Hello everyone,
I conducted a vignette study (=hypothetical scenarios with different characteristics/attributes that are evaluated). Each participant evaluated three vignettes (scenario accepted or not). A scenario always consists of two dimensions (also attributes) with three characteristics (also levels) each. Now I want to calculate the effects of the vignette content/levels on the vignette evaluation.
Since the data is nested with three evaluations per participant, I am performing a two-level logistic regression (level 1: vignette evaluations, level 2: participants). The SPSS output of the covariance parameter overview states that I have estimated 25 fixed effects and 1 random effect. However, I only have 12 (dichotomous) fixed effects in the model. Why are the two levels of the dichotomous variable (one of which is 0) counted as two effects? Is the model penalized for the high number of included predictors (i.e., higher -2ll, AIC, BIC)?
Thanks in advance and best regards,
Julia