Here are a couple of articles forthcoming in Party Politics:
“Mapping issue salience divergence in Europe from 1945 to the present” by Jacob R Gunderson. Article doesn’t appear to be paywalled. Good evidence that seems to match, in Europe, of the US pattern of nationalization (or internationalization) of a geographical reduction in issue heterogeneity.
“Blurred positions: The ideological ambiguity of valence populist parties”
Mattia Zulianello and Erik Gahner Larsen. I really like the idea of measuring/analyzing how parties “deliberately take blurry positions” as I think this does not get enough attention in the text analysis literature. Interestingly, as well, they find that ambiguity occurs alongside anti-corruption appeals, “the most paradigmatic example of a non-positional dimension.” I have often felt that the issue ownership literature should take the tendency of parties to equivocate or use less declarative language as evidence of being on the losing side of an issue divide.
State Party Platform Project 