0. ], [ 0.1, 0.6, 0. ], [ 0. , 0. , 0.9]]]) ######## ut = np.random.randn(1000,2) ar2s = vargenerate(a22,ut) #res = np.linalg.lstsq(lagmat(ar2s,1)[:,1:], ar2s) res = np.linalg.lstsq(lagmat(ar2s,1), ar2s) bhat = res[0].reshape(1,2,2) arhat = ar2full(bhat) #print(maxabs(arhat - a22) v = _Var(ar2s) v.fit(1) v.forecast() v.forecast(25)[-30:] ar23 = np.array([[[ 1. , 0. ], [ 0. , 1. ]], [[-0.6, 0. ],
def acorr_lm(x, maxlag=None, autolag='AIC', store=False, regresults=False): '''Lagrange Multiplier tests for autocorrelation This is a generic Lagrange Multiplier test for autocorrelation. I don't have a reference for it, but it returns Engle's ARCH test if x is the squared residual array. A variation on it with additional exogenous variables is the Breusch-Godfrey autocorrelation test. Parameters ---------- resid : ndarray, (nobs,) residuals from an estimation, or time series maxlag : int highest lag to use autolag : None or string If None, then a fixed number of lags given by maxlag is used. store : bool If true then the intermediate results are also returned Returns ------- lm : float Lagrange multiplier test statistic lmpval : float p-value for Lagrange multiplier test fval : float fstatistic for F test, alternative version of the same test based on F test for the parameter restriction fpval : float pvalue for F test resstore : instance (optional) a class instance that holds intermediate results. Only returned if store=True See Also -------- het_arch acorr_breusch_godfrey acorr_ljung_box ''' if regresults: store = True x = np.asarray(x) nobs = x.shape[0] if maxlag is None: #for adf from Greene referencing Schwert 1989 maxlag = int(np.ceil(12. * np.power(nobs/100., 1/4.)))#nobs//4 #TODO: check default, or do AIC/BIC xdiff = np.diff(x) # xdall = lagmat(x[:,None], maxlag, trim='both') nobs = xdall.shape[0] xdall = np.c_[np.ones((nobs,1)), xdall] xshort = x[-nobs:] if store: resstore = ResultsStore() if autolag: #search for lag length with highest information criteria #Note: I use the same number of observations to have comparable IC results = {} for mlag in range(1, maxlag+1): results[mlag] = OLS(xshort, xdall[:,:mlag+1]).fit() if autolag.lower() == 'aic': bestic, icbestlag = min((v.aic,k) for k,v in iteritems(results)) elif autolag.lower() == 'bic': icbest, icbestlag = min((v.bic,k) for k,v in iteritems(results)) else: raise ValueError("autolag can only be None, 'AIC' or 'BIC'") #rerun ols with best ic xdall = lagmat(x[:,None], icbestlag, trim='both') nobs = xdall.shape[0] xdall = np.c_[np.ones((nobs,1)), xdall] xshort = x[-nobs:] usedlag = icbestlag if regresults: resstore.results = results else: usedlag = maxlag resols = OLS(xshort, xdall[:,:usedlag+1]).fit() fval = resols.fvalue fpval = resols.f_pvalue lm = nobs * resols.rsquared lmpval = stats.chi2.sf(lm, usedlag) # Note: degrees of freedom for LM test is nvars minus constant = usedlags #return fval, fpval, lm, lmpval if store: resstore.resols = resols resstore.usedlag = usedlag return lm, lmpval, fval, fpval, resstore else: return lm, lmpval, fval, fpval
def acorr_breusch_godfrey(results, nlags=None, store=False): '''Breusch Godfrey Lagrange Multiplier tests for residual autocorrelation Parameters ---------- results : Result instance Estimation results for which the residuals are tested for serial correlation nlags : int Number of lags to include in the auxiliary regression. (nlags is highest lag) store : bool If store is true, then an additional class instance that contains intermediate results is returned. Returns ------- lm : float Lagrange multiplier test statistic lmpval : float p-value for Lagrange multiplier test fval : float fstatistic for F test, alternative version of the same test based on F test for the parameter restriction fpval : float pvalue for F test resstore : instance (optional) a class instance that holds intermediate results. Only returned if store=True Notes ----- BG adds lags of residual to exog in the design matrix for the auxiliary regression with residuals as endog, see Greene 12.7.1. References ---------- Greene Econometrics, 5th edition ''' x = np.asarray(results.resid) exog_old = results.model.exog nobs = x.shape[0] if nlags is None: #for adf from Greene referencing Schwert 1989 nlags = np.trunc(12. * np.power(nobs/100., 1/4.))#nobs//4 #TODO: check default, or do AIC/BIC nlags = int(nlags) x = np.concatenate((np.zeros(nlags), x)) #xdiff = np.diff(x) # xdall = lagmat(x[:,None], nlags, trim='both') nobs = xdall.shape[0] xdall = np.c_[np.ones((nobs,1)), xdall] xshort = x[-nobs:] exog = np.column_stack((exog_old, xdall)) k_vars = exog.shape[1] if store: resstore = ResultsStore() resols = OLS(xshort, exog).fit() ft = resols.f_test(np.eye(nlags, k_vars, k_vars - nlags)) fval = ft.fvalue fpval = ft.pvalue fval = np.squeeze(fval)[()] #TODO: fix this in ContrastResults fpval = np.squeeze(fpval)[()] lm = nobs * resols.rsquared lmpval = stats.chi2.sf(lm, nlags) # Note: degrees of freedom for LM test is nvars minus constant = usedlags #return fval, fpval, lm, lmpval if store: resstore.resols = resols resstore.usedlag = nlags return lm, lmpval, fval, fpval, resstore else: return lm, lmpval, fval, fpval
