Mplus Users Guide v6.. - Muthén & Muthén

CHAPTER 15cohort. In the example above, individuals in cohort 67 should haveinformation on y1, y2, and y3; individuals in cohort 68 should haveinformation on y4, y5, and y6; and individuals in cohort 69 should haveinformation on y2, y3, and y4. Individuals who have missing values onany variable for which they are expected to have information areeliminated from the analysis. The copattern variable must contain onlyinteger values.COHRECODEThe COHRECODE option is used in conjunction with either theCOHORT or COPATTERN options to recode the values of the cohort orcopattern variable. The COHRECODE option is specified as follows:COHRECODE = (1=67 2=68 3=69 4=70);where the original values of 1, 2, 3, and 4 of the cohort or copatternvariable are recoded to 67, 68, 69, and 70, respectively. If theCOHRECODE option is used, all values of the original variable must berecoded to be included in the analysis. Observations with values that arenot recoded will be eliminated from the analysis.TIMEMEASURESThe TIMEMEASURES option is used with multiple cohort data tospecify the years in which variables to be used in the analysis weremeasured. It is used in conjunction with the COHORT andCOPATTERN options to determine the ages that are represented in themultiple cohort data set. Variables used with the TIMEMEASURESoption must be variables from the NAMES statement of the VARIABLEcommand. Following is an example of how the TIMEMEASURESoption is specified:TIMEMEASURES = y1 (82) y2 (84) y3 (85) y4 (88) y5 (94);where y1, y2, y3, y4, and y5 are original variables that are to be used inthe analysis, and the numbers in parentheses following each of thesevariables represent the years in which they were measured. In thissituation, y1, y2, y3, y4, and y5 are the same measure, for example,frequency of heavy drinking measured on multiple occasions.478