Scientific Software International (SSI) publishes statistical data analysis software: LISREL (structural equation model/SEM, survey generalized linear model/SGLIM), 
HLM (hierarchical linear modeling, multilevel model), SuperMix (mixed models, mixed-effects program, MIXREG, MIXOR, MIXNO and MIXPREG) and Item Response Theory/IRT (BILOG-MG, MULTILOG, PARSCALE)Scientific Software International (SSI) publishes statistical data analysis software: LISREL (structural equation model/SEM, survey generalized linear model/SGLIM), 
HLM (hierarchical linear modeling, multilevel model), SuperMix (mixed models, mixed-effects program, MIXREG, MIXOR, MIXNO and MIXPREG) and Item Response Theory/IRT (BILOG-MG, MULTILOG, PARSCALE)Scientific Software International (SSI) publishes statistical data analysis software: LISREL (structural equation model/SEM, survey generalized linear model/SGLIM), 
HLM (hierarchical linear modeling, multilevel model), SuperMix (mixed models, mixed-effects program, MIXREG, MIXOR, MIXNO and MIXPREG) and Item Response Theory/IRT (BILOG-MG, MULTILOG, PARSCALE)


D  Data
  • The data consist of indicators of alcohol and marijuana usage of 1608 high school students during 2001 as recorded in the Monitoring The Future (MTF) study which is conducted by the Institute for Social Research at the University of Michigan.
  • More details about the data are available at http://www.icpsr.umich.edu/cgi/archive.prl?study=3088&path=SAMHDA.
  • The following variables are included:
    • ALCLIFS: On how many occasions have you had alcoholic beverages to drink in your lifetime?
    • ALC12MOS: On how many occasions have you had alcoholic beverages to drink in the past 12 months?
    • ALC30DS: On how many occasions have you had alcoholic beverages to drink in the past 30 days?
    • XMJLIFS: On how many occasions have you used marijuana in your lifetime?
    • XMJ12MOS: On how many occasions have you used marijuana in the past 12 months?
    • XMJ30DS: On how many occasions have you used marijuana in the past 30 days?
    • TICK12MO: Within the last 12 months, how many times have you received a ticket (or been stopped and warned) for moving violations?
    • ACCI12MO: Within the last 12 months, how many times you were involved in an accident while driving?
  • The raw data are listed in the file select.PSF in the TUTORIAL folder.
  • The first couple of lines of select.PSF are shown in the following PSF window.

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M  Model
  • The five indicators are modeled to measure the alcohol usage (ALCUSAGE)and marijuana usage (MRJUSAGE).
  • Alcohol and marijuana usage are modeled as causes of the number of moving violations and accidents.
  • A path diagram of the model is shown below.

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A  Analysis

Specifying the complex survey design

  • Use the Open option on the File menu to load the Open dialog box.
  • Select the PRELIS data (*.psf) option from the Files of type: drop-down list box.
  • Browse for the file select.PSF in the TUTORIAL folder.
  • Click on the Open button to open the select.PSF in a PSF window.
  • Click on the Survey Design option on the Data menu to load Survey Design dialog box.
  • Select the label region from the Variables in data: list box.
  • Click on the Add button of the Stratification variable section.
  • Select the label school from the Variables in data: list box.
  • Click on the Add button of the Cluster variable section.
  • Select the label newwgt from the Variables in data: list box.
  • Click on the Add button of the Design weight section to produce the following Survey Design dialog box.

  • Click on the OK button to return to the PSF window.
  • Click on the Save option on the File menu.

Fitting the structural equation model

  • Select the New option on the File menu to load the New dialog box.
  • Select the Path Diagram option from the list box on the New dialog box to load the Save As dialog box.
  • Enter the name SELECT.PTH in the File name string field.
  • Click on the Save button to open an empty PTH window.
  • Select the Title and Comments option on the Setup menu to load the Title and Comments dialog box.
  • Enter the title A Model for Traffic Tickets and Accidents in the Title string field.
  • Click on the Next button to load the Group Names dialog box.
  • Click on the Next button to load the Labels dialog box.
  • Click on the Add/Read Variables button to load the Add/Read Variables dialog box.
  • Select the PRELIS System File option in the Read from file: drop-down list box.
  • Click on the Browse button to load the Browse dialog box.
  • Select the file select.PSF in the TUTORIAL folder.
  • Click on the Open button to return to the Add/Read Variables dialog box.
  • Click on the OK button to return to the Labels dialog box.
  • Click on the Add Latent Variables push button to load the Add Variables dialog box.
  • Enter the label ALCUSAGE in the string field.
  • Click on the OK button to return to the Labels dialog box.
  • Click on the Add Latent Variables push button to load the Add Variables dialog box.
  • Enter the label MRJSUAGE in the string field.
  • Click on the OK button to return to the Labels dialog box.
  • Click on the Add Latent Variables push button to load the Add Variables dialog box.
  • Enter the label ACCIDENT in the string field.
  • Click on the OK button to return to the Labels dialog box.
  • Click on the Add Latent Variables push button to load the Add Variables dialog box.
  • Enter the label TICKETS string field.
  • Click on the OK button to produce the following Labels dialog box.

  • Click on the OK button to return to the PTH window for SELECT.PTH.
  • Check the Y check boxes of acci12mo and tick12mo respectively.
  • Check the Eta check boxes of ACCIDENT and TICKETS respectively.
  • Click, drag and drop the labels of the observed variables one at a time into the PTH window.
  • Click, drag and drop the labels of the latent variables one at a time into the PTH window.
  • Select the arrow icon on the Drawing toolbar.
  • Click and drag 2 indicator paths from the latent variable ALCUSAGE to alclifs and alc30ds respectively.
  • Click and drag 3 indicator paths from the latent variable MRJUSAGE to smjlifs, xmj12mos and xmj30ds respectively.
  • Click and drag 1 structural path from the latent variable ALCUSAGE to TICKETS.
  • Click and drag 1 structural path from the latent variable MRJUSAGE to ACCIDENT.
  • Click and drag 1 indicator path from the latent variable ACCIDENT to acci12mo and right click the path to set the value fixed to 1.0.
  • Click and drag 1 indicator path from the latent variable TICKETS to tick12mo and right click the path to set the value fixed to 1.0.
  • Right click the error arrow of acci12mo and fix the error variance of acci12mo to 0.
  • Right click the error arrow of tick12mo and fix the error variance of tick12mo to 0.
  • Select the double arrow icon on the Drawing toolbar.
  • Click and drag 1 path between the error arrows of alclifs and alc30ds.
  • Click and drag 1 path between the error arrows of xmj12mos and xmj30ds to produce the following PTH window.

  • Select the Build SIMPLIS Syntax option on the Setup menu to open the following SPJ window.

  • Click on the Run LISREL icon on the main toolbar to produce the following PTH window.

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