def adfuller(x, maxlag=None, regression="c", autolag='AIC', store=False, regresults=False): """ Augmented Dickey-Fuller unit root test The Augmented Dickey-Fuller test can be used to test for a unit root in a univariate process in the presence of serial correlation. Parameters ---------- x : array_like, 1d data series maxlag : int Maximum lag which is included in test, default 12*(nobs/100)^{1/4} regression : {'c','ct','ctt','nc'} Constant and trend order to include in regression * 'c' : constant only (default) * 'ct' : constant and trend * 'ctt' : constant, and linear and quadratic trend * 'nc' : no constant, no trend autolag : {'AIC', 'BIC', 't-stat', None} * if None, then maxlag lags are used * if 'AIC' (default) or 'BIC', then the number of lags is chosen to minimize the corresponding information criterion * 't-stat' based choice of maxlag. Starts with maxlag and drops a lag until the t-statistic on the last lag length is significant using a 5%-sized test store : bool If True, then a result instance is returned additionally to the adf statistic. Default is False regresults : bool, optional If True, the full regression results are returned. Default is False Returns ------- adf : float Test statistic pvalue : float MacKinnon's approximate p-value based on MacKinnon (1994, 2010) usedlag : int Number of lags used nobs : int Number of observations used for the ADF regression and calculation of the critical values critical values : dict Critical values for the test statistic at the 1 %, 5 %, and 10 % levels. Based on MacKinnon (2010) icbest : float The maximized information criterion if autolag is not None. resstore : ResultStore, optional A dummy class with results attached as attributes Notes ----- The null hypothesis of the Augmented Dickey-Fuller is that there is a unit root, with the alternative that there is no unit root. If the pvalue is above a critical size, then we cannot reject that there is a unit root. The p-values are obtained through regression surface approximation from MacKinnon 1994, but using the updated 2010 tables. If the p-value is close to significant, then the critical values should be used to judge whether to reject the null. The autolag option and maxlag for it are described in Greene. Examples -------- See example notebook References ---------- .. [1] W. Green. "Econometric Analysis," 5th ed., Pearson, 2003. .. [2] Hamilton, J.D. "Time Series Analysis". Princeton, 1994. .. [3] MacKinnon, J.G. 1994. "Approximate asymptotic distribution functions for unit-root and cointegration tests. `Journal of Business and Economic Statistics` 12, 167-76. .. [4] MacKinnon, J.G. 2010. "Critical Values for Cointegration Tests." Queen's University, Dept of Economics, Working Papers. Available at http://ideas.repec.org/p/qed/wpaper/1227.html """ if regresults: store = True trenddict = {None: 'nc', 0: 'c', 1: 'ct', 2: 'ctt'} if regression is None or isinstance(regression, (int, long)): regression = trenddict[regression] regression = regression.lower() if regression not in ['c', 'nc', 'ct', 'ctt']: raise ValueError("regression option %s not understood") % regression x = np.asarray(x) nobs = x.shape[0] if maxlag is None: #from Greene referencing Schwert 1989 maxlag = int(np.ceil(12. * np.power(nobs / 100., 1 / 4.))) xdiff = np.diff(x) xdall = lagmat(xdiff[:, None], maxlag, trim='both', original='in') nobs = xdall.shape[0] # pylint: disable=E1103 xdall[:, 0] = x[-nobs - 1:-1] # replace 0 xdiff with level of x xdshort = xdiff[-nobs:] if store: resstore = ResultsStore() if autolag: if regression != 'nc': fullRHS = add_trend(xdall, regression, prepend=True) else: fullRHS = xdall startlag = fullRHS.shape[1] - xdall.shape[1] + 1 # 1 for level # pylint: disable=E1103 #search for lag length with smallest information criteria #Note: use the same number of observations to have comparable IC #aic and bic: smaller is better if not regresults: icbest, bestlag = _autolag(OLS, xdshort, fullRHS, startlag, maxlag, autolag) else: icbest, bestlag, alres = _autolag(OLS, xdshort, fullRHS, startlag, maxlag, autolag, regresults=regresults) resstore.autolag_results = alres bestlag -= startlag # convert to lag not column index #rerun ols with best autolag xdall = lagmat(xdiff[:, None], bestlag, trim='both', original='in') nobs = xdall.shape[0] # pylint: disable=E1103 xdall[:, 0] = x[-nobs - 1:-1] # replace 0 xdiff with level of x xdshort = xdiff[-nobs:] usedlag = bestlag else: usedlag = maxlag icbest = None if regression != 'nc': resols = OLS(xdshort, add_trend(xdall[:, :usedlag + 1], regression)).fit() else: resols = OLS(xdshort, xdall[:, :usedlag + 1]).fit() adfstat = resols.tvalues[0] # adfstat = (resols.params[0]-1.0)/resols.bse[0] # the "asymptotically correct" z statistic is obtained as # nobs/(1-np.sum(resols.params[1:-(trendorder+1)])) (resols.params[0] - 1) # I think this is the statistic that is used for series that are integrated # for orders higher than I(1), ie., not ADF but cointegration tests. # Get approx p-value and critical values pvalue = mackinnonp(adfstat, regression=regression, N=1) critvalues = mackinnoncrit(N=1, regression=regression, nobs=nobs) critvalues = {"1%" : critvalues[0], "5%" : critvalues[1], "10%" : critvalues[2]} if store: resstore.resols = resols resstore.maxlag = maxlag resstore.usedlag = usedlag resstore.adfstat = adfstat resstore.critvalues = critvalues resstore.nobs = nobs resstore.H0 = ("The coefficient on the lagged level equals 1 - " "unit root") resstore.HA = "The coefficient on the lagged level < 1 - stationary" resstore.icbest = icbest resstore._str = 'Augmented Dickey-Fuller Test Results' return adfstat, pvalue, critvalues, resstore else: if not autolag: return adfstat, pvalue, usedlag, nobs, critvalues else: return adfstat, pvalue, usedlag, nobs, critvalues, icbest
def momcond_vol(self, theta_vol, uarg=None, zlag=1): """Moment conditions (volatility) for spectral GMM estimator. Parameters ---------- theta_vol : (3, ) array Vector of model parameters. [scale, rho, delta] uarg : (nu, ) array Grid to evaluate a and b functions zlag : int Number of lags to use for the instrument Returns ------- moment : (nobs, nmoms) array Matrix of momcond restrictions dmoment : (nmoms, nparams) array Gradient of momcond restrictions. Mean over observations Raises ------ ValueError """ if uarg is None: raise ValueError("uarg is missing!") vollag, vol = lagmat(self.vol, maxlag=zlag, original='sep', trim='both') prevvol = vollag[:, 0][:, np.newaxis] # Number of observations after truncation nobs = vol.shape[0] # Number of moments nmoms = 2 * uarg.shape[0] * (zlag+1) # Number of parameters nparams = theta_vol.shape[0] # Change class attribute with the current theta param = ARGparams() try: param.update(theta_vol=theta_vol) except ValueError: return np.ones((nobs, nmoms))*1e10, np.ones((nmoms, nparams))*1e10 # Must be (nobs, nu) array error = np.exp(-vol * uarg) - self.char_fun_vol(uarg, param)[zlag-1:] # Instruments, (nobs, ninstr) array instr = np.hstack([np.exp(-1j * vollag), np.ones((nobs, 1))]) # Must be (nobs, nmoms) array moment = error[:, np.newaxis, :] * instr[:, :, np.newaxis] moment = moment.reshape((nobs, nmoms//2)) # (nobs, 2 * ninstr) moment = np.hstack([np.real(moment), np.imag(moment)]) # Initialize derivative matrix dmoment = np.empty((nmoms, nparams)) for i in range(nparams): dexparg = - prevvol * self.dafun(uarg, param)[i] \ - np.ones((nobs, 1)) * self.dbfun(uarg, param)[i] derror = - self.char_fun_vol(uarg, param)[zlag-1:] * dexparg derrorinstr = derror[:, np.newaxis, :] * instr[:, :, np.newaxis] derrorinstr = derrorinstr.reshape((nobs, nmoms//2)) derrorinstr = np.hstack([np.real(derrorinstr), np.imag(derrorinstr)]) dmoment[:, i] = derrorinstr.mean(0) return moment, dmoment
max_xc = 0 best_shift = 0 for shift in range(-10, 0): #Tune this search range xc = (numpy.roll(sig1, shift) * sig2).sum() if xc > max_xc: max_xc = xc best_shift = shift print 'Best shift:', best_shift """ If best_shift is at the edges of your search range, you should expand the search range. """ ############################################################################# # create lag matrix for regression bpmat = tools.lagmat(x,lag, original='in') etmat = tools.lagmat(z,lag, original='in') lamat = numpy.column_stack([bpmat,etmat]) #for i in range(len(etmat)): # lagmat.append(bpmat[i]+etmat[i]) #transpose matrix to determine required length #run least squared regression sqrd = numpy.linalg.lstsq(bpmat,y) sqrdlag = numpy.linalg.lstsq(lamat,y) wlls = sqrd[0] lagls = sqrdlag[0] cumls = numpy.cumsum(wlls) lagcumls =numpy.cumsum(lagls)
