LISREL is a statistical package designed to estimate parameters of structural-equation models (SEM). The current version of LISREL running on strauss is LISREL 8.72. LISREL is accompanied by the PRELIS package, currently PRELIS Version 2.7, by the MULTILEV package, currently Version 7 and by the SURVEYGLIM, version 1.1.
PRELIS does preprocessing for LISREL, MULTILEV and SURVEYGLIM. One of the primary uses of PRELIS is to estimate polychoric correlation matrices for ordinal or binary input variables. The output correlation matrix may be used as input to the other programs. PRELIS performs several other analyses including calculation of moment matrices, linear, logistic and probit regression and censored regression.
MULTILEV estimates both linear and nonlinear multilevel models using as input a PRELIS system file (PSF) produced by PRELIS -- can be used to calculate correct inferential statistics for complex sampling designs.
SURVEYGLIM estimates generalized linear models from data collected by complex sample designs, or data collected by SRS. SURVEYGLIM also uses PRELIS system files (PSF) as input.
LISREL, PRELIS, MULTILEV and SURVEYGLIM are available on Strauss. The Windows version is available in the Research & Data Management Services Lab (room 002C Smith Hall).
LISREL, PRELIS, MULTILEV, and SURVEYGLIM instructions must be entered into a file, referred to as a command file. The command file contains syntax that instructs the programs what computations to carry out. The full-format of the UNIX command for each of the four programs is the same, enter the program name followed by the full name of the command file and the full name of the output file, like this --
prelis model1P.pr2 model1P.out
lisrel model1L.ls8 model1L.out
multilev MModel.pr2 MModel.out
surveyglim surveyAnalysis.pr2 surveyAnalysis.out
The first command is a prelis run. The command file is named model1P.pr2 and the output is written to a file named model1P.out. The other three pairs of files are analogously named.
You also may enter the command to execute one of these programs without listing any command-line arguments:
lisrel prelis multilev surveyglim
In this case, the program prompts for the names of the command file and output file. If you enter just one file name, the program assumes it is the command file and prompts for the name of the output file.
One of the example command files that comes with LISREL is called EX82A.LS8. After the command file is created, LISREL may be run using it as input. To run this analysis, type --
lisrel EX82A.LS8 EX82A.out
at the UNIX prompt. In this example, the output file is called, EX82A.out.
Errors are written to the output file and include a message containing: F_A_T_A_L E_R_R_O_R:.
To view the output on the screen, use the UNIX pager less, for example
less EX82A.out
Use the spacebar to go down one screen, the letter b to go back one screen and the letter q to quit. For searches, use the forward slash followed by the string you want to find. For example
/Covariance Matrix
To ignore case in the searches, type -i before starting a search. The ignore-case setting remains in effect until you exit or type -i again.
You also may view the output with a UNIX editor such as pico.
To print the output at the Smith Hall printers, type
lpr EX82A.out
Pick up the copy at the Smith Hall IO counter at the bottom of the middle stairs.
To print at another destination, use the -P flag followed by the name of the printer queue. For example
lpr -P whlps EX82A.out
sends the file to room 009 in Willard Hall. A list of the printers is online.
Note: It usually is helpful to open more than one terminal window on strauss. Edit the command file from one window, and save it without exiting the editor. Then execute the program and view the output in the other window.
Many analyses use output generated by PRELIS as input to LISREL, MULTILEV or SURVEYGLIM. In these instances, prelis produces a system file which is used as input for one of the other programs.
The following example uses PRELIS to estimate a polychoric correlation matrix and an asymptotic covariance matrix from raw-data input. The output matrices from PRELIS are input to LISREL. The PRELIS command file is called EX72B.PR2. The LISREL command file which uses this output from PRELIS is called EX72B.LS8.
To get results for this analysis, run PRELIS first, so it can produce the output polychoric correlation (PANELUSA.PME) and asymptotic covariance matrices (PANELUSA.ACE). Then run LISREL. In this example, the PRELIS and LISREL command files have the same root-part of their file names. It's therefore advisable to direct the output to different files. Otherwise, the LISREL run would overwrite the output from the PRELIS run.
prelis EX72B.PR2 EX72Bpr.out lisrel EX72B.LS8 EX72Bls.out
In this example, the output from the PRELIS run is stored in EX72Bpr.out. And output from the LISREL run is stored in EX72Bls.out.
The MULTILEV program operates in a fashion analogous to running LISREL with input produced by PRELIS. Input to the MULTILEV program is an output file produced by PRELIS. And, the example MULTILEV command files that come with the lisrel instalation have the same extension used for PRELIS command files, (.PR2). So, first run PRELIS to process the ASCII (raw) data file. Then run MULTILEV.
One of the examples that comes with LISREL carries out a multilevel analysis of income. The commands for the initial PRELIS run are stored in a file named INCOME1A.PR2. And the commands for the MULTILEV run are stored in INCOME1.PR2
To run this analysis, first execute PRELIS
prelis INCOME1A.PR2 INCOME1A.out
Then run MULTILEV
multilev INCOME1.PR2 INCOME1.out
Since the root-part of the two command file names differ, the second run does not overwrite the output from the first run. In this example, output from the PRELIS run is stored in the file named INCOME1A.out. And output from the MULTILEV run is stored in INCOME1.out.
The SURVEYGLIM program also operates in a fashion analogous to running LISREL using input produced by PRELIS. Input to the SURVEYGLIM program is an output file produced by PRELIS. And, the SURVEYGLIM command files have the same extension used for PRELIS command files, (.PR2). So, first run PRELIS to process the ASCII (raw) data file. Then run SURVEYGLIM.
One of the examples that comes with LISREL carries out a SURVEYGLIM analysis of substance abuse. The commands for the initial PRELIS run are stored in a file named ABUSE1.PR2. And the commands for the SURVEYGLIM run are stored in SGLIMEX1.PR2
To run this analysis, first execute PRELIS
prelis ABUSE1.PR2 ABUSE1.out
Then run SURVEYGLIM which uses output form the PRELIS run as input
surveyglim SGLIMEX1.PR2 SGLIMEX1.out
Output from the first run is stored in the file named ABUSE1.out. And output from the second run is stored in SGLIMEX1.out.
See the web site for Scientific Software (SSI). for more information including access to documentation and many examples. The example command files and other useful documentation may be downloaded.
If you need help quickly, you may call the IT Help Center at 831-6000 between 8 a.m. and 5 p.m., Monday through Friday. Or, you can submit a question through e-mail.