Mplus Users Guide v6.. - Muthén & Muthén

CHAPTER 15the VARIABLE command and variables created using the DEFINEcommand and the DATA transformation commands. The exception isthat variables used with the SUBPOPULATION option must bevariables from the NAMES statement of the VARIABLE command.Following is a description of these options and their specifications.STRATIFICATIONThe STRATIFICATION option is used with TYPE=COMPLEX toidentify the variable in the data set that contains information about thesubpopulations from which independent probability samples are drawn.Following is an example of how the STRATIFICATION option is used:STRATIFICATION IS region;where region is the variable that contains stratification information.CLUSTERThe CLUSTER option is used with TYPE=COMPLEX andTYPE=TWOLEVEL to identify the variables in the data set that containclustering information. Two cluster variables are allowed toaccommodate two-stage cluster sampling with TYPE=COMPLEXTWOLEVEL. Following is an example of how the CLUSTER option isused in a single-stage cluster design:CLUSTER IS school;where school is the variable that contains cluster information in a singlestagecluster design.TYPE=COMPLEX TWOLEVEL can be used with two cluster variables,one stratification and two cluster variables, and one stratification andone cluster variable. Following is an example of how the CLUSTERoption is used in a two-stage cluster design with TYPE=COMPLEXTWOLEVEL:CLUSTER IS psu household;where psu is the primary sampling unit and household is the secondarysampling unit. The secondary sampling unit must be nested within the500