According to the ETS website (https://www.ets.org/gre/subject/scores/how/
), 1/4th of a point is no longer subtracted from one's score for incorrect answers on 2017-2018 GRE subject tests. On the other hand, 2017 Math GRE practice materials, such as the current Princeton Review book, indicate that incorrect answers still cost 1/4th of a point.
While I would be inclined to trust the ETS website, would anyone know of an authoritative source with discusses the scoring of the 2017-2018 Math Subject GRE specifically? Naturally, it would be nice to know which scoring convention will be used, as this would effect one's strategy on the test.
Thanks in advance.