The paper reviews gauge R&R studies by two-factor mixed models including random and fixed factors. The two-factor mixed models include restricted models and unrestricted models considering the interaction of two factors. This study also classifies the models according to the number of factors, and the combination of various factors such as random factor, fixed factor, block factor and repetition type.

Abstract
 1. 서론
 2. 2인자 측정모형
  2.1 1인자 모형
  2.2 2인자 모형
 3. A가 랜덤변량 인자인 경우 혼합 측정모형
  3.1 제약 설계
  3.2 비제약 설계
 4. B가 랜덤변량 인자인 경우 혼합 측정모형
  4.1 제약 설계
  4.2 비제약 설계
 5. 블록되풀이 혼합 측정모형
 6. 결론
 7. 참고문헌

• 최성운 | Sungwoon Choi