Mplus Users Guide v6.. - Muthén & Muthén

Examples: Growth Modeling And Survival Analysisentries in the table represent the ages. In this example, ages 10 to 18 arerepresented.M.O./ 2000 2002 2004 2006Cohort1988 12 14 16 181989 11 13 15 171990 10 12 14 16The model that is estimated uses the time axis of age as shown in thetable below where rows represent cohort and columns represent age.The entries for the first three rows in the table are the years of themeasurement occasions. The entries for the last row are the time scoresfor a linear model.Age/Cohort10 11 12 13 14 15 16 17 181988 2000 2002 2004 20061989 2000 2002 2004 20061990 2000 2002 2004 2006TimeScore0 .1 .2 .3 .4 .5 .6 .7 .8As shown in the table, three ages are represented by more than onecohort. Age 12 is represented by cohorts 1988 and 1990 measured in2000 and 2002; age 14 is represented by cohorts 1988 and 1990measured in 2002 and 2004; and age 16 is represented by cohorts 1988and 1990 measured in 2004 and 2006. This information is needed toconstrain parameters to be equal in the multiple group model.The table also provides information about the time scores for eachcohort. The time scores are obtained as the difference in age betweenmeasurement occasions divided by ten. The division is used to avoidlarge time scores which can lead to convergence problems. Cohort 1990provides information for ages 10, 12, 14, and 16. The time scores forcohort 2000 are 0, .2, .4, and .6. Cohort 1989 provides information forages 11, 13, 15, and 17. The time scores for cohort 1989 are .1, .3, .5,and .7. Cohort 1988 provides information for ages 12, 14, 16, and 18.The time scores for cohort 1988 are .2, .4, .6, and .8.131