Ideological Radicality is a secondary stat, that is, a stat derived directly from other stats that can have different weighting. It is mostly linked to your Freedoms (the higher/lower each is, the better, so that the more radical cathegories are not only Anarchies or Psychotic Dictatorships, but also any nation type obtained with a combination of high and low freedoms, such as Benevolent Dictatorship, Left-Wing Utopia, Tyranny by Majority...). Digging old threads, it seems that in the past that was the only factor related to Ideological Radicality. However, it is now influenced by more stats with (apparently) a much lower weighting. This is especially noticeable if your nation is really radical, as if you keep pushing in that particular direction freedoms frequently remain static, whereas Ideological Radicality can have usually minor rises or drops.
So, it is indeed possible to keep increasing your Ideological Radicality once you've hit maximum/minimum freedoms. Does anybody how more or less how? Which types of issues seem to modify IR (unrelated to freedoms)?
) will have high radicality scores, and a run-of-the-mill Inoffensive Centrist Democracy or New York Times Democracy will have low radicality and high averageness. From my personal experience, it seems to vary only when one of the three freedoms is changed, though I'm not sure what the official answer is.