Subsequent questions could focus on the quantity and variability of the results to build confidence in the data. Assuming that the experiment has a purpose, it s possible to accept or reject the findings. Statistics become not only a tool for summarization, but for calculating risks. The x factors With responsibility for some manufacturing systems, one should be aware of the various factors that affect the statistics. Some factors are random, while others are controllable.
Controllable factors are inputs.
They can be numerical, such as temperature, or categorical, such as raw material supplier. Not all variables are uncontrollable, some can be controlled and represent regular input to a system. The responses obtained from both types of variables must be measured in some quantifiable manner. Measuring the outputs, or responses, must be done in some quantitative manner such as a 1 to 5 scale. There are variables, such as ambient temperature and humidity, which can t be easily controlled or, in some cases, even identified.