While reading the tutorial in How APSI Works/Native Ideal, the following is mentioned: The sender holds a set {Y_i} of items and the receiver holds a single item X.... I realised that the logic of the sets is reversed according to the article Labeled PSI of Homomorphic Encryption with Reduced Computation and Communication
Although this does not affect the tutorial itself, in general the articles on this topic follow this logic: Sender holds X and Receiver holds Y.
However, I don't know if this is a mistake or a misinterpretation on my part, greetings.