Some remarks on generic structures
David M. Evans, Mark Wing Ho Wong · Journal of Symbolic Logic · 2009
Abstract We show that the ℵ0-categorical structures produced by Hrushovski's predimension construction with a control function fit neatly into Shelah's SOPn hierarchy: if they are not simple, then they have SOP3 and NSOP4. We also show that structures produced without using a control function can be undecidable and have SOP.