Data
Data (/ˈdeɪtə/ DAY-tə, US also /ˈdætə/ DAT-ə) are a collection of discrete or continuous values that convey information, describing the quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted formally. A datum is an individual value in a collection of data. Data are usually organized into structures such as tables that provide additional context and meaning, and may themselves be used as data in larger structures. Data may be used as variables in a computational process.[1][2] Data may represent abstract ideas or concrete measurements.[3] Data are commonly used in scientific research, economics, and virtually every other form of human organizational activity. Examples of data sets include price indices (such as the consumer price index), unemployment rates, literacy rates, and census data. In this context, data represent the raw facts and figures from which useful information can be extracted.
Data are collected using techniques such as measurement, observation, query, or analysis, and are typically represented as numbers or characters that may be further processed. Field data are data that are collected in an uncontrolled, in-situ environment. Experimental data are data that are generated in the course of a controlled scientific experiment. Data are analyzed using techniques such as calculation, reasoning, discussion, presentation, visualization, or other forms of post-analysis. Prior to analysis, raw data (or unprocessed data) is typically cleaned: Outliers are removed, and obvious instrument or data entry errors are corrected.
Data can be seen as the smallest units of factual information that can be used as a basis for calculation, reasoning, or discussion. Data can range from abstract ideas to concrete measurements, including, but not limited to, statistics. Thematically connected data presented in some relevant context can be viewed as information. Contextually connected pieces of information can then be described as data insights or intelligence. The stock of insights and intelligence that accumulate over time resulting from the synthesis of data into information, can then be described as knowledge. Data has been described as "the new oil of the digital economy".[4][5] Data, as a general concept, refers to the fact that some existing information or knowledge is represented or coded in some form suitable for better usage or processing.
Advances in computing technologies have led to the advent of big data, which usually refers to very large quantities of data, usually at the petabyte scale. Using traditional data analysis methods and computing, working with such large (and growing) datasets is difficult, even impossible. (Theoretically speaking, infinite data would yield infinite information, which would render extracting insights or intelligence impossible.) In response, the relatively new field of data science uses machine learning (and other artificial intelligence) methods that allow for efficient applications of analytic methods to big data.
Lichfield (/ˈlɪtʃfiːld/) is a cathedral city and civil parish[2] in Staffordshire, England. Lichfield is situated roughly 16 mi (26 km) north of Birmingham, 8.1 miles (13.0 km) from Rugeley, 9 miles (14 km) from Walsall, 7.9 miles (12.7 km) from Tamworth and 13 miles (21 km) from Burton Upon Trent. At the time of the 2011 Census the population was estimated at 32,219 and the wider Lichfield District at 100,700.[3]
Notable for its three-spired medieval cathedral, Lichfield was the birthplace of Samuel Johnson, the writer of the first authoritative Dictionary of the English Language. The city's recorded history began when Chad of Mercia arrived to establish his Bishopric in 669 AD and the settlement grew as the ecclesiastical centre of Mercia. In 2009, the Staffordshire Hoard, the largest hoard of Anglo-Saxon gold and silver metalwork, was found 5.9 km (3.7 mi) south-west of Lichfield.
The development of the city was consolidated in the 12th century under Roger de Clinton, who fortified the Cathedral Close and also laid out the town with the ladder-shaped street pattern that survives to this day. Lichfield's heyday was in the 18th century, when it developed into a thriving coaching city. This was a period of great intellectual activity, the city being the home of many famous people including Samuel Johnson, David Garrick, Erasmus Darwin and Anna Seward, and prompted Johnson's remark that Lichfield was "a city of philosophers".
Today, the city still retains its old importance as an ecclesiastical centre, and its industrial and commercial development has been limited. The centre of the city has over 230 listed buildings (including many examples of Georgian architecture), and preserves much of its historic character.