I have 2 questions:
1) How many experimental questions are there?
2) How are questions ranked? Is it based solely on the perecentage of people getting those question correctly when the question was experimental?
What I am concerned about are badly worded or just bad questions which may make a question be ranked at a high level, because people get it wrong as opposed to a tough question that is tough because it tests your understanding of the material and your application of the material in a creative unique way.
1) if i remember correctly about 25% of the questions are experimental
2) questions goe through extensive review and editing before entering the test as experimental questions. the questions are "ranked" according to how many of test takers got it right TAKING INTO ACCOUNT their scores.
in other words - through lots of test takers they get a graph of %of test takers per score who got he question right.
i guess that if the there is a problem with the question the graph won't look nice, or at least be suspicious