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Hello, Mplus seems to be the only software able to estimate this model where a twolevel mediation (z> x > y) is combined with a crosslevel interaction (z> slope). My example code is straightforward: ANALYSIS: TYPE = TWOLEVEL RANDOM; MODEL: %WITHIN% SLOPE  y ON x; %BETWEEN% y ON x; y ON z; x ON z; SLOPE ON z; What is perhaps not so straightforward (& hopefully not outside the scope of this forum) is the question on the decomposition of the effects estimated with such a model: Given that the slope of x varies between clusters and is predicted by z, how should one calculate the indirect effect from z on y? Many thanks, Tino 


If I look at the formulas correctly, I think the indirect effect from z to y via x is simply the usual product of slopes for y ON x and x on z. The random slope does not come into the picture for the indirect effect because there is not mediation on Within but on Between. 

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