The student`s value is less than the lowest actual value for a given measurement. For example, as we know, the actual value of the mass of an iron cube is 7.90 g. They weigh the same iron cube and discover that it has a mass of 7.90 g. The real value and the value are the same, so we can say that we have determined exactly the mass of the iron cube. Accuracy indicates how close a measurement is to the appropriate value for that measurement. The accuracy of a measurement system is related to the close adequacy between repeated measurements (repeated under the same conditions). Measurements can be precise and precise, accurate, but not precise, precise, but not precise or neither. The term accuracy (or variance) refers to the degree of compliance for a series of measurements. Bias refers to the tendency of measurements to systematically move towards real value and are therefore often referred to as systematic errors. Such errors are often caused by poorly calibrated instruments. On the other hand, random errors are generated by the statistical fluctuations observed when measuring a size. These lead to a dispersion of the observed measurements around a central value. A number of measurements can be described as accurate if the range is very small, that is, the area close to 0 A is described as inaccurate if the range is wide, that is, the area is not close to 0.

The reproducibility of a measurement is called precision. . . .