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Measurement is the process of estimating the magnitude of some attribute of an object, such as its length or weight, relative to some standard (unit of measurement), such as a meter or a kilogram. The term is also used to indicate the number that results from that process. Metrology is the scientific study of measurement. The act of measuring usually involves using a measuring instrument, such as a ruler, weighing scale, thermometer, speedometer, or voltmeter, which is calibrated to compare the measured attribute to a measurement unit. Any kind of attributes can be measured,[1] including physical quantities such as distance, velocity, energy, temperature, or time. The assessment of attitudes or perception in surveys, or the testing of aptitudes of individuals are also considered to be measurements. Indeed, surveys and tests are considered to be "measurement instruments".
Measurements always have errors and therefore uncertainties. In fact, the reduction —not necessarily the elimination— of uncertainty is central to the concept of measurement. Measurement errors are often assumed to be normally distributed about the true value of the measured quantity. Under this assumption, every measurement has three components: the estimate, the margin of error or uncertainty or error bound, and the confidence level — that is the probability that the actual magnitude lies within the margin of error. For example, a measurement of the length of a plank might result in an estimate of 2.53 meters plus or minus 0.01 meter, with a level of confidence of 99%.
The initial state of uncertainty, prior to any observations, is necessary to assess when using statistical methods that rely on prior knowledge (Bayesian methods). This can be done with calibrated probability assessment.
Measurement is fundamental in science; it is one of the things that distinguish science from pseudoscience. It is easy to come up with a theory about nature, hard to come up with a scientific theory that predicts measurements with great accuracy. Measurement is also essential in industry, commerce, engineering, construction, manufacturing, pharmaceutical production, and electronics.
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Allison, which may come from a medieval Norman nickname for Alice, meaning "noble", or from the Irish name "Iseult", meaning "fair lady".
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Anglicized form of the Latin given name Justinus, a derivative of Justus. Justinus was the name borne by various early saints, notably a 2nd-century Christian apologist and a (possibly spurious) boy martyr of the 3rd century. As an English name, Justin has enjoyed considerable popularity in the second part of the 20th century.
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Jordan, officially the Hashemite Kingdom of Jordan, (Arabic: الأردنّ al-Urdunn) is a country in Southwest Asia spanning the southern part of the Syrian Desert down to the Gulf of Aqaba. It shares borders with Syria to the north, Iraq to the north-east, Israel and the disputed Palestinian territories to the west, and Saudi Arabia to the east and south. It shares control of the Dead Sea with Israel, and the coastline of the Gulf of Aqaba with Israel, Saudi Arabia and Egypt. Much of Jordan is covered by desert land, particularly the Arabian Desert, however the north-western area, with the sacred Jordan River is regarded as part of the Fertile Crescent.
The capital city, Amman, is in the north-west. Jordan has a rich history, its location in the central Middle East has long made it a prized possession. During its long history, Jordan has seen numerous civilisations, including such ancient eastern civilisations as the Sumerian, Akkadian, Israelite, Babylonian, Assyrian, Mesopotamian and Persian empires. Jordan was for a time part of Pharaonic Egypt and spawned the native Nabatean civilisation who left rich archaeological remains at Petra. Cultures from the west also left their mark such as the Macedonian, Roman and Byzantine empires. Since the seventh century the area has been under Muslim and Arab cultures, with the exception of a brief period under British rule.
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