spreg.ML_Lag_Regimes¶
- class spreg.ML_Lag_Regimes(y, x, regimes, w=None, constant_regi='many', cols2regi='all', method='full', epsilon=1e-07, slx_lags=0, regime_lag_sep=False, cores=False, spat_diag=True, spat_impacts='simple', vm=False, name_y=None, name_x=None, name_w=None, name_ds=None, name_regimes=None, latex=False)[source]¶
ML estimation of the spatial lag model with regimes (note no consistency checks, diagnostics or constants added) [Ans88].
- Parameters:
- y
numpy.ndarray
orpandas.Series
nx1 array for dependent variable
- x
numpy.ndarray
orpandas
object
Two dimensional array with n rows and one column for each independent (exogenous) variable, excluding the constant
- regimes
list
orpandas.Series
List of n values with the mapping of each observation to a regime. Assumed to be aligned with ‘x’.
- constant_regi: string
Switcher controlling the constant term setup. It may take the following values:
‘one’: a vector of ones is appended to x and held constant across regimes
‘many’: a vector of ones is appended to x and considered different per regime (default)
- cols2regi
list
, ‘all’ Argument indicating whether each column of x should be considered as different per regime or held constant across regimes (False). If a list, k booleans indicating for each variable the option (True if one per regime, False to be held constant). If ‘all’ (default), all the variables vary by regime.
- w
Sparse
matrix
Spatial weights sparse matrix
- method
str
if ‘full’, brute force calculation (full matrix expressions) if ‘ord’, Ord eigenvalue method if ‘LU’, LU sparse matrix decomposition
- epsilon
float
tolerance criterion in mimimize_scalar function and inverse_product
- slx_lags
integer
Number of spatial lags of X to include in the model specification. If slx_lags>0, the specification becomes of the Spatial Durbin type.
- regime_lag_sep: boolean
If True, the spatial parameter for spatial lag is also computed according to different regimes. If False (default), the spatial parameter is fixed accross regimes.
- spat_diagbool
If True, then compute Common Factor Hypothesis test when applicable
- spat_impacts
str
orlist
- Include average direct impact (ADI), average indirect impact (AII),
and average total impact (ATI) in summary results. Options are ‘simple’, ‘full’, ‘power’, ‘all’ or None. See sputils.spmultiplier for more information.
- coresbool
Specifies if multiprocessing is to be used Default: no multiprocessing, cores = False Note: Multiprocessing may not work on all platforms.
- vmbool
if True, include variance-covariance matrix in summary results
- name_y
str
Name of dependent variable for use in output
- name_x
list
of
strings
Names of independent variables for use in output
- name_w
str
Name of weights matrix for use in output
- name_ds
str
Name of dataset for use in output
- name_regimes
str
Name of regimes variable for use in output
- latexbool
Specifies if summary is to be printed in latex format
- y
- Attributes:
- output
dataframe
regression results pandas dataframe
- summary
str
Summary of regression results and diagnostics (note: use in conjunction with the print command)
- betas
array
(k+1)x1 array of estimated coefficients (rho first)
- rho
float
estimate of spatial autoregressive coefficient Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- u
array
nx1 array of residuals
- predy
array
nx1 array of predicted y values
- n
integer
Number of observations
- k
integer
Number of variables for which coefficients are estimated (including the constant, excluding the rho) Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- y
array
nx1 array for dependent variable
- x
array
Two dimensional array with n rows and one column for each independent (exogenous) variable, including the constant Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- method
str
log Jacobian method. if ‘full’: brute force (full matrix computations) if ‘ord’, Ord eigenvalue method if ‘LU’, LU sparse matrix decomposition
- cfh_test
tuple
Common Factor Hypothesis test; tuple contains the pair (statistic, p-value). Only when it applies (see specific documentation).
- epsilon
float
tolerance criterion used in minimize_scalar function and inverse_product
- mean_y
float
Mean of dependent variable
- std_y
float
Standard deviation of dependent variable
- vm
array
Variance covariance matrix (k+1 x k+1), all coefficients
- vm1
array
Variance covariance matrix (k+2 x k+2), includes sig2 Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- sig2
float
Sigma squared used in computations Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- logll
float
maximized log-likelihood (including constant terms) Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- aic
float
Akaike information criterion Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- schwarz
float
Schwarz criterion Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- predy_e
array
predicted values from reduced form
- e_pred
array
prediction errors using reduced form predicted values
- pr2
float
Pseudo R squared (squared correlation between y and ypred) Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- pr2_e
float
Pseudo R squared (squared correlation between y and ypred_e (using reduced form)) Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- std_err
array
1xk array of standard errors of the betas Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- z_stat
list
of
tuples
z statistic; each tuple contains the pair (statistic, p-value), where each is a float Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- sp_multipliers: dict
Dictionary of spatial multipliers (if spat_impacts is not None) Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- name_y
str
Name of dependent variable for use in output
- name_x
list
of
strings
Names of independent variables for use in output
- name_w
str
Name of weights matrix for use in output
- name_ds
str
Name of dataset for use in output
- name_regimes
str
Name of regimes variable for use in output
- title
str
Name of the regression method used Only available in dictionary ‘multi’ when multiple regressions (see ‘multi’ below for details)
- regimes
list
List of n values with the mapping of each observation to a regime. Assumed to be aligned with ‘x’.
