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| The CALIS Procedure |
| Data Set Options | Short Description |
| DATA= | input data set |
| INEST= | input initial values, constraints |
| INRAM= | input model |
| INWGT= | input weight matrix |
| OUTEST= | covariance matrix of estimates |
| OUTJAC | Jacobian into OUTEST= data set |
| OUTRAM= | output model |
| OUTSTAT= | output statistic |
| OUTWGT= | output weight matrix |
| Data Processing | Short Description |
| AUGMENT | analyzes augmented moment matrix |
| COVARIANCE | analyzes covariance matrix |
| EDF= | defines nobs by number error df |
| NOBS= | defines number of observations nobs |
| NOINT | analyzes uncorrected moments |
| RDF= | defines nobs by number regression df |
| RIDGE | specifies ridge factor for moment matrix |
| UCORR | analyzes uncorrected CORR matrix |
| UCOV | analyzes uncorrected COV matrix |
| VARDEF= | specifies variance divisor |
| Estimation Methods | Short Description |
| METHOD= | estimation method |
| ASYCOV= | formula of asymptotic covariances |
| DFREDUCE= | reduces degrees of freedom |
| G4= | algorithm for STDERR |
| NODIAG | excludes diagonal elements from fit |
| WPENALTY= | penalty weight to fit correlations |
| WRIDGE= | ridge factor for weight matrix |
| Optimization Techniques | Short Description |
| TECHNIQUE= | minimization method |
| UPDATE= | update technique |
| LINESEARCH= | line-search method |
| FCONV= | function convergence criterion |
| GCONV= | gradient convergence criterion |
| INSTEP= | initial step length (RADIUS=, SALPHA=) |
| LSPRECISION= | line-search precision (SPRECISION=) |
| MAXFUNC= | max number function calls |
| MAXITER= | max number iterations |
| Displayed Output Options | Short Description |
| KURTOSIS | compute and display kurtosis |
| MODIFICATION | modification indices |
| NOMOD | no modification indices |
| NOPRINT | suppresses the displayed output |
| PALL | all displayed output (ALL) |
| PCORR | analyzed and estimated moment matrix |
| PCOVES | covariance matrix of estimates |
| PDETERM | determination coefficients |
| PESTIM | parameter estimates |
| PINITIAL | pattern and initial values |
| PJACPAT | displays structure of variable and constant |
| elements of the Jacobian matrix | |
| PLATCOV | latent variable covariances, scores |
| PREDET | displays predetermined moment matrix |
| PRIMAT | displays output in matrix form |
| adds default displayed output | |
| PRIVEC | displays output in vector form |
| PSHORT | reduces default output (SHORT) |
| PSUMMARY | displays only fit summary (SUMMARY) |
| PWEIGHT | weight matrix |
| RESIDUAL= | residual matrix and distribution |
| SIMPLE | univariate statistics |
| STDERR | standard errors |
| TOTEFF | displays total and indirect effects |
| Miscellaneous Options | Short Description |
| ALPHAECV= | probability Browne & Cudeck ECV |
| ALPHARMS= | probability Steiger & Lind RMSEA |
| BIASKUR | biased skewness and kurtosis |
| DEMPHAS= | emphasizes diagonal entries |
| FDCODE | uses numeric derivatives for code |
| HESSALG= | algorithm for Hessian |
| NOSTDERR | computes no standard errors |
| RANDOM= | randomly generated initial values |
| SINGULAR= | singularity criterion |
| ASINGULAR= | absolute singularity information matrix |
| COVSING= | singularity tolerance of information matrix |
| MSINGULAR= | relative M singularity of information matrix |
| VSINGULAR= | relative V singularity of information matrix |
| SLMW= | probability limit for Wald test |
| START= | constant initial values |
The OUTEST= data set is described in the section "OUTEST= SAS-data-set". If you want to create a permanent SAS data set, you must specify a two-level name. Refer to the chapter titled "SAS Data Files" in SAS Language Reference: Concepts for more information on permanent data sets.
You can specify the latent variable score regression coefficients with PROC SCORE to compute factor scores. If you want to create a permanent SAS data set, you must specify a two-level name. Refer to the chapter titled "SAS Data Files" in SAS Language Reference: Concepts for more information on permanent data sets.
CAUTION: The INTERCEPT variable is included in the moment matrix as the variable with number n+1. Using the RAM model statement assumes that the first n variable numbers correspond to the n manifest variables in the input data set. Therefore, specifying the AUGMENT option assumes that the numbers of the latent variables used in the RAM or path model have to start with number n+2.

CAUTION: The moment matrix in the OUTSTAT= output data set does not contain the ridged diagonal.
| Value | Description | Divisor |
| DF | degrees of freedom | N - k - i |
| N | number of observations | N |
| WDF | sum of weights DF | |
| WEIGHT | WGT | sum of weights |
CAUTION: Using the WLS and DWLS methods with the ASYCOV=CORR option means that you are fitting a correlation (rather than a covariance) structure. Since the fixed diagonal of a correlation matrix for some models does not contribute to the model's degrees of freedom, you can specify the DFREDUCE=i option to reduce the degrees of freedom by the number of manifest variables used in the model. See the section "Counting the Degrees of Freedom" for more information.


