Beyond Zero and One (Andrew Smart) / quote 76 of 171
Accuracy versus precision
is important to keep in mind the difference between accuracy and precision. Accuracy refers to how close a measurement is to its true value; precision refers to the repeatability of the measurement. If you have a bias in your measuring equipment, you might be very precise (i.e., get the same result every time) but inaccurate (i.e., you are not measuring the true value). Think of a faulty blood-glucose