what is the difference between accuracy and precision ??? Give examples..
Answers
Accuracy and precision are used in context of measurement. Accuracy refers to the degree of conformity and correctness of something when compared to a true or absolute value, while precision refers to a state of strict exactness — how consistently something is strictly exact.
In other words, the precision of an experiment, object, or value is a measure of the reliability and consistency. The accuracy of an experiment, object, or value is a measurement of how closely results agree with the true or accepted value.
EXAMPLE
Accurate and precise: If a weather thermometer reads 75oF outside and it really is 75oF, the thermometer is accurate. If the thermometer consistently registers the exact temperature for several days in a row, the thermometer is also precise.
Precise, but not accurate: A refrigerator thermometer is read ten times and registers degrees Celsius as: 39.1, 39.4, 39.1, 39.2, 39.1, 39.2, 39.1, 39.1, 39.4, and 39.1. However, the real temperature inside the refrigerator is 37 degrees C. The thermometer isn’t accurate (it’s almost two degrees off the true value), but as the numbers are all close to 39.2, it is precise.