Hola, We have a potential concern with analyzing our data: Quick Backgroud: Research Design is 2x2 Mixed Model involving the effects of central blind spots on Visual Search. The subjects are searching for a target (O) embedded among distracters (C’s). The set sizes we have used are 1, 8, and 32 (1 stimuli on screen =1set size; 8 stimuli on screen= 8 set size and so forth). Problem: The potential concern is the set sizes (predictor variables) are NON-LINEAR in spacing (unequal). Our plan is to use GLM Repeated Measures to analyze the data, but we’re wondering if this GLM model can be used with the set size non-linearity…………another words does the GLM model implicitly assume linear spacing with its analyses? If yes, what are the potential solutions? t/y Dave