Validating sampling plans
Examples of raw data collection include: on tags, in log books, entered into data bases, scribbled on surveys, interpreted from phone conversations or automatically tallied by machinery.2. The answer to this question is typically a front line employee: operator, clerk, waiter or other. Combined with family of measure (Fo M), the answers can be used to create a handy reference sheet. Every team compares “after-data” to “before-data” to validate process improvements.
Armed with summary statistics, graphical displays of central tendency, variability, skewness, graphical displays of time, and a little knowledge of research methods (control groups and randomness), the project team can choose appropriate comparative experiments to validate future process improvements.A project team needs useful decision trees, additional software skills and a capable mentor (Black Belt, statistician or Master Black Belt) to help guide the team to create a valid process improvement validation strategy using comparative experiments, due diligence and good research methods.This section of the DMP only includes one question.If the data is collected occasionally (less often than weekly), the team will have to think about more frequent data collection or face an extended project cycle time.If there is lots of data, collected frequently (at least weekly) for a long period of time, a trend analysis should be conducted to see if the team can consider the data “historical.” If the data is historical – perhaps several quarters’ worth – then the team can validate its process improvements faster with less effort (smaller sample size requirements for the comparative experiment).A data management plan (DMP), which outlines the use of data, can be employed as a key document in the Measure phase of DMAIC.Because of its rigor, its identification of process validation (Control) and its stratification factors (Analysis), a DMP can be one of the pivotal planning documents for a Six Sigma project.The before-data usually consists of one of three levels – no data, occasional data or lots of data.If the data does not exist, this is a potential project killer or could at least extend project cycle time significantly because the team will have to define, collect and validate its own data.Every main project metric should be at least displayed on an individual chart or median chart since both can handle counts and measures. What is the main purpose of the process improvement team?There are essentially four ways to improve a process.