- constant_regi: [‘one’, ‘many’]
Ignored if regimes=False. Constant option for regimes. Switcher controlling the constant term setup. It may take the following values:
‘one’: a vector of ones is appended to x and held constant across regimes
‘many’: a vector of ones is appended to x and considered different per regime
- cols2regi
list
, ‘all’ Ignored if regimes=False. Argument indicating whether each column of x should be considered as different per regime or held constant across regimes (False). If a list, k booleans indicating for each variable the option (True if one per regime, False to be held constant). If ‘all’, all the variables vary by regime.
- regime_lag_sep: boolean
If True, the spatial parameter for spatial lag is also computed according to different regimes. If False (default), the spatial parameter is fixed accross regimes.
- regime_err_sep: boolean
always set to False - kept for compatibility with other regime models
- kr
int
Number of variables/columns to be “regimized” or subject to change by regime. These will result in one parameter estimate by regime for each variable (i.e. nr parameters per variable)
- kf
int
Number of variables/columns to be considered fixed or global across regimes and hence only obtain one parameter estimate
- nr
int
Number of different regimes in the ‘regimes’ list
- multi
dictionary
Only available when multiple regressions are estimated, i.e. when regime_err_sep=True and no variable is fixed across regimes. Contains all attributes of each individual regression
- output
Examples
Open data baltim.dbf using pysal and create the variables matrices and weights matrix.
>>> import numpy as np >>> import libpysal >>> from libpysal import examples >>> from libpysal.examples import load_example >>> from libpysal.weights import Queen >>> from spreg import ML_Lag_Regimes >>> import geopandas as gpd >>> np.set_printoptions(suppress=True) #prevent scientific format >>> baltimore = load_example('Baltimore') >>> db = libpysal.io.open(baltimore.get_path("baltim.dbf"),'r') >>> df = gpd.read_file(baltimore.get_path("baltim.shp")) >>> ds_name = "baltim.dbf" >>> y_name = "PRICE" >>> y = np.array(db.by_col(y_name)).T >>> y.shape = (len(y),1) >>> x_names = ["NROOM","AGE","SQFT"] >>> x = np.array([db.by_col(var) for var in x_names]).T >>> w = Queen.from_dataframe(df) >>> w_name = "baltim_q.gal" >>> w.transform = 'r'
Since in this example we are interested in checking whether the results vary by regimes, we use CITCOU to define whether the location is in the city or outside the city (in the county):
>>> regimes = db.by_col("CITCOU")
Now we can run the regression with all parameters:
>>> mllag = ML_Lag_Regimes(y,x,regimes,w=w,name_y=y_name,name_x=x_names, name_w=w_name,name_ds=ds_name,name_regimes="CITCOU") >>> np.around(mllag.betas, decimals=4) array([[-14.5158], [ 4.4923], [ -0.0336], [ 0.3541], [ -3.601 ], [ 3.8736], [ -0.1747], [ 0.8238], [ 0.525 ]]) >>> "{0:.6f}".format(mllag.rho) '0.524971' >>> "{0:.6f}".format(mllag.mean_y) '44.307180' >>> "{0:.6f}".format(mllag.std_y) '23.606077' >>> np.around(np.diag(mllag.vm1), decimals=4) array([ 48.6818, 2.4524, 0.0052, 0.0663, 71.4439, 3.2837, 0.0118, 0.0498, 0.0042, 409.1225]) >>> np.around(np.diag(mllag.vm), decimals=4) array([48.6818, 2.4524, 0.0052, 0.0663, 71.4439, 3.2837, 0.0118, 0.0498, 0.0042]) >>> "{0:.6f}".format(mllag.sig2) '204.827093' >>> "{0:.6f}".format(mllag.logll) '-867.086467' >>> "{0:.6f}".format(mllag.aic) '1752.172934' >>> "{0:.6f}".format(mllag.schwarz) '1782.339657' >>> mllag.title 'MAXIMUM LIKELIHOOD SPATIAL LAG - REGIMES (METHOD = full)'
- __init__(y, x, regimes, w=None, constant_regi='many', cols2regi='all', method='full', epsilon=1e-07, slx_lags=0, regime_lag_sep=False, cores=False, spat_diag=True, spat_impacts='simple', vm=False, name_y=None, name_x=None, name_w=None, name_ds=None, name_regimes=None, latex=False)[source]¶
Methods
ML_Lag_Regimes_Multi
(y, x, w_i, w, regi_ids, ...)__init__
(y, x, regimes[, w, constant_regi, ...])Attributes
- ML_Lag_Regimes_Multi(y, x, w_i, w, regi_ids, slx_lags, cores, cols2regi, method, epsilon, spat_diag, spat_impacts, vm, name_y, name_x, name_regimes, name_w, name_ds, latex)[source]¶
- property mean_y¶
- property sig2n¶
- property sig2n_k¶
- property std_y¶
- property utu¶
- property vm¶