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Random Variation Vs Trends

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Understanding variation is key to interpret the value stream behavior.  Not all variation is the same. Variation These are some factors which may add variation to the process of cooking a turkey.  Every process has variation. Some causes of variation may be identified and acted upon. We can use two metrics for variation which complement each other: Manual Dice Throwing This simple exercise can help to experience process variation and understand the difference between a process change and inherent process variation. This understanding is key on management decisions to avoid both overreaction and lack of reaction. To run the exercise with actual dice print the form: Exercise: You will need a printed form and 4 dice for each team Throw 4 dice and add the outcomes Record the result in the Run Chart Repeat 50 times Join the dots in the Run Chart with a line Build the Histogram by counting the total number of dots on each group of 3 values Run this Exercise with a Simulator Download this Ex

Virtual Obeya Room

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The Obeya room is a "war room" used by process improvement teams to meet and solve critical multi functional problems.  The room walls are lined up with boards, highly visual charts and graphs showing program timing, milestones and progress to date and countermeasures to existing timing or technical problems.  The team meets in this room regularly but team members can also visit the room, which is fully dedicated to the project, throughout the day. What is an Obeya? Obeya Room Benefits Remove organizational barriers Visual management by displaying all relevant data required in the improvement project Encourage a collaborative environment through regular meetings Implement quicker, more effective solutions The whole team knows what is going on in real time Some Practical Constraints in the Implementation Some companies can't afford the luxury of a fully dedicated room Some of the team members may be located far away so they will only attend the meetings The data displayed

Autocorrelation: How to Manage it

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When a process variable has only random variation, each output is independent of the previous ones.This is what happens in a lottery. In some processes this independence does not happen.   If we control our daily weight, for instance, our weight today is correlated to the weight of the previous days: it has autocorrelation . Weight Autocorrelation One common case of autocorrelation is shown by our body weight.  Our weight today is correlated with: Yesterday's weight:      53% The day before:           39%    Body weight has inertia: you don't expect sudden changes. A similar effect happens when you control a heavy aircraft or a ship: its masive weight prevents you from making a sharp turning or make a sudden stop.  This opposing force to change is what is called Inertia . This inertia definition applies to moving objects and it is proportional to the object mass.  Inertia also applies to fluids: a tank accumulating a fluid will also have this inertia effect. If we try to con