MODEL Statement 
A MODEL statement signifies the beginning of a model specification block and designates a model number for the model. All main and subsidiary model specification statements after a MODEL statement belong in that model until another MODEL or GROUP statement is encountered.
The MODEL statement itself does not serve the purpose of model specification, which is actually done by the main and subsidiary model specification statements that follow it. The MODEL statement serves as a "placeholder" of specification of a single model. It also makes the reference to a model easier with an assigned model number. For example, consider the following statements:
proc calis; group 1 / data=women_data; group 2 / data=men_data; model 1 / group=1 label='Women Model'; {model 1 specification here} model 2 / group=2 label='Men Model'; {model 2 specification here} run;
This example illustrates a twogroup analysis with two models. One is model 1 labeled as 'Women Model' in a MODEL statement. Another is model 2 labeled as 'Men Model' in another MODEL statement. The two groups, group 1 and group 2, as defined in two separate GROUP statements, are fitted by model 1 and model 2, respectively, as indicated by the GROUP= option of the MODEL statements. Within the scope of model 1, you provide model specification statements by using the main and subsidiary model specification statements. Usually, one of the following main model specification statements is used: FACTOR, LINEQS, LISMOD, MSTRUCT, PATH, RAM, or REFMODEL. Similarly, you provide another set of model specification statements within the scope of model 2.
Hence, for an analysis with a single group, the use of the MODEL statement is not necessary because the model that fits the group is unambiguous.
You can set modelspecific options in each MODEL statement. All but two of these options are also available in the PROC CALIS statement. If you set these options in the PROC CALIS statement, they apply to all models, unless you respecify them in the local MODEL statements. If you want to apply some options only to a particular model, specify these options in the MODEL statement that corresponds to that model.
You can also set groupspecific options in the MODEL statement. These group options apply to the groups that are specified in GROUP= option of the MODEL statement. See the section Options Available in the GROUP and PROC CALIS Statements for a detailed descriptions of these group options.
The following options are available in the MODEL and PROC CALIS statements. If you specify these options in the PROC CALIS statement, they are transferred to all MODEL statements. These options might be overwritten by the respecifications in the local MODEL statements.
Option 
Description 

Emphasizes the diagonal entries 

Displays total, direct, and indirect effects 

Displays the extended path estimates that include variances and covariances 

Specifies the data set that contains the initial values and constraints 

Specifies the data set that contains the model specifications 

Analyzes the mean structures 

Computes modification indices 

Deactivates the inherited MEANSTR option 

Suppresses modification indices 

Displays model specifications and results according to the input order 

Suppresses the printing of parameter names in results 

Suppresses the standardized output 

Suppresses standard error computations 

Orders the model output displays according to the parameter types within each model 

Specifies the data set that outputs the estimates and their covariance matrix 

Specifies the output data set for storing the model specification and results 

Displays parameter names in model specifications and results 

Computes the determination coefficients 

Prints parameter estimates 

Prints initial pattern and values 

Computes the latent variable covariances and scoring coefficients 

Displays results in matrix forms 

Instructs generated default parameters be read in the INMODEL= data set 

Computes the standard errors 
Some options in the GROUP statement can also be specified in the MODEL statements. Group options that are specified the MODEL statements are transferred to the GROUP statements that define the groups that are fitted by the associated models in the MODEL statements. This is a little more convenient than setting the common group options individually in the GROUP statements for all fitted groups by a model. See the section Options Available in GROUP, MODEL, and PROC CALIS Statements for a reference of these options.