The PANEL Procedure

MODEL Statement

MODEL response = regressors </ options> ;

The MODEL statement specifies the regression model and the error structure assumed for the regression residuals. The response variable on the left side of the equal sign is regressed on the independent variables listed after the equal sign. Any number of MODEL statements can be used. For each model statement, only one response variable can be specified on the left side of the equal sign.

The error structure is specified by the FULLER, PARKS, DASILVA, FIXONE, FIXONETIME, FIXTWO, RANONE, RANTWO, GMM, and ITGMM options. More than one of these options can be used, in which case the analysis is repeated for each error structure model specified.

Models can be given labels. Model labels are used in the printed output to identify the results for different models. If no label is specified, the response variable name is used as the label for the model. The model label is specified as follows:

label : MODEL ...;

The following options can be specified in the MODEL statement after a slash (/).

ARTEST=integer: specifies the maximum order of the test for the presence of AR effects in the residual in the dynamic panel model. The acceptable range of values for this option is 1 to $\text{[math]}$ .
ATOL=number: specifies the convergence criterion for iterated GMM when convergence of the method is determined by convergence in the weighting matrix. The convergence criterion must be positive. The default option is the BTOL= option unless the ATOL= option is specified. See the section Dynamic Panel Estimator for details.
BANDOPT=TRAILING | CENTERED | LEADING: specifies which observations are included in the instrument list when the MAXBAND= option is specified. This option should be used only for exogenous instruments. BANDOPT=TRAILING is the default. See the section Dynamic Panel Estimator for details.
BP: requests the Breusch-Pagan one-way test for random effects.
BP2: requests the Breusch-Pagan two-way test for random effects.
BTOL=number: specifies the convergence criterion for iterated GMM when convergence of the method is determined by convergence in the parameter matrix. The convergence criterion must be positive. The default is BTOL=1E–8. See the section Dynamic Panel Estimator for details.
BTWNG: specifies that a between-groups model be estimated.
BTWNT: specifies that a between-time-periods model be estimated.
CLUSTER: specifies the cluster correction for the variance-covariance matrix. The cluster correction can be requested with HCCME=0, 1, 2 or 3.
CORRB
CORR: prints the matrix of estimated correlations between the parameter estimates.
COVB
VAR: prints the matrix of estimated covariances between the parameter estimates.
DASILVA: specifies that the model be estimated by using the Da Silva method, which assumes a mixed variance-component moving average model for the error structure. See the section Da Silva Method (Variance-Component Moving Average Model) for details.
FIXONE: specifies that a one-way fixed-effects model be estimated with the one-way model corresponding to cross-sectional effects only.
FIXONETIME: specifies that a one-way fixed-effects model be estimated with the one-way model corresponding to time effects only.
FIXTWO: specifies that a two-way fixed-effects model be estimated.
GINV= G2 | G4: specifies what type of generalized inverse to use. The default is a G2 inverse. The G4 inverse is generally more desirable except that it is a more numerically intensive methodology.
GMM: specifies that the model be estimated by using the dynamic panel estimator method, which allows for autoregressive processes. This is the single-step model. Note that with this option one INSTRUMENT statement is required for each MODEL statement. See the section Dynamic Panel Estimator for details.
HCCME=number: specifies the type of HCCME variance-covariance matrix requested. The expected range of values is NO or 0 to 4. The default is NO, no correction. See the section Heteroscedasticity-Corrected Covariance Matrices for details.
ITGMM: specifies that the model be estimated by using the dynamic panel estimator method, but that PROC PANEL keep updating the weighting matrix until either the parameter vector converges or the weighting matrix converges. See the section Dynamic Panel Estimator for details.
ITPRINT: prints out the iteration history of the parameter and transformed sum of error squared.
M=number: specifies the order of the moving-average process in the Da Silva method. The value of the M=option must be less than $\text{[math]}$ . The default is M=1.
MAXBAND=integer: specifies the maximum number of time periods (per instrumental variable) that are allowed into the moment condition. The acceptable range of values for this option is 1 to $\text{[math]}$ . If BANDOPT=LEADING or CENTERED, then the default value of MAXBAND is 2. If BANDOPT=TRAILING, then the default value of MAXBAND is 1. If no BANDOPT option is specified such as when no exogenous instruments are used, then the default value of MAXBAND is 1. See the section Dynamic Panel Estimator for details.
MAXITER=integer: specifies the maximum number of iterations allowed for the iterated GMM option. The default value is MAXITER=200. See the section Dynamic Panel Estimator for details.
NODIFFS: specifies that the dynamic panel model be estimated without moment conditions from the difference equations. See the section Dynamic Panel Estimator for details.
NOESTIM: limits the estimation of a FIXONE, FIXONETIME, RANONE model to the generation of the transformed series. This option is intended for use with an OUTTRANS= data set.
NOINT: suppresses the intercept parameter from the model.
NOLEVELS: specifies that the dynamic panel model be estimated without moment conditions from the level equations. See the section Dynamic Panel Estimator for details.
NOPRINT: suppresses the normal printed output.
PARKS: specifies that the model be estimated by using the Parks method, which assumes a first-order autoregressive model for the error structure. See the section Parks Method (Autoregressive Model) for details.
PHI: prints the $\text{[math]}$ matrix of estimated covariances of the observations for the Parks method. The PHI option is relevant only when the PARKS option is used. See the section Parks Method (Autoregressive Model) for details.
POOLED: specifies that a pooled (OLS) model be estimated.
RANONE: specifies that a one-way random-effects model be estimated.
RANTWO: specifies that a two-way random-effects model be estimated.
RHO: prints the estimated autocorrelation coefficients for the Parks method.
ROBUST: specifies that the robust weighting matrix be used in the calculation of the variance-covariance matrix of the single-step dynamic panel estimator. See the section Dynamic Panel Estimator for details.
SINGULAR=number: specifies a singularity criterion for the inversion of the matrix. The default depends on the precision of the computer system.
TIME: specifies that the model be estimated by using the dynamic panel estimator method, but that PROC PANEL includes time dummy variables to model any time effects present in the data. See the section Dynamic Panel Estimator for details.
TWOSTEP: specifies that the model be estimated by using the dynamic panel estimator method, but that two steps be used in the estimation. An initial first step is used to form an estimator for the weighting matrix used in the second step. See the section Dynamic Panel Estimator for details.
VCOMP=FB | NL | WH | WK: specifies the type of variance component estimate to use. The default is VCOMP=FB for balanced data and VCOMP=WK for unbalanced data. See the section The One-Way Random-Effects Model and The Two-Way Random-Effects Model for details.