Monitoring the Project Six Sigma Simplicity Continuous Improvement - Monitoring

Key Learning Points GB certification standard Primary Metric Graph using standard template showing Charter goal was met Demonstrate how the y and the x's are being ‘monitored’ Continuous Improvement - Monitoring

Check the improvements work Did you meet your goal in the charter? Surprisingly without DMAIC many people think that they have completed a successful project just because they have spent time on it. If you have not met your promises on your charter agreed in the Opportunity stage [Define], figure out what has gone wrong

Comparing with a target? Objective Is team successful? Yes or No 11 No 7 5 4 3 2 Yes Graph is a control chart of the primary metric after you have implemented changes. In this example the higher the process the better Fill in the table yourself Continuous Improvement - Monitoring

Comparing an average with a target? For this example sales on average is 5M$, standard deviation = 0.8 Next month you would expect the sales be above 5M$ 50% of the time and below 5M$ 50% of the time So the average will go up 50% of the time and down 50% of the time Will the new average be above the goal?

Comparing with a target? Distance Average Beyond Target Sample size required 1 standard deviation 10 2 standard deviations 5 3 standard deviations 3 A control chart tells us whether the remaining variation is due to common or special causes. What we want is for the process to be in control, stable, predictable We can use this table when we are unsure. If the process is in control and you use this table 95% of the time in the future your process will average above the target Distance Control Limits below Target Sample size required s 10 2s 5 3s 3

How sure are we of the metric ? Distance Average Beyond Target Sample size required 1 standard deviation 10 2 standard deviations 5 3 standard deviations 3 Table based on same confidence intervals as in Quantify and Verify Causes section. It works for normal data. For more information consult a text book or black belt on 1 Sample T-Tests. Here with 10 data points we can be sure that the process average in future will be at least 5. (s = 1.3. Observed average – s = 5. ) If our goal was at least 5 or less we have succeeded! Continuous Improvement - Monitoring

Exercises Project target is 90, you have achieved average 94 standard deviation 2. How many readings with the same average and standard deviation do you need to close the project? Distance Average Beyond Target Sample size required 1 standard deviation 10 2 standard deviations 5 3 standard deviations 3 Continuous Improvement - Monitoring

Exercises Project aim is to draw an average of 24 drawings a month. Current standard deviation is 3 How many months will the project take if you measure each month? Distance Average Beyond Target Sample size required 1 standard deviation 10 2 standard deviations 5 3 standard deviations 3 Continuous Improvement - Monitoring

Control Methods BEST Eliminate the variable: Eliminate it by understanding variable interactions or by mistake proofing. Automate the variable: Implement automated controls that require little or no operator intervention. SPC on the Xs: Implement statistical process control on the input variable (or X) that controls Y. This form of SPC requires that Y = f (X) be understood. SPC on the Ys: Implement statistical process control on the output variable or Y. This form of SPC is most frequently used by industry. S.O.P.: This is the standard operating procedure implemented to detect defects. The action is not sustainable short term or long term. WORST REMEMBER OUR CONTROL LEVELS---Based on statistical principles, control charts allow for the identification of unnatural (non-random) patterns in process variables. When the control chart signals a non-random pattern, we know that special cause variation has changed the process. The actions we take to attack non-random patterns in control charts are the key to successful SPC usage. Control limits are based on establishing +/- 3 sigma limits for the Ys or Xs being measured.(mu+-3 * Std. Dev) Continuous Improvement - Monitoring

Monitoring Control Methods Eliminate the variable: List what has been disposed. Automate the variable: Inspect output Monitor whether the automation is used Standard Operating Procedure: Document. Regular audit. Training with assessment. Accountability SPC on X’s and Y’s Identify metric, control limits, and specifications Continuous Improvement - Monitoring

Monitoring Continuous Improvement - Monitoring

Summary We check that after our improvements X and Y have actually changed We check that the process is strong enough for use to rely on it. i.e. - it is in control and we are confident that in future the process lies well above the goal The more we exceed the goal and the smaller the variation the less data we need