Difference between accuracy and precision??

Question

Scientifically of course

Answer 1

Think of it similar to playing darts.

If a person is accurate and precise, they'll hit a bulls-eye every time.

If a person is accurate, but NOT precise, they will have 3 darts all around the bulls-eye, but not together.

If a person is precise but not accurate, they will have all 3 darts near each other somewhat clustered.

See the chart below

http://www.onlyguidance.com/img/accuracy...

Answer 2

I don't know about scietifically, but an example is with clocks. If you have a digital clock that shows hours and minutes the time will change once per minute. If it is on time, you could say it is accurate. However, if you wanted to know seconds you'd be out of luck because it isn't that precise. Whereas, an analogue clock the minute hand continually moves. even though it would be difficult to tell the seconds, it would be considered precise. It may or may not be accurate depending on wheather it is set on the correct time.

Answer 3

accuracy is the closeness of your measurements to being CORRECT or the accepted value of quantity measured.

Precision is the CLOSENESS of a set of measurements of same quantity made in the same way

EXAMPLE:

The density of water=1

If you perform an experiment  five times to test the density of water and you come up with .98, .99, .99, 1.00 and .97 you are both accurate and precise because your measurements are close (precise) and you are accurate because you are close to the accecpted value (that water's density=1)