Hey @YipingNUS ! Excellent work here. I was looking at the IAB content taxonomy website and I see that they have released up to version 3.0. When I look at old versions (say 2.0), the number of tier 1 categories is around 35 and 560 for tier 2. However, in your paper (and in the data), there are only 23 tier 1 categories and 354 tier 2 categories.
Which version of the IAB taxonomy did you use for this data? 1.0? When I look at the website, it says that version 1.0 is deprecated, but if this is the case, do you know if there's a mapping between the categories in version 1.0 and 2.0? Thanks!