• Journal of the Korean Statistical Society
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• 제27권2호
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• pp.237-249
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• 1998

Process adjustment has been widely used in production processes in order to set the output characteristic as close as to the target. Box and Kramer(1992) developed a feedback adjustment control procedure for process adjustment. We generalize their procedure by using a rational subgrouping of sequential observations. In this paper the feedback control rule of the rational subgrouping is proposed and the overall expected cost is evaluated. Also properties of the proposed control scheme are illustrated and compared to Box and Kramer's in the context of the expected cost.

• 응용통계연구
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• 제2권1호
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• pp.18-34
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• 1989

서로 같은 분산을 가지며 정규분포를 따르는 4개의 처리평균의 대응비교에 관한 연구로서, 삼중 t-분포를 이용하여 동시포함 범위 확률값이 정확히 $1-\alpha$를 갖는 통계적 계산방법과 기법을 고찰하였다. 이 기법을 이용하여 처리사이의 표본 갯수를 변화시켜 대응되는 정확한 신뢰구간을 구하며 기존의 신뢰구간의 길이 비교, 실험적 오차 비, 효율성을 조사하였다.

• 대한족부족관절학회지
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• 제19권2호
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• pp.63-68
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• 2015

Purpose: The purpose of this study was to report impacts of the amount of displacement of percutaneous osteotomy on the clinical and radiologic results in the treatment of bunionette deformities. Materials and Methods: We retrospectively reviewed 36 cases of bunionette deformities treated with percutaneous modified Kramer osteotomies from 2009 to 2013. We measured amounts of displacement on anteroposterior and lateral plain radiographs as well as multiple parameters which represent degrees of the bunionette deformities. We also recorded radiological healing time, clinical healing time, residual symptoms, and the time of returning to daily activity. Results: No meaningful correlation was found between severity of preoperative deformity and amount of displacement of the osteotomy. The amount of displacement on a horizontal plane did not affect the healing time, duration of symptoms, or time of returning to daily activity. However, large sagittal displacement was related to duration of postoperative symptoms. Conclusion: Findings of this study suggest that the displacement in percutaneous osteotomy for bunionette deformity does not affect clinical results and healing time. We believe that we do not need to be excessively cautious about how large the displacement we make during the percutaneous modified Kramer osteotomy for the bunionette deformity.