def cointegration_johansen(input_df, lag=1): """ For axis: -1 means no deterministic part, 0 means constant term, 1 means constant plus time-trend, > 1 means higher order polynomial. :param input_df: the input vectors as a pandas.DataFrame instance :param lag: number of lagged difference terms used when computing the estimator :return: returns test statistics data """ count_samples, count_dimensions = input_df.shape input_df = detrend(input_df, type='constant', axis=0) diff_input_df = numpy.diff(input_df, 1, axis=0) z = tsatools.lagmat(diff_input_df, lag) z = z[lag:] z = detrend(z, type='constant', axis=0) diff_input_df = diff_input_df[lag:] diff_input_df = detrend(diff_input_df, type='constant', axis=0) r0t = residuals(diff_input_df, z) lx = input_df[:-lag] lx = lx[1:] diff_input_df = detrend(lx, type='constant', axis=0) rkt = residuals(diff_input_df, z) if rkt is None: return None skk = numpy.dot(rkt.T, rkt) / rkt.shape[0] sk0 = numpy.dot(rkt.T, r0t) / rkt.shape[0] s00 = numpy.dot(r0t.T, r0t) / r0t.shape[0] sig = numpy.dot(sk0, numpy.dot(linalg.inv(s00), sk0.T)) eigenvalues, eigenvectors = linalg.eig(numpy.dot(linalg.inv(skk), sig)) # normalizing the eigenvectors such that (du'skk*du) = I temp = linalg.inv(linalg.cholesky(numpy.dot(eigenvectors.T, numpy.dot(skk, eigenvectors)))) dt = numpy.dot(eigenvectors, temp) # sorting eigenvalues and vectors order_decreasing = numpy.flipud(numpy.argsort(eigenvalues)) sorted_eigenvalues = eigenvalues[order_decreasing] sorted_eigenvectors = dt[:, order_decreasing] # computing the trace and max eigenvalue statistics trace_statistics = numpy.zeros(count_dimensions) eigenvalue_statistics = numpy.zeros(count_dimensions) critical_values_max_eigenvalue = numpy.zeros((count_dimensions, 3)) critical_values_trace = numpy.zeros((count_dimensions, 3)) iota = numpy.ones(count_dimensions) t, junk = rkt.shape for i in range(0, count_dimensions): tmp = numpy.log(iota - sorted_eigenvalues)[i:] trace_statistics[i] = -t * numpy.sum(tmp, 0) eigenvalue_statistics[i] = -t * numpy.log(1 - sorted_eigenvalues[i]) critical_values_max_eigenvalue[i, :] = get_critical_values_max_eigenvalue(count_dimensions - i, time_polynomial_order=0) critical_values_trace[i, :] = get_critical_values_trace(count_dimensions - i, time_polynomial_order=0) order_decreasing[i] = i result = dict() result['rkt'] = rkt result['r0t'] = r0t result['eigenvalues'] = sorted_eigenvalues result['eigenvectors'] = sorted_eigenvectors result['trace_statistic'] = trace_statistics # likelihood ratio trace statistic result['eigenvalue_statistics'] = eigenvalue_statistics # maximum eigenvalue statistic result['critical_values_trace'] = critical_values_trace result['critical_values_max_eigenvalue'] = critical_values_max_eigenvalue result['order_decreasing'] = order_decreasing # indices of eigenvalues in decreasing order return result
Trans_M2 = curv(delt_M2,P_M2,r) Trans_O1 = curv(delt_O1,P_O1,r) tf=time.clock() print '...Done!',tf-t0, 'seconds' t0=time.clock ########################################################################### # Calculate BP Response Function ########################################################################### ti=time.clock() # measure time of calculation print 'Calculating BP Response function...', t0=time.clock() # create lag matrix for regression bpmat = tools.lagmat(dbp, lag, original='in') etmat = tools.lagmat(ddl, lag, original='in') #lamat combines lag matrices of bp and et lamat = numpy.column_stack([bpmat,etmat]) #for i in range(len(etmat)): # lagmat.append(bpmat[i]+etmat[i]) #transpose matrix to determine required length #run least squared regression sqrd = numpy.linalg.lstsq(bpmat,dwl) #determine lag coefficients of the lag matrix lamat sqrdlag = numpy.linalg.lstsq(lamat,dwl) wlls = sqrd[0] #lagls return the coefficients of the least squares of lamat lagls = sqrdlag[0]
[ 0.1, -0.1]]]) a31 = np.r_[np.eye(3)[None,:,:], 0.8*np.eye(3)[None,:,:]] a32 = np.array([[[ 1. , 0. , 0. ], [ 0. , 1. , 0. ], [ 0. , 0. , 1. ]], [[ 0.8, 0. , 0. ], [ 0.1, 0.6, 0. ], [ 0. , 0. , 0.9]]]) ######## ut = np.random.randn(1000,2) ar2s = vargenerate(a22,ut) #res = np.linalg.lstsq(lagmat(ar2s,1)[:,1:], ar2s) res = np.linalg.lstsq(lagmat(ar2s,1), ar2s, rcond=-1) bhat = res[0].reshape(1,2,2) arhat = ar2full(bhat) #print(maxabs(arhat - a22) v = _Var(ar2s) v.fit(1) v.forecast() v.forecast(25)[-30:] ar23 = np.array([[[ 1. , 0. ], [ 0. , 1. ]], [[-0.6, 0. ], [ 0.2, -0.6]],
