Dear experts,
I am currently trying to fit an unconditional growth curve model (as a first step before looking forward to more complex models). As you can see in the attachments, none of my attempts worked out - no matter whether I took a linear, quadratic or cubic model. I used the following sem commands for computing these curves:

sem (Intercept@1 Slope@0 -> deprivation1) ///
(Intercept@1 Slope@1 -> deprivation2) ///
(Intercept@1 Slope@2 -> deprivation3) ///
(Intercept@1 Slope@3 -> deprivation4) ///
(Intercept@1 Slope@4 -> deprivation5) ///
(Intercept@1 Slope@5 -> deprivation6) ///
(Intercept@1 Slope@6 -> deprivation7) ///
(Intercept@1 Slope@7 -> deprivation8) ///
(Intercept@1 Slope@8 -> deprivation9) ///
(Intercept@1 Slope@9 -> deprivation10) ///
(Intercept@1 Slope@10 -> deprivation11) ///
(Intercept@1 Slope@11 -> deprivation12) ///
(Intercept@1 Slope@12 -> deprivation13), ///
method(mlmv) noconstant means(Intercept Slope)

sem (Intercept@1 Linear@0 Quadratic@0 -> deprivation1) ///
(Intercept@1 Linear@1 Quadratic@1 -> deprivation2) ///
(Intercept@1 Linear@2 Quadratic@4 -> deprivation3) ///
(Intercept@1 Linear@3 Quadratic@9 -> deprivation4) ///
(Intercept@1 Linear@4 Quadratic@16 -> deprivation5) ///
(Intercept@1 Linear@5 Quadratic@25 -> deprivation6) ///
(Intercept@1 Linear@6 Quadratic@36 -> deprivation7) ///
(Intercept@1 Linear@7 Quadratic@49 -> deprivation8) ///
(Intercept@1 Linear@8 Quadratic@64 -> deprivation9) ///
(Intercept@1 Linear@9 Quadratic@81 -> deprivation10) ///
(Intercept@1 Linear@10 Quadratic@100 -> deprivation11) ///
(Intercept@1 Linear@11 Quadratic@121 -> deprivation12) ///
(Intercept@1 Linear@12 Quadratic@144 -> deprivation13), ///
method(mlmv) noconstant means(Intercept Linear Quadratic)

sem (Intercept@1 Linear@0 Quadratic@0 Cubic@0 -> deprivation1) ///
(Intercept@1 Linear@1 Quadratic@1 Cubic@1 -> deprivation2) ///
(Intercept@1 Linear@2 Quadratic@4 Cubic@8 -> deprivation3) ///
(Intercept@1 Linear@3 Quadratic@9 Cubic@27 -> deprivation4) ///
(Intercept@1 Linear@4 Quadratic@16 Cubic@64 -> deprivation5) ///
(Intercept@1 Linear@5 Quadratic@25 Cubic@126 -> deprivation6) ///
(Intercept@1 Linear@6 Quadratic@36 Cubic@216 -> deprivation7) ///
(Intercept@1 Linear@7 Quadratic@49 Cubic@343 -> deprivation8) ///
(Intercept@1 Linear@8 Quadratic@64 Cubic@512 -> deprivation9) ///
(Intercept@1 Linear@9 Quadratic@81 Cubic@729 -> deprivation10) ///
(Intercept@1 Linear@10 Quadratic@100 Cubic@1000 -> deprivation11) ///
(Intercept@1 Linear@11 Quadratic@121 Cubic@1331 -> deprivation12) ///
(Intercept@1 Linear@12 Quadratic@144 Cubic@1728 -> deprivation13), ///
method(mlmv) noconstant means(Intercept Linear Quadratic Cubic)

Thereby deprivation* is an index of twenty items for material deprivation, one for each of the 13 panel waves.
Do any of you have any ideas which kind of growth function could be more appropriate to my data?

Thanks for your help and best regards
Patrick