問24
頻出度★★☆
シックスシグマ活動に関する説明として, 適切なものはどれか。
平成24年度 春期 ITパスポート試験 問24
ストラテジ系経営戦略マネジメント › 経営管理システム
This question's explanation and your answers so far.
解説
問 24
Incorrectア
“Predict in advance the obstacles that may occur (in a work process), and plan countermeasures for them” describes risk management (identifying, analyzing, and evaluating risks and drawing up risk response plans such as avoidance or mitigation); it is also the idea behind a contingency plan that prepares for the case where a problem does occur. Its focus is preparing beforehand for events that may happen in the future, and it has neither the measurement of quality data nor the statistical suppression of variation, so it is wrong as a description of Six Sigma.
Incorrectイ
“Form a group of workplace members and continuously solve the various problems that arise within the workplace” describes QC circle activities (small-group activities). This is an activity that originated in Japan, in which frontline employees voluntarily form small groups and continuously improve the problems close at hand; it is also the practice that supports TQM (Total Quality Management) on the shop floor. This description focuses on how the group is organized and on the continuity of the activity, and so differs from Six Sigma, whose core is quantifying quality and suppressing variation.
- ウ
正解 The correct answer is ウ. Six Sigma is a management method for raising quality that statistically controls and improves the quality of work or of a process. The “sigma (σ)” its name comes from is the standard deviation of statistics, the symbol for how large the “variation” in results is, and Six Sigma means a state in which a margin of six standard deviations fits inside the tolerance range of the specification, that is, aiming at an extremely low defect level of only a few defects per one million opportunities. The activity therefore proceeds as follows: first measure the quality of the target work as numbers (quantitative data) instead of by intuition or experience, then analyze and remove the causes that produce variation in those numbers, and stabilize and raise quality by holding the variation down. Choice ウ, “Quantify the quality of the target work, and improve work quality by suppressing its variation,” states exactly this feature, so it is appropriate. As a practical procedure, DMAIC (Define → Measure → Analyze → Improve → Control) is well known.
Incorrectエ
“By turning quality-related activities into defined procedures, documents, and records, achieve quality assurance and improved customer satisfaction” describes a quality management system (QMS), represented by ISO 9001. Its purpose is to build a mechanism that assures quality by showing through documents and records that the work was carried out as decided; it is not in itself an activity that statistically reduces variation. It is therefore wrong as a description of Six Sigma.
ここがポイント
- Six Sigma = a management method for improving quality that measures quality with numbers (quantitative data) and uses statistical techniques to hold down the “variation (standard deviation σ)” so that defects become extremely few. Its procedure is DMAIC (Define, Measure, Analyze, Improve, Control). The keywords are “quantify” and “suppress variation.”
- Telling apart the confusing quality-related terms: QC circle = continuous improvement by small groups on the shop floor; TQM = company-wide total quality management; ISO 9001 (QMS) = quality assurance through defined procedures, documents, and records; risk management = predicting future problems and planning countermeasures.
用語