GAMMOD Procedure

specifies a global significance level for the hypothesis testing of smoothing components and the construction of Bayesian confidence bands of predictions. The confidence level is 1 – number. The value of number must be between 0 and 1; the default is 0.05. You can override this global significance level for Bayesian confidence bands of predictions by specifying the ALPHA= option in the OUTPUT statement.

names the input data table for PROC GAMMOD to use. The default is the most recently created data table. libref.data-table is a two-level name, where

adds to the "Iteration History" table the current values of the parameter estimates and their gradients. If the optimization algorithm is used to determine at least one smoothing parameter, the table lists values for smoothing parameters. If all smoothing parameters are fixed or a parametric generalized linear model is specified, the table lists values for regression parameters. These quantities are reported only for parameters that participate in the optimization.

suppresses the display of the "Class Level Information" table if you do not specify number. If you specify number, the values of the classification variables are displayed for only those variables whose number of levels is less than number. Specifying a number helps reduce the size of the "Class Level Information" table if some classification variables have a large number of levels.

suppresses the generation of ODS output.

specifies optimization parameters for either maximum or penalized likelihood estimation. For more information about which optimization-parameters you can specify, see the section Optimization Parameters. For the performance iteration method, only the ABSFCONV=, FCONV=, and MAXITER= options are effective for determining when the performance iteration should have converged. If the distribution family involves a dispersion parameter that needs to be estimated by the maximum likelihood method, all the optimization parameters in this option are applicable.

controls the plots that are produced through ODS Graphics. When ODS Graphics is enabled, PROC GAMMOD produces by default a panel of plots of partial prediction curves or surfaces of smoothing components.

ods graphics on;

proc gammod plots;
   model y=spline(x1) spline(x2);
run;

ods graphics off;

You can specify the following global-plot-option, which applies to the smoothing component plots that the GAMMOD procedure generates:

You can specify the following plot-requests:

specifies an integer that is used to start the pseudorandom number generator for truncated eigendecomposition and for subset sampling from observations to form knots if necessary. If you do not specify this option or if number 0, the seed is generated from the time of day, which is read from the computer’s clock.

tunes the singularity criterion in Cholesky decomposition and matrix inversion operations. The default is 1E4 times the machine epsilon; this product is approximately 1E–12 on most computers.

tunes the singularity criterion in truncated eigendecomposition to determine its convergence. The default is 1E4 times the machine epsilon; this product is approximately 1E–12 on most computers.

specifies optimization parameters for smoothing parameter estimation. For more information about which optimization-parameters you can specify, see the next section. For parametric generalized linear models or generalized additive models that have fixed smoothing parameters, any optimization parameters that you specify for this option are ignored.