The major purpose of this study is to examine the quality of ratings assigned to CR (constructed-response) questions in large-scale assessments from the perspective of Rasch Measurement Theory. Rasch Measurement Theory provides a framework for the examination of rating scale category structure that can yield useful information for interpreting the meaning of ratings assigned in large-scale performance assessment contexts. This study uses data collected as a part of the reader reliability studies (Miao & Odumade, 2011) based on the 2010 administration of the AP® Statistics Exam (N = 238 students, N = 156 raters). The following research questions are addressed: (1) Do the raters on the AP Statistics Exam vary in severity? (2) Do the CR questions on the AP Statistics Exam vary in difficulty? (3) Is the structure of the rating scale comparable across the CR questions? An appendix contains two additional tables. [This paper was presented at the annual meeting of the American Educational Research Association in Vancouver, British Columbia, Canada, April 2012.]