Data analysis is a process of inspecting, cleansing, transforming, and modeling data with the goal of discovering useful information, informing conclusions, and supporting decision-making. Data analysis has multiple facets and approaches, encompassing diverse techniques under a variety of names, and is used in different business, science, and social science domains. In today's business world, data analysis plays a role in making decisions more scientific and helping businesses operate more effectively.
Data mining is a particular data analysis technique that focuses on statistical modeling and knowledge discovery for predictive rather than purely descriptive purposes, while business intelligence covers data analysis that relies heavily on aggregation, focusing mainly on business information. In statistical applications, data analysis can be divided into descriptive statistics, exploratory data analysis (EDA), and confirmatory data analysis (CDA). EDA focuses on discovering new features in the data while CDA focuses on confirming or falsifying existing hypotheses. Predictive analytics focuses on the application of statistical models for predictive forecasting or classification, while text analytics applies statistical, linguistic, and structural techniques to extract and classify information from textual sources, a species of unstructured data. All of the above are varieties of data analysis.
Data integration is a precursor to data analysis, and data analysis is closely linked to data visualization and data dissemination.
Guildford (/ˈɡɪlfərd/ (listen)) is a town in west Surrey, around 27 mi (43 km) southwest of central London. As of the 2011 census, the town has a population of about 77,000 and is the seat of the wider Borough of Guildford, which had around 148,998 inhabitants in 2019. The name "Guildford" is thought to derive from a crossing of the River Wey, a tributary of the River Thames that flows through the town centre.
The earliest evidence of human activity in the area is from the Mesolithic and Guildford is mentioned in the will of Alfred the Great from c. 880. The exact location of the main Anglo-Saxon settlement is unclear and the current site of the modern town centre may not have been occupied until the early-11th century. Following the Norman Conquest, a motte-and-bailey castle was constructed, which was developed into a royal residence by Henry III. During the late Middle Ages, Guildford prospered as a result of the wool trade and the town was granted a charter of incorporation by Henry VII in 1488.
The River Wey Navigation between Guildford and the Thames was opened in 1653, facilitating the transport of produce, building materials and manufactured items to new markets in London. The arrival of the railways in the 1840s attracted further investment and the town began to grow with the construction of its first new suburb at Charlotteville in the 1860s. The town became the centre of a new Anglican diocese in 1927 and the foundation stone of the cathedral was laid in 1936. Guildford became a university town in September 1966, when the University of Surrey was established by Royal Charter.
Guildford is surrounded on three sides by the Surrey Hills Area of Outstanding Natural Beauty, which severely limits its potential for expansion to the east, west and south. Recent development has been focused to the north of the town in the direction of Woking. Guildford now officially forms the southwestern tip of the Greater London Built-up Area, as defined by the Office for National Statistics.