Curious Cat Management Improvement Connections

Tag: mistake proofing

Practical Combinatorial Testing by Raghu Kacker, Rick Kuhn, Yu Lei
"Combinatorial methods can help reduce the cost and increase the effectiveness of software testing for many applications. ... With the NASA application, for example, 67% of the failures were triggered by only a single parameter value, 93% by 2-way combinations, and 98% by 3-way combinations. The detection rate curves for the other applications studied are similar, reaching 100% detection with 4 to 6 way interactions."

Maximize Test Coverage Efficiency And Minimize the Number of Tests Needed by John Hunter
"The steeper the slope the more efficient your test plan is. If you repeat the same tests of pairs and triples andâ€¦ while not taking advantage of the chance to test, untested pairs and triples you will have to create and run far more test than if you intelligently create a test plan. With many interactions to test it is far too complex to manually derive an intelligent test plan. A

Each necessary, but only jointly sufficient by John Allspaw
"for complex systems: there is no root cause. ... Frankly, I think that this tendency to look for singular root causes also comes from how deeply entrenched modern science and engineering is with the tenets of reductionism. So I blame Newton and Descartes. ... In the same way that you shouldnâ€™t ever have root cause 'human error', if you only have a single root cause, you havenâ€™t dug deep enough."

Using Poka-Yoke Techniques for Early Defect Detection
"Poka-yoke devices fall into two major categories: prevention and detection. A prevention device engineers the process so that it is impossible to make a mistake at all. A classic example of a prevention device is the design of a 3.5 inch computer diskette.The diskette is carefully engineered to be slightly asymmetrical so that it will not fit into the disk drive in any orientation other than the correct one. Prevention devices remove the need to correct a mistake, since the user cannot make the mistake in the first place. A detection device signals the user when a mistake has been made, so that the user can quickly correct the problem. The small dish used at the Yamada Electric plant was a detection device; it alerted the worker when a spring had been forgotten. Detection devices typically warn the user of a problem, but they do not enforce the correction. ... [in software tesging] Unit testing and "smoke testing" [7] come closer to the notion of poka-yoke, in that they are located close to the source of the potential mistakes and the quick feedback they provide can keep mistakes from moving further along in the process."

Training Within Industry
Blog on standardization, process improvement, training and lean manufacturing topics.

Curious Cat Management Improvement Connections by John Hunter
The aim of Curious Cat Management Improvement Connections is to contribute to the successful adoption of management improvement to advance joy in work and joy in life. The site provides connections to resources on a wide variety of management topics to help managers improve the performance of their organization. The site was started in 1996 by John Hunter.