Developed by Paul Bailey, Charles Blankenship, Eric Buehler, Ren C'deBaca, Nancy Collins, Ahmad Emad, Thomas Fink, Huade Huo, Frank Fonseca, Julian Gerez, Sun-joo Lee, Michael Lee, Jiayi Li, Yuqi Liao, Alex Lishinski, Thanh Mai, Trang Nguyen, Emmanuel Sikali, Qingshu Xie, Sinan Yavuz, Jiao Yu, and Ting Zhang

Paul Bailey, Ahmad Emad, Ting Zhang, Qingshu Xie

Paul Bailey, Ahmad Emad, Ting Zhang, Qingshu Xie

Developed by Paul Bailey and Harold Doran\footnote{This publication was prepared for NCES under Contract No. ED-IES-12-D-0002 with the American Institutes for Research. Mention of trade names, commercial products, or organizations does not imply endorsement by the U.S. Government.}

Developed by Paul Bailey, Claire Kelley, and Trang Nguyen\footnote{This publication was prepared for NCES under Contract No. ED-IES-12-D-0002 with the American Institutes for Research. Mention of trade names, commercial products, or organizations does not imply endorsement by the U.S. government.} \footnote{The authors would like to thank Mike Cohen and Dan Sherman for reviewing this document, and Yuqi Liao, Bitnara Park, and Jiayi Li for their help using mixed models in other software packages.}

Developed by Paul Bailey\footnote{This publication was prepared for NCES (National Center for Education Statistics) under Contract No. ED-IES-12-D-0002 with American Institutes for Research. Mention of trade names, commercial products, or organizations does not imply endorsement by the U.S. government.} \footnote{The authors would like to thank Mike Cohen for reviewing this document.}