Yes, six sigma can be applied everywhere as you want.
A baseball coach can use six sigma to evaluate the performance of each player and find out why in some cases some players make mistakes but others are excellent.
By narrowing down all the inputs and analysing them, coaches are able to control when is the best time to send specified player to play. Of cause, we need stastistic data and tools to support.
Furthermore, DOE is such an advanced tool to get the best pose or positions for a single baseball player to play, either to throw the ball or strike the ball.
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