Difference between accuracy and precision
accuracy vs precision :
These two terms used in the fields of science, engineering and statistics are very closely related yet not quite the same. Accuracy can be explained as the closest value to the actual and true measurement of a substance. Precision on the other hand can be explained as the consistency of the results over the same instance or the object. It is also called the reproducibility or repeatability which means that further measurements or calculations done on the same substance should give out the same or extremely close results.
For example, if in reality the temperature in a room is 28 F and the temperature sensor reads 28 F, then the temperature sensor can be named as accurate. But if on several occasions, the temperature sensor matches the actual temperature but it varies slightly from time to time as 28.19 F, 27.99 F, 28.2 F, 28.8 F, then the reading 27.99 F could be named as being more precise than all the other readings obtained from the temperature sensor.
The terms accuracy and precision cross paths every so often. If in a game of darts, a man hits the center of the target, then he is deemed as accurate. But if he hits the center of the target repeatedly for a number of times, he is deemed as both accurate and precise. Also, a measurement system or a computational method is considered as valid and true if it is both precise and accurate. And if in reality, the temperature of a room is 28 F and the temperature sensor reads 28 F, 28 F, 27.99 F, 28 F, 27.98 F repeatedly, that temperature sensor is both precise and accurate and therefore, can be deemed as reliable.
It is important for a good meteorological instrument to have a high accuracy and high precision to be accepted as reliable. Yet it is difficult for an ordinary person to be accurate in day to day life. A person who is less than 6 feet tall would not state his height as 5 feet 11 inches and half an inch as it would be difficult and complex for another ordinary person to understand. Yet, he could have used millimeters to state his height accurately but still, he would undergo difficulties of making another person understand his actual height. Being accurate in day to day life thus proves to be impractical.