The "Identifying Indicators That Predict Postsecondary Readiness and Success in Arkansas" study examined the extent to which Arkansas's middle school and high school indicators of postsecondary readiness predict a student's postsecondary readiness outcome and success outcomes. The study estimated the accuracy and strength of the middle school and high school indicators for predicting the outcomes. While fewer than half of students met the Arkansas postsecondary readiness standard, more than half enrolled in college and about half persisted for more than one term within eight years of beginning grade 6. This document presents the following three appendixes that accompany the study: (1) Data and methods; (2) Supporting tables; and (3) Alternative model results. [For the full report, see ED613040. For the Study Snapshot, see ED613042.]