The ENTROPY Procedure |
PROC ENTROPY Statement |
The following options can be specified in the PROC ENTROPY statement.
requests that the collinearity diagnostics of the matrix be printed.
specifies the method for producing the covariance matrix of parameters for output and for standard error calculations. GMENM and GME are aliases and are the default.
requests generalized maximum entropy or generalized cross entropy. This is the default estimation method.
requests normed moment maximum entropy or the normed moment cross entropy.
requests a variant of GME suitable for multinomial discrete choice models.
specifies seemingly unrelated regression or iterated seemingly unrelated regression.
specifies the denominator to be used in computing variances and covariances. VARDEF=N specifies that the number of nonmissing observations be used. VARDEF=WGT specifies that the sum of the weights be used. VARDEF=DF specifies that the number of nonmissing observations minus the model degrees of freedom (number of parameters) be used. VARDEF=WDF specifies that the sum of the weights minus the model degrees of freedom be used. The default is VARDEF=DF.
specifies the input data set. Values for the variables in the model are read from this data set.
names the SAS data set that contains the data about priors and supports.
names the SAS data set to contain the residuals from each estimation.
writes the covariance matrix of the estimates to the OUTEST= data set in addition to the parameter estimates. The OUTCOV option is applicable only if the OUTEST= option is also specified.
names the SAS data set to contain the parameter estimates and optionally the covariance of the estimates.
names the SAS data set to contain the estimated Lagrange multipliers for the models.
names the SAS data set to contain the support points and estimated probabilities.
names the SAS data set to contain the estimated covariance matrix of the equation errors. This is the covariance of the residuals computed from the parameter estimates.
names the SAS data set to contain the matrix used in the objective function definition. The OUTSUSED= data set is the same as the OUTS= data set for the methods that iterate the matrix.
specifies a data set that provides the covariance matrix of the equation errors. The matrix read from the SDATA= data set is used for the equation error covariance matrix ( matrix) in the estimation. The SDATA= matrix is used to provide only the initial estimate of for the methods that iterate the S matrix.
prints the parameter estimates, objective function value, and convergence criteria at each iteration.
suppresses the normal printed output but does not suppress error listings. Using any other print option turns the NOPRINT option off.
requests that the ENTROPY procedure produce statistical graphics via the Output Delivery System, provided that the ODS GRAPHICS statement has been specified. For general information about ODS Graphics, see Chapter 21, Statistical Graphics Using ODS (SAS/STAT User's Guide). The global-plot-options apply to all relevant plots generated by the ENTROPY procedure.
The global-plot-options supported by the ENTROPY procedure are as follows:
suppresses the default plots. Only the plots specifically requested are produced.
breaks a graphic that is otherwise paneled into individual component plots.
The specific plot-request values supported by the ENTROPY procedure are as follows:
requests that all plots appropriate for the particular analysis be produced. ALL is equivalent to specifying FITPLOT, COOKSD, QQ, RESIDUALHISTOGRAM, and STUDENTRESIDUAL.
plots the predicted and actual values.
produces the Cook’s D plot.
produces a Q-Q plot of residuals.
plots the histogram of residuals.
plots the studentized residuals.
suppresses all plots.
When ODS graphics are enabled, the default behavior is to plot all plots appropriate for the particular analysis (ALL) in a panel.
The following options can be helpful if a convergence problem occurs for a given model and set of data. The ENTROPY procedure uses the nonlinear optimization subsystem (NLO) to perform the model optimizations. In addition to the options listed below, all options supported in the NLO subsystem can be specified on the ENTROPY procedure statement. See Chapter 6, Nonlinear Optimization Methods, for more details.
specifies the convergence criteria for S-iterated methods. The convergence measure computed during model estimation must be less than value before convergence is assumed. The default value is CONVERGE=0.001.
specifies whether the optimization problem is solved using the dual or primal form. The dual form is the default.
specifies the maximum number of iterations allowed. The default is MAXITER=100.
specifies the maximum number of subiterations allowed for an iteration. The MAXSUBITER= option limits the number of step halvings. The default is MAXSUBITER=30.
specifies the iterative minimization method to use. METHOD=TR specifies the trust region method, METHOD=NEWRAP specifies the Newton-Raphson method, METHOD=NRR specifies the Newton-Raphson ridge method, and METHOD=QN specifies the quasi-Newton method. See Chapter 6, Nonlinear Optimization Methods, for more details about optimization methods. The default is METHOD=QN for the dual form and METHOD=NEWRAP for the primal form.
Note: This procedure is experimental.
Copyright © 2008 by SAS Institute Inc., Cary, NC, USA. All rights reserved.