def tideproc(inpfile,bpdata,edata): delta = 1.1562 p = 7.692E5 ########################################################################### """ INPUT FILES ARE PUT IN BELOW """ lag = 100 tol = 0.05 #percentage of variance in frequency allowed; default is 2% r = 1 #well radius in inches Be = 0.10 #barometric efficiency numb = 2000 # number of values to process spd = 24 #samples per day hourly sampling = 24 lagt = -6.0 #hours different from UTC (negative indicates west); UT is -7 """ INPUT FILES END HERE """ ########################################################################### #frequencies in cpd O1 = 0.9295 #principal lunar K1 = 1.0029 #Lunar Solar M2 = 1.9324 #principal lunar S2 = 2.00 #Principal Solar N2 = 1.8957 #Lunar elliptic #periods in days P_M2 = 0.5175 P_O1 = 1.0758 # amplitude factors from Merritt 2004 b_O1 = 0.377 b_P1 = 0.176 b_K1 = 0.531 b_N2 = 0.174 b_M2 = 0.908 b_S2 = 0.423 b_K2 = 0.115 #love numbers and other constants from Agnew 2007 l = 0.0839 k = 0.2980 h = 0.6032 Km = 1.7618 #general lunar coefficient pi = math.pi #pi #gravity and earth radius g = 9.821 #m/s**2 a = 6.3707E6 #m g_ft = 32.23 #ft a_ft = 2.0902e7 #ft/s**2 #values to determine porosity from Merritt 2004 pg 56 Beta = 2.32E-8 rho = 62.4 impfile = inpfile outfile = 'c'+impfile data = csv.reader(open(impfile, 'rb'), delimiter=",") dy, u, l, nm, d, wl, t, vert =[], [], [], [], [], [], [], [] yrdty, year, month, day, hours, minutes, seconds, julday = [], [], [], [], [], [], [], [] yrdty2,year2, month2, day2, hours2, minutes2, seconds2, julday2 = [], [], [], [], [], [], [], [] yrdty3,year3, month3, day3, hours3, minutes3, seconds3, julday3 = [], [], [], [], [], [], [], [] # read in bp data bpdata = bpdata bdata = csv.reader(open(bpdata, 'rb'), delimiter=",") v, d2, bp=[], [], [] d3, SG33WDD, PW19S2, PW19M2, MXSWDD = [],[],[],[],[] etdata = edata #assign data in csv to arrays for row in data: u.append(row) for row in bdata: v.append(row) #pick well name, lat., long., and elevation data out of header of wl file well_name = u[0][1] lon = [float(u[5][1])] latt = [round(float(u[4][1]),3)] el = [round(float(u[10][1])/3.2808,3)] #import the bp data with open(bpdata, 'rb') as tot: csvreader1 = csv.reader(tot) for row in skip_first(csvreader1, 3): d2.append(row[2]) bp.append(float(row[3])) #import the wl data with open(impfile, 'rb') as total: csvreader = csv.reader(total) for row in skip_first(csvreader, 62): dy.append(row[0]) nm.append(row[1]) #import supplemental earth tide data with open(etdata, 'rb') as tos: csvreader2 = csv.reader(tos) for row in skip_first(csvreader2,2): d3.append(row[5]) SG33WDD.append(float(row[6])) PW19S2.append(row[7]) PW19M2.append(row[8]) MXSWDD.append(row[9]) #import a smaller part of the wl data for i in range(len(dy)-numb,len(dy)): d.append(dy[i]) wl.append(nm[i]) #fill in last line of wl data wl[-1]=wl[-2] for i in range(len(wl)): if wl[i] is '': wl[i]=wl[i-1] #create a list of latitude, longitude, elevation, and gmt for tidal calculation lat = latt*len(d) longit = lon*len(d) elev = el*len(d) gmtt = [float(lagt)]*len(d) # define the various components of the date, represented by d # dates for wl data for i in range(len(d)): yrdty.append(time.strptime(d[i],"%Y-%m-%d %H:%M:%S")) year.append(int(yrdty[i].tm_year)) month.append(int(yrdty[i].tm_mon)) day.append(int(yrdty[i].tm_mday)) hours.append(int(yrdty[i].tm_hour)) minutes.append(int(yrdty[i].tm_min)) seconds.append(int(0)) #yrdty[i].tm_sec # dates for bp data for i in range(len(d2)): yrdty2.append(time.strptime(d2[i],"%Y-%m-%d %H:%M:%S")) year2.append(int(yrdty2[i].tm_year)) month2.append(int(yrdty2[i].tm_mon)) day2.append(int(yrdty2[i].tm_mday)) hours2.append(int(yrdty2[i].tm_hour)) minutes2.append(int(yrdty2[i].tm_min)) seconds2.append(int(0)) #yrdty2[i].tm_sec # dates for bp data for i in range(len(d3)): yrdty3.append(time.strptime(d3[i],"%m/%d/%Y %H:%M")) year3.append(int(yrdty3[i].tm_year)) month3.append(int(yrdty3[i].tm_mon)) day3.append(int(yrdty3[i].tm_mday)) hours3.append(int(yrdty3[i].tm_hour)) minutes3.append(int(yrdty3[i].tm_min)) seconds3.append(int(0)) #yrdty2[i].tm_sec #julian day calculation def calc_jday(Y, M, D, h, m, s): # Y is year, M is month, D is day # h is hour, m is minute, s is second # returns decimal day (float) Months = [0, 31, 61, 92, 122, 153, 184, 214, 245, 275, 306, 337] if M < 3: Y = Y-1 M = M+12 JD = math.floor((Y+4712)/4.0)*1461 + ((Y+4712)%4)*365 JD = JD + Months[M-3] + D JD = JD + (h + (m/60.0) + (s/3600.0)) / 24.0 # corrections- # 59 accounts for shift of year from 1 Jan to 1 Mar # -13 accounts for shift between Julian and Gregorian calendars # -0.5 accounts for shift between noon and prev. midnight JD = JD + 59 - 13.5 return JD # create a list of julian