Precision (DONE) Flashcards
Describe what is meant by precision and what it tells us about random errors.
What is precision of a group of measurements?
Precision of a group of measurements is how tightly spread around a mean value the measurements are. Measurements that are more precise will have a smaller range.
How can we tell if a group of measurements are precise what are the indications? (2)
Measurements are more precise if they are tightly spread around the mean and we can check if they are more precise because they will have a smaller range than measurements that are less precise.
Which results are more precise group A or group B? And why?
Group A
Mean 45
Range 43-47
Group B
Mean 45
Range 44-46
Group B’s results are more precise than group A’s because their results are more tightly spread around the mean and we know this as the range is smaller.
Greater precision means fewer random errors. Group B made fever random errors than group A.
What do greater precise measurements indicate?
Greater precise measurements indicate that fewer random errors were made and this only.
(it has nothing to do with accuracy and if the measurements are closer to their true value.)