For TECHNIQUE=CONGRA, the following updates can be used:
For TECHNIQUE=DBLDOG, the following updates (Fletcher 1987) can be used:
For TECHNIQUE=QUANEW, the following updates (Fletcher 1987) can be used:

Termination of all techniques (except the CONGRA technique) requires the normalized predicted function reduction to be small,
![{ [g(x^{(k)})]^' [G^{(k)}]^{-1} g(x^{(k)}) \over
\max(| f(x^{(k)})|,FSIZE) } \leq r](images/caleq62.gif)

Note that for releases prior to Release 6.11, the GCONV= option specified the absolute gradient convergence criterion.
| TECH= | UPDATE= | LSP default |
| QUANEW | DBFGS, BFGS | r = 0.4 |
| QUANEW | DDFP, DFP | r = 0.06 |
| CONGRA | all | r = 0.1 |
| NEWRAP | no update | r = 0.9 |
For more details, refer to Fletcher (1980, pp. 25 -29).
| TECH= | MAXFUNC default |
| LEVMAR, NEWRAP, NRRIDG, TRUREG | i=125 |
| DBLDOG, QUANEW | i=500 |
| CONGRA | i=1000 |
The default is used if you specify MAXFUNC=0. The optimization can be terminated only after completing a full iteration. Therefore, the number of function calls that is actually performed can exceed the number that is specified by the MAXFUNC= option.
| TECH= | MAXITER default |
| LEVMAR, NEWRAP, NRRIDG, TRUREG | i=50 |
| DBLDOG, QUANEW | i=200 |
| CONGRA | i=400 |
The default is used if you specify MAXITER=0 or missing.
The optional second value n is valid only for TECH=QUANEW with nonlinear constraints. It specifies an upper bound n for the number of iterations of an algorithm and reduces the violation of nonlinear constraints at a starting point. The default is n=20. For example, specifying
MAXITER= . 0means that you do not want to exceed the default number of iterations during the main optimization process and that you want to suppress the feasible point algorithm for nonlinear constraints.
| Output Options | PALL | default | PSHORT | PSUMMARY | |
| fit indices | * | * | * | * | * |
| linear dependencies | * | * | * | * | * |
| PREDET | * | (*) | (*) | (*) | |
| model matrices | * | * | * | * | |
| PESTIM | * | * | * | * | |
| iteration history | * | * | * | * | |
| PINITIAL | * | * | * | ||
| SIMPLE | * | * | * | ||
| STDERR | * | * | * | ||
| RESIDUAL | * | * | |||
| KURTOSIS | * | * | |||
| PLATCOV | * | * | |||
| TOTEFF | * | * | |||
| PCORR | * | ||||
| MODIFICATION | * | ||||
| PWEIGHT | * | ||||
| PCOVES | |||||
| PDETERM | |||||
| PRIVEC |
The Lagrange multiplier test (Bentler 1986; Lee 1985; Buse 1982)
provides an estimate of the
reduction that results from
dropping the constraint. For constant parameter constraints and
active boundary constraints, the approximate change of the parameter
value is displayed also. You can use this value to obtain an initial value
if the parameter is allowed to vary in a modified model.
For more information, see the section "Modification Indices".
CAUTION: The PALL option includes the very expensive computation of the modification indices. If you do not really need modification indices, you can save computing time by specifying the NOMOD option in addition to the PALL option.
You can use the STRUCTEQ statement to define which equations are structural equations. If you don't use the STRUCTEQ statement, PROC CALIS uses its own default definition to identify structural equations.
The term "structural equation" is not defined in a unique way. The LISREL program defines the structural equations by the user-defined BETA matrix. In PROC CALIS, the default definition of a structural equation is an equation that has a dependent left side variable that appears at least once on the right side of another equation, or an equation that has at least one right side variable that is the left side variable of another equation. Therefore, PROC CALIS sometimes identifies more equations as structural equations than the LISREL program does.
If the model contains structural equations, PROC CALIS also displays the
"Stability Coefficient of Reciprocal Causation,"
that is, the largest eigenvalue of the BB' matrix,
where B is the
causal coefficient matrix of the structural equations.
These coefficients are computed as in the LISREL VI
program of J
reskog and S
rbom (1985).
This displayed output is not included in
the output generated by the PALL option.
If the analyzed matrix is a correlation matrix (containing constant elements of 1s in the diagonal) and the model generates a predicted model matrix with q constant (rather than variable) elements in the diagonal, the degrees of freedom are automatically reduced by q. The output generated by the PREDET option displays those constant diagonal positions. If you specify the DFREDUCE= or NODIAG option, this automatic reduction of the degrees of freedom is suppressed. See the section "Counting the Degrees of Freedom" for more information.

If the Jacobian is more than 25% dense, the dense analytic algorithm, HA=1, is used by default. The HA=1 algorithm is faster than the other dense algorithms, but it needs considerably more memory for large problems than HA=2,3,4. If the Jacobian is more than 75% sparse, the sparse analytic algorithm, HA=11, is used by default. The dense analytic algorithm HA=4 corresponds to the original COSAN algorithm; you are advised not to specify HA=4 due to its very slow performance. If there is not enough memory available for the dense analytic algorithm HA=1 and you must specify HA=2 or HA=3, it may be more efficient to use one of the quasi-Newton or conjugate-gradient optimization techniques since Levenberg-Marquardt and Newton-Raphson optimization techniques need to compute the Hessian matrix in each iteration. For approximate standard errors and modification indices, the Hessian matrix has to be computed at least once, regardless of the optimization technique.
The algorithms HA=5 and HA=6 compute approximate derivatives by using forward difference formulas. The HA=5 algorithm corresponds to the analytic HA=1: it is faster than HA=6, however it needs much more memory. The HA=6 algorithm corresponds to the analytic HA=2: it is slower than HA=5, however it needs much less memory.
Test computations of large sparse problems show that the sparse algorithm HA=11 can be up to ten times faster than HA=1 (and needs much less memory).


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