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What is accuracy?

Last updated date: 17th Jul 2024
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Hint: The closeness of a calculated value to a norm or known value is referred to as accuracy. For example, if the measurements for a given material are similar to the known value on average, but the measurements are far apart, you have accuracy without precision.

Complete answer:
The accuracy of a single measurement is referred to as its precision. The measurement's accuracy is measured by comparing it to the accurate or agreed value. An precise calculation, like touching the middle of a bullseye, is similar to the true value.
In contrast, precision measures how much a sequence of variables agree with one another, regardless of whether any of them are similar to the true value. Calibration is often used to change precision, resulting in values that are both correct and exact.
Scientists also report a measurement's percent error, which communicates how far a calculated value is from the true value.
For example, if you weigh a cube that is known to be 10.0 cm across and get 9.0 cm, 8.8 cm, and 11.2 cm, these values are more reliable than if you got 11.5 cm, 11.6 cm, and 11.6 cm (which are more precise).
In other words, consistency indicates how similar a value is to a norm. An ideal is a norm that is widely accepted. A chemist can create a standard solution to serve as a guide. There are also units of measuring norms, such as the metre, litre, and kilogramme. The atomic clock is a kind of standard that is used to evaluate the precision of time measurements.

With a more precise instrument (measurements are taken in finer increments) and greater repeatability or reproducibility, the random error would be reduced (precision). Consider a popular laboratory experiment in which you would calculate the percentage of acid in a vinegar sample by observing the amount of sodium hydroxide solution needed to neutralise a given volume of vinegar. You do the experiment and calculate the result. To be safe, you repeat the process on a second equivalent sample from the same bottle of vinegar. If you've done this in the lab before, you'll know that the second experiment is very unlikely to produce the same results as the first.