dates for i in range(len(d)): julday.append(calc_jday(year[i],month[i],day[i],hours[i],minutes[i],seconds[i])) for i in range(len(d2)): julday2.append(calc_jday(year2[i],month2[i],day2[i],hours2[i],minutes2[i],seconds2[i])) for i in range(len(d3)): julday3.append(calc_jday(year3[i],month3[i],day3[i],hours3[i],minutes3[i],seconds3[i])) #run tidal function for i in range(len(d)): t.append(tamura.tide(int(year[i]), int(month[i]), int(day[i]), int(hours[i]), int(minutes[i]), int(seconds[i]), float(longit[i]), float(lat[i]), float(elev[i]), 0.0, lagt)) #float(gmtt[i]) vert, Grav_tide, WDD_tam, areal, potential, dilation = [], [], [], [], [], [] #determine vertical strain from Agnew 2007 #units are in sec squared, meaning results in mm # areal determine areal strain from Agnew 2007, units in mm #dilation from relationship defined using Harrison's code #WDD is used to recreate output from TSoft for i in range(len(t)): areal.append(t[i]*p*1E-5) potential.append(-318.49681664*t[i] - 0.50889238) WDD_tam.append(t[i]*(-.99362956469)-7.8749754) dilation.append(0.381611837*t[i] - 0.000609517) vert.append(t[i] * 1.692) Grav_tide.append(-1*t[i]) #convert to excel date-time numeric format xls_date = [] for i in range(len(d)): xls_date.append(float(julday[i])-2415018.5) xls_date2 = [] for i in range(len(d2)): xls_date2.append(float(julday2[i])-2415018.5) xls_date3 = [] for i in range(len(d3)): xls_date3.append(float(julday3[i])-2415018.5) t_start = xls_date[0] t_end = xls_date[-1] t_len = (len(xls_date)) #align bp data with wl data t1 = numpy.linspace(t_start, t_end, t_len) bpint = numpy.interp(t1, xls_date2, bp) etint = numpy.interp(t1, xls_date3, SG33WDD) xprep, yprep, zprep = [], [], [] #convert text from csv to float values for i in range(len(julday)): xprep.append(float(julday[i])) yprep.append(float(dilation[i])) zprep.append(float(wl[i])) #put data into numpy arrays for analysis xdata = numpy.array(xprep) ydata = numpy.array(yprep) zdata = numpy.array(zprep) bpdata = numpy.array(bpint) etdata = numpy.array(etint) bp = bpdata z = zdata y = ydata # tempdata = numpy.array(tempint) #standarize julian day to start at zero x0data = xdata - xdata[0] wl_z = [] mn = numpy.mean(z) std = numpy.std(z) for i in range(len(z)): wl_z.append((z[i]-mn)/std) bp_z = [] mn = numpy.mean(bp) std = numpy.std(bp) for i in range(len(bp)): bp_z.append((bp[i]-mn)/std) t_z = [] mn = numpy.mean(y) std = numpy.std(y) for i in range(len(y)): t_z.append((t[i]-mn)/std) dbp = [] for i in range(len(bp)-1): dbp.append(bp[i]-bp[i+1]) dwl = [] for i in range(len(z)-1): dwl.append(z[i]-z[i+1]) dt = [] for i in range(len(y)-1): dt.append(y[i]-y[i+1]) dbp.append(0) dwl.append(0) dt.append(0) ########################################################################### # ############################################################ Filter Signals # ########################################################################### ''' these filtered data are not necessary, but are good for graphical comparison ''' ### define filtering function def filt(frq,tol,data): #define frequency tolerance range lowcut = (frq-frq*tol) highcut = (frq+frq*tol) #conduct fft ffta = fft.fft(data) bp2 = ffta[:] fftb = fft.fftfreq(len(bp2)) #make every amplitude value 0 that is not in the tolerance range of frequency of interest #24 adjusts the frequency to cpd for i in range(len(fftb)): #spd is samples per day (if hourly = 24) if (fftb[i]*spd)>highcut or (fftb[i]*spd)<lowcut: bp2[i]=0 #conduct inverse fft to transpose the filtered frequencies back into time series crve = fft.ifft(bp2) yfilt = crve.real return yfilt #filter tidal data yfilt_O1 = filt(O1,tol,ydata) yfilt_M2 = filt(M2,tol,ydata) #filter wl data zfilt_O1 = filt(O1,tol,zdata) zfilt_M2 = filt(M2,tol,zdata) zffta = abs(fft.fft(zdata)) zfftb = abs(fft.fftfreq(len(zdata))*spd) def phasefind(A,frq): spectrum = fft.fft(A) freq = fft.fftfreq(len(spectrum)) r = [] #filter = eliminate all values in the wl data fft except the frequencies in the range of interest for i in range(len(freq)): #spd is samples per day (if hourly = 24) if (freq[i]*spd)>(frq-frq*tol) and (freq[i]*spd)<(frq+frq*tol): r.append(freq[i]*spd) else: r.append(0) #find the place of the max complex value for the filtered frequencies and return the complex number p = max(enumerate(r), key=itemgetter(1))[0] pla = spectrum[p] T5 = cmath.phase(pla)*180/pi return T5 yphsO1 = phasefind(ydata,O1) zphsO1 = phasefind(zdata,O1) phsO1 = zphsO1 - yphsO1 yphsM2 = phasefind(ydata,M2) zphsM2 = phasefind(zdata,M2) phsM2 = zphsM2 - yphsM2 # def phase_find(A,B,P): # period = P # tmax = len(xdata)*24 # nsamples = len(A) # # calculate cross correlation of the two signals # t6 = numpy.linspace(0.0, tmax, nsamples, endpoint=False) # xcorr = numpy.correlate(A, B) # # The peak of the cross-correlation gives the shift between the two signals # # The xcorr array goes from -nsamples to nsamples # dt6 = numpy.linspace(-t6[-1], t6[-1], 2*nsamples-1) # recovered_time_shift = dt6[xcorr.argmax()] # # # force the phase shift to be in [-pi:pi] # #recovered_phase_shift = 2*pi*(((0.5 + recovered_time_shift/(period*24)) % 1.0) - 0.5) # return recovered_time_shift # # # O1_ph= phase_find(ydata,zdata,P_O1) # M2_ph= phase_find(ydata,zdata,P_M2) ########################################################################### # ####################################################### Regression Analysis # ########################################################################### #define functions used for least squares fitting def f3(p, x): #a,b,c = p m = 2.0 * O1 * pi y = p[0] + p[1] * (numpy.cos(m*x)) + p[2] * (numpy.sin(m*x)) return y def f4(p, x): #a,b,c = p m =2.0 * M2 * pi y = p[0] + p[1] * (numpy.cos(m*x)) + p[2] * (numpy.sin(m*x)) return y #define functions to minimize def err3(p,y,x): return y - f3(p,x) def err4(p,y,x): return y - f4(p,x) #conducts regression, then calculates amplitude and phase angle def lstsq(func,y,x): #define starting values with x0 x0 = numpy.array([sum(y)/float(len(y)), 0.01, 0.01]) fit ,chks = optimization.leastsq(func, x0, args=(y, x)) amp = math.sqrt((fit[1]**2)+(fit[2]**2)) #amplitude phi = numpy.arctan(-1*(fit[2],fit[1]))*(180/pi) #phase angle return amp,phi,fit #water level signal regression WLO1 = lstsq(err3,zdata,xdata) WLM2 = lstsq(err4,zdata,xdata) #tide signal regression TdO1 = lstsq(err3,ydata,xdata) TdM2 = lstsq(err4,ydata,xdata) #calculate phase shift phase_sft_O1 = WLO1[1] - TdO1[1] phase_sft_M2 = WLM2[1] - TdM2[1] delt_O1 = (phase_sft_O1/(O1*360))*24 delt_M2 = (phase_sft_M2/(M2*360))*24 #determine tidal potential Cutillo and Bredehoeft 2010 pg 5 eq 4 f_O1 = math.sin(float(lat[1])*pi/180)*math.cos(float(lat[1])*pi/180) f_M2 = 0.5*math.cos(float(lat[1])*pi/180)**2 A2_M2 = g_ft*Km*b_M2*f_M2 A2_O1 = g_ft*Km*b_O1*f_O1 #Calculate ratio of head change to change in potential dW2_M2 = A2_M2/(WLM2[0]) dW2_O1 = A2_O1/(WLO1[0]) #estimate specific storage Cutillo and Bredehoeft 2010 def SS(rat): return 6.95690250E-10*rat Ss_M2 = SS(dW2_M2) Ss_O1 = SS(dW2_O1) def curv(Y,P,r): rc = (r/12.0)*(r/12.0) Y = Y X = -1421.15/(0.215746 + Y) - 13.3401 - 0.000000143487*Y**4 - 9.58311E-16*Y**8*math.cos(0.9895 + Y + 1421.08/(0.215746 + Y) + 0.000000143487*Y**4) T = (X*rc)/P return T Trans_M2 = curv(phase_sft_O1,P_M2,r) Trans_O1 = curv(phase_sft_M2,P_O1,r) ########################################################################### # ############################################ Calculate BP Response Function # ########################################################################### # create lag matrix for regression bpmat = tools.lagmat(dbp, lag, original='in') etmat = tools.lagmat(dt, lag, original='in') #lamat combines lag matrices of bp and et lamat = numpy.column_stack([bpmat,etmat]) #for i in range(len(etmat)): # lagmat.append(bpmat[i]+etmat[i]) #transpose matrix to determine required length #run least squared regression sqrd = numpy.linalg.lstsq(bpmat,dwl) #determine lag coefficients of the lag matrix lamat sqrdlag = numpy.linalg.lstsq(lamat,dwl) wlls = sqrd[0] #lagls return the coefficients of the least squares of lamat lagls = sqrdlag[0] cumls = numpy.cumsum(wlls) #returns cumulative coefficients of et and bp (lamat) lagcumls =numpy.cumsum(lagls) ymod = numpy.dot(bpmat,wlls) lagmod = numpy.dot(lamat,lagls) #resid gives the residual of the bp resid=[] for i in range(len(dwl)): resid.append(dwl[i] - ymod[i]) #alpha returns the lag coefficients associated with bp alpha = lagls[0:len(lagls)/2] alpha_cum = numpy.cumsum(alpha) #gamma returns the lag coefficients associated with ET gamma = lagls[len(lagls)/2:len(lagls)] gamma_cum = numpy.cumsum(gamma) lag_time = [] for i in range(len(xls_date)): lag_time.append((xls_date[i] - xls_date[0])*24) ######################################### determine slope of late time data lag_trim1 = lag_time[0:len(cumls)] lag_time_trim = lag_trim1[len(lag_trim1)-(len(lag_trim1)/2):len(lag_trim1)] alpha_trim = alpha_cum[len(lag_trim1)-(len(lag_trim1)/2):len(lag_trim1)] #calculate slope of late-time data lag_len = len(lag_time_trim) tran = numpy.array([lag_time_trim, numpy.ones(lag_len)]) reg_late = numpy.linalg.lstsq(tran.T,alpha_trim)[0] late_line=[] for