In the world of Quality, when applying the DMAIC Methodology, at which phase we collect data (Y's) ? :Define - Measure - Analyze - Improve - Control

The Measure phase of six sigma is where we commence to collect the data around our six sigma project. The measure phase starts with identifying the CTQ characteristic which the project intends to improve and subsequently we work and set up a data collection plan. Setup of data collection strategy/plan is done to essentially ensure that all project team members are on common ground about the Y metric of the project.

Data Collection Plan intends to provide clarity around the metrics to be measured, the performance standards for the project Y (as per the goal statement of Project), defining the Upper specification Limit and the Lower Specification Limit for the Y metric and clearly articulating the defect definition for the project Y metric. Also we must articulate how we intend to capture the Y metric data and document the formula to be used, equipment to be used, database or container where the Y metric is to be stored for project use, the information on the data items that we shall need (as per our formula). In certain cases you may even need to document a training plan for data collection team.

Agree with answer given by Mr.Gourab Mitra.

In DMAIC Method of Quality Control, collection of data is done in the "Control" Phase. "Define" is done in Quality Planning stage. "Measure", "Analyse", "Improve" are done in the Execution / Production Phase as part of QC.

  Thank you ,,, While the DMAIC methodology presented may appear linear and explicitly defined, it should be noted that an iterative approach may be necessary – especially for Black Belts and Green Belts that are new to the tools and techniques that make up DMAIC. For instance, you may find that upon analyzing your data (Analyze phase) you did not gather enough data to isolate the root cause of the problem. At this point, you may iterate back to the Measure phase. In addition, prior knowledge of the tools and techniques is necessary in determining which tools are useful in each phase. Remember, the appropriate application of tools becomes more critical for effectiveness than correctness, and you don’t need to use all the tools all the time

Thanks for the invitation

Well......good question

Agreed totally with the excellent description given by Mr, : .Gourab Mitra

I agree with the elegant answers of Mr. gourab 

Thanks for the invitation and for your good question.

Also, thanks for Mr. Gourab Mitra who has given us a detailed explanation about the Data Collection Plan in the Measure phase.

Regards for all!

I agree with  answer of Mr. Gourab Mitra

In MEASURE phase.

In the DMAIC Methodology, data is collected In the Measure phase.

Nice detailed explanation by Gourab Miitra

In the DMAIC Methodology, we collect data In the measure phase.