The Traditional Yield is taken at the final step of a process to measure the effectiveness of the overall process.  Specifically, it shows you the percentage of products  or information that are acceptable at the end of a process.  This can be calculated by dividing the final output quantity by the initial input amount and converting that calculation into a decimal or a percentage.  This type of measurement does not take into account scrap, rework or any other inefficiencies in a process it only looks at what goes in and what comes out.  With this in mind yield may be a good initial measurement to start with but keep in mind that it does not reveal the hidden factory.

  DMADV is the methodology used when designing new processes that did not exist prior to their design.  

  ​A function check or functional test will help you measure the ability of your equipment to perform and work as it is intended to or should.

  A changeover is the work required to change a specific machine, resource, work center or line from making the last good piece of an item to making the first good piece of another item.  That means that if the first good piece after the changeover is not good the changeover is not complete.  

This is the core equation used in six sigma.