Precision means the close agreement between two or more measurements of the same amount. It is expressed as the difference between the measured value and the average. Accuracy indicates the degree of conformity of the values measured between them. Precision refers to the agreement between a measurement and the actual or correct value. When a clock strikes twelve o`clock, when the sun is just above the head, the clock is designated as accurate. The measurement of the clock (twelve) and the phenomena it must measure (The Sun on the demodenite) corresponds. Accuracy cannot be discussed judiciously, unless the actual value is known or known. (Note: the actual value of a measurement can never be known.) The accuracy of a measurement system refers to the proximity of the concordance between repeated measurements (repeated under the same conditions). However, it is very easy to imagine that you could be sure that the desk was no more than ten centimeters (five inches) different from your measurement.
Perhaps you have experience with tape measurements. And based on this experience, you`re sure your meter couldn`t be stretched five inches from its correct length. If you don`t have that confidence, maybe ten inches or a foot would make you confident. After the measurement, you could say, “This office does not exceed 1.35 m and is not less than 0.95 m.” You could make that statement with confidence. The scientist would write L – 1.20 ± 0.15 m. The format is “value more or less uncertainty.” To calculate the percentage error for measuring aluminum density, we can replace the indicated values of 2.45 g/cm3 with the experimental value and 2.70 g/cm3 with the assumed value. “The smaller the difference between the measured value of repeated measurements of the same amount, the greater the accuracy.” If the experimental value is less than the accepted value, the error is negative. If the experimental value is greater than the accepted value, the error is positive.
Often, an error is reported as the absolute value of the difference, in order to avoid confusion of a negative error. The percentage error is the absolute value of the error divided by the accepted value and multiplied by 100%. Text error [latex], error, |, text, experimental value, “text” and “accepted value” | Precision means the proximity of an experimental value or the average of a set of measurements at the actual value. It is a measure of the difference between the average and the actual value. Precision expresses the accuracy of the measurement. The “value ± 1 SD” format means that if you repeat the measurement, 68% of the time your new measurement falls in that interval. “The smaller the difference between the measured value of repeated measurements of the same amount, the greater the accuracy.” To calculate the error percentage for measuring aluminum density, we can replace the indicated values of 2.45 g/cm3 with the experimental value and 2.70 g/cm3 with the assumed value. The accepted value is a number or value that scientists and the public consider to be true. An individual measurement may be accurate or imprecise depending on the exact value approach.
Suppose you are doing an experiment to determine the density of an aluminum sample. The accepted value of a measurement is the true or correct value based on a general agreement with a reliable reference.