i in range(len(lag_trim1)): late_line.append(reg_late[0] * lag_trim1[i] + reg_late[1]) #regression line ######################################## determine slope of early time data lag_time_trim2 = lag_trim1[0:len(lag_trim1)-int(round((len(lag_trim1)/1.5),0))] alpha_trim2 = alpha_cum[0:len(lag_trim1)-int(round((len(lag_trim1)/1.5),0))] lag_len1 = len(lag_time_trim2) tran2 = numpy.array([lag_time_trim2, numpy.ones(lag_len1)]) reg_early = numpy.linalg.lstsq(tran2.T,alpha_trim2)[0] early_line= [] for i in range(len(lag_trim1)): early_line.append(reg_early[0] * lag_trim1[i] + reg_early[1]) #regression line aquifer_type = [] if reg_early[0] > 0.001: aquifer_type = 'borehole storage' elif reg_early[0] < -0.001: aquifer_type = 'unconfined conditions' else: aquifer_type = 'confined conditions' ########################################################################### # ################################################################ Make Plots # ########################################################################### fig_1_lab = well_name + ' bp response function' fig_2_lab = well_name + ' signal processing' plt.figure(fig_1_lab) plt.suptitle(fig_1_lab, x= 0.2, y=.99, fontsize='small') plt.subplot(2,1,1) #plt.plot(lag_time[0:len(cumls)],cumls, label='b.p. alone') plt.plot(lag_time[0:len(cumls)],alpha_cum,"o", label='b.p. when \n considering e.t.') # plt.plot(lag_time[0:len(cumls)],gamma_cum, label='e.t.') plt.plot(lag_trim1, late_line, 'r-', label='late reg.') plt.plot(lag_trim1, early_line, 'g-', label='early reg.') plt.xlabel('lag (hr)') plt.ylabel('cumulative response function') plt.legend(loc=4,fontsize='small') plt.subplot(2,1,2) plt.plot(lag_time,dwl, label='wl', lw=2) plt.plot(lag_time,ymod, label='wl modeled w bp') plt.plot(lag_time,lagmod, 'r--', label='wl modeled w bp&et') plt.legend(loc=4,fontsize='small') plt.xlim(0,lag) plt.ylabel('change (ft)') plt.xlabel('time (hrs)') plt.tight_layout() plt.savefig('l'+ os.path.splitext(impfile)[0]+'.pdf') plt.figure(fig_2_lab) plt.suptitle(fig_2_lab, x=0.2, fontsize='small') plt.title(os.path.splitext(impfile)[0]) plt.subplot(4,1,1) plt.xcorr(yfilt_O1,zfilt_O1,maxlags=10) plt.ylim(-1.1,1.1) plt.tick_params(labelsize=8) plt.xlabel('lag (hrs)',fontsize='small') plt.ylabel('lag (hrs)',fontsize='small') plt.title('Cross Correl O1',fontsize='small') plt.subplot(4,1,2) plt.xcorr(yfilt_M2,zfilt_M2,maxlags=10) plt.ylim(-1.1,1.1) plt.tick_params(labelsize=8) plt.xlabel('lag (hrs)',fontsize='small') plt.ylabel('lag (hrs)',fontsize='small') plt.title('Cross Correl M2',fontsize='small') plt.subplot(4,1,3) plt.plot(zfftb,zffta) plt.tick_params(labelsize=8) plt.xlabel('frequency (cpd)',fontsize='small') plt.ylabel('amplitude') plt.title('WL fft',fontsize='small') plt.xlim(0,4) plt.ylim(0,30) plt.subplot(4,1,4) plt.plot(x0data,zdata, 'b') plt.tick_params(labelsize=8) plt.xlabel('julian days',fontsize='small') plt.ylabel('water level (ft)',fontsize='small') plt.twinx() plt.plot(x0data,f3(WLO1[2],x0data), 'r') plt.plot(x0data,f4(WLM2[2],x0data), 'g') plt.tick_params(labelsize=8) plt.xlim(0,10) plt.ylabel('tidal strain (ppb)',fontsize='small') plt.tick_params(labelsize=8) plt.tight_layout() plt.title('Regression Fit',fontsize='small') plt.savefig('f'+ os.path.splitext(impfile)[0]+'.pdf') plt.close() ########################################################################### #Write output to files ########################################################################### # create row of data for compiled output file info.csv myCSVrow = [os.path.splitext(inpfile)[0],well_name, A2_O1, A2_M2, phase_sft_O1, phase_sft_M2, delt_O1, delt_M2, Trans_M2, Trans_O1, Ss_O1, Ss_M2, WLO1[1], TdO1[1], WLM2[1], TdM2[1], WLO1[0], TdO1[0], WLM2[0], TdM2[0], WLO1[2][1], TdO1[2][1], WLM2[2][1], TdM2[2][1], WLO1[2][2], TdO1[2][2], WLM2[2][2], TdM2[2][2], reg_late[1], reg_early[0], aquifer_type, phsO1, phsM2] # add data row to compiled output file compfile = open('info.csv', 'a') writer = csv.writer(compfile) writer.writerow(myCSVrow) compfile.close() #export tidal data to individual (well specific) output file with open(outfile, "wb") as f: filewriter = csv.writer(f, delimiter=',') #write header header = ['xl_time','date_time','V_ugal','vert_mm','areal_mm','WDD_tam','potential','dilation_ppb','wl_ft','dbp','dwl','resid','bp','Tsoft_SG23'] filewriter.writerow(header) for row in range(0,1): for i in range(len(d)): #you can add more columns here filewriter.writerow([xls_date[i],d[i],Grav_tide[i],vert[i],areal[i],WDD_tam[i],potential[i], dilation[i],wl[i],dbp[i],dwl[i],resid[i],bp[i],etint[i]])