spreg.PanelRE¶
- class spreg.PanelRE(y, x, w, slx_lags=0, slx_vars='all', time_effects=False, spat_diag=True, vm=False, name_y=None, name_x=None, name_w=None, name_ds=None, latex=False)[source]¶
Random Effects (One-Way or Two-Way) GLS for Panel Data.
Includes the Swamy-Arora estimator for variance components and the classic Hausman Specification Test (not robust to spatial autocorrelation).
- Parameters:
- y
numpy.ndarrayorpandasobject nxt or (nxt)x1 array for dependent variable
- x
numpy.ndarrayorpandasobject nx(txk) or (nxt)xk array for independent (exogenous) variables.
- w
pysalWobject Spatial weights object. Required to determine cross-sectional dimension (N).
- slx_lags
integer Number of spatial lags of X to include in the model specification. If slx_lags>0, the specification becomes of the SLX type.
- slx_vars
either“All” (default)orlistofbooleanstoselectxvariables to be lagged
- time_effectsbool
If True, then include time dummies in the model specification (first omitted). Default: False
- spat_diagbool
If True (default), then compute the ‘LMC_spatial’ BSK test.
- vmbool
if True, include variance-covariance matrix in summary results
- name_y
str Name of dependent variable for use in output
- name_x
listofstrings 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
- 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 kx1 array of estimated coefficients
- u
array (nxt)x1 array of residuals
- predy
array (nxt)x1 array of predicted y values
- n
integer Total number of observations (N * T)
- t
integer Number of time periods
- k
integer Number of variables
- theta
float The quasi-demeaning weight (0 = Pooled, 1 = FE)
- hausman_stat
float Chi-square statistic for the Hausman test
- hausman_p
float P-value for the Hausman test
- sigma2_mu
float Estimated variance of the random effects
- sigma2_epsilon
float Estimated variance of the idiosyncratic errors
- output
Examples
>>> import libpysal >>> import geopandas as gpd >>> from spreg import PanelRE
In this example, we will use data on NCOVR US County Homicides (3085 areas) included in libpysal.
>>> libpysal.examples.load_example('NCOVR') >>> db = gpd.read_file(libpysal.examples.get_path("NAT.shp")) >>> name_ds = "NCOVR.shp"
Extract the HR (homicide rates) data in the 70’s, 80’s and 90’s from the dataframe and make it the dependent variable for the regression. Note that the data can also be passed in the long format instead of wide format (i.e. a vector with n*t rows and a single column for the dependent variable and a matrix of dimension n*txk for the independent variables).
>>> y_name = ['HR70','HR80','HR90'] >>> y = db[y_name]
Extract RD and PS in the same time periods from the dataframe to be used as independent variables in the regression. IMPORTANT: The data must be organized in a way that all time periods of a given variable are side-by-side and in the correct time order. That is: x[:, 0:T] refers to T periods of k1, x[:, T+1:2T] refers to k2, etc. By default a vector of ones will be added to the independent variables passed in.
>>> x_names = ['RD70','RD80','RD90','PS70','PS80','PS90'] >>> x = db[x_names]
Even if we are not running a spatial model, we need to specify the spatial weights matrix that includes the spatial configuration of the observations for the diagnostics. To do that, we can open an already existing gal file or create a new one. In this case, we will create one from
NAT.shp.>>> w = libpysal.weights.Queen.from_dataframe(db, use_index=True) >>> w.transform = 'r' >>> name_w = "NCOVR.gal"
We are all set with the preliminaries, we are good to run the model.
>>> reg = PanelRE(y, x, w)
Once we have run the model, we can explore a little bit the output with the command print(reg.summary).
- __init__(y, x, w, slx_lags=0, slx_vars='all', time_effects=False, spat_diag=True, vm=False, name_y=None, name_x=None, name_w=None, name_ds=None, latex=False)[source]¶
Methods
__init__(y, x, w[, slx_lags, slx_vars, ...])Attributes
- property mean_y¶
- property sig2n¶
- property sig2n_k¶
- property std_y¶
- property utu¶
- property vm¶