Showing posts with label Variation. Show all posts
Showing posts with label Variation. Show all posts

Monday, July 28, 2014

Sources of Variation

Sources of variation can be categorized into two major categories. These are called common cause variation and special cause variation.
Common Cause Variation:
·        Present all the times in the process
·        Individually will have a minor effect
·        Collectively the variation can be added up leading to significant effect
Special Cause Variation:
·        Not always present in the process
·        Appear sporadically
·        Come from outside the process
·        Can have large or small affect on variation but typically have major impact

Strategy to address special cause:
·        Gather the data real time to signal the special causes quickly
·        Take immediate actions to reduce the damage
·        Investigate for the cause – Understand what is different
·        Plan for a long term solution
Strategies to address the common causes involves
·        Stratify – Identify the patterns in the way the data is clustered or do not clustered
·        Experiment – Make planned changes and learn from the effect
·        Disaggregate – Break the processes into small pieces and manage the pieces effectively

7 Step method of process improvement:
1.      Purpose
·         What are we trying to do?
·        What problem/gap is being addressed?
·        What is the impact?
·        What are the other reasons to fix this gap?
·        How to know things are better once improved?
·        What is your plan for this project?
2.      Current Situation
·        What is the history?
·        What are the symptoms of the problem?
·        Where do they appear?
·        What happens when the problem occurs?
·        Who is involved?
·        Can we draw the flowchart to depict the process?
3.      Cause Analysis
·        What are the causes for the symptoms?
·        Which can be verified using data?
·        What are the potential root causes?
4.      Solutions
·        What actions will address the root causes?
·        What criteria can be used to compare the solutions?
·        What are the pros and cons of each solution?
·        Which is the best? Which one will be selected?
·        How to test in a small scale? How to verify with data?
·        Which solution proved to be more effective?
·        What are the plans for full scale implementation?
5.      Results
·        How will the results meet the targets?
·        How well the plan executed?
·        How the results can be sustained in future?
6.      Standardization
·        What is the new standard method?
·        How will the users be trained?
·        What is in place to ensure the results are maintained?
·        How the results will be monitored?
·        What means are in place to foster ongoing improvements?
7.      Future plans
·        What is not addressed by this project?
·        What are the recommendations?
·        What is being learned from the project?
·        How the documentation will be finished?
·        What is the exit criterion to close the project?
·        Did we meet the exit criteria?