The world is awash with data.. With mobile devices and internet connections, data capture is simple and powerful computers make the analysis of “big data” feasible. But there are challenges: many data sets are too large and too complex to be analysed or understood using traditional data-processing methods. Our current armoury of analysis techniques is inadequate and new mathematical methods are needed.
Globally, something like five exabytes of data are created every day. That is about a million million million words. The data comes from a multitude of sources. Among these are internet traffic, phone calls, education, medical and health records, court reports, genome sequences, astrophysical observations, stock-market movements and social networks. On Twitter about 6,000 tweets are sent every second, which means 500 million per day and about 200 billion per year.
Into the matrix
Small data sets can be organised into a matrix using a simple spreadsheet. For big data, processing is beyond human capacity and more sophisticated methods are required: new, more efficient forms of processing are needed to extract value from the data. Big data presents huge management tasks: data capture, verification, storage, sorting, analysis, visualisation and presentation.
Big data is noisy, unstructured and ever-changing. Real-time analysis requires hugely parallel processing with software running simultaneously on thousands of processors. Brute-force analysis alone is ineffective, and modern computer architectures require innovative algorithms to exploit their power. Specialised software tools are available, such as Hadoop, a software framework for distributed storage and processing of very large data sets on computer clusters, and Presto, a system developed by Facebook for running interactive analytic queries.
Unlocking the information from large data sets yields understanding and enables predictions about future trends. Big data analysis can reveal new links and relationships. Large companies – eBay, Amazon, Netflix, Facebook and Google – are engaged in analysis of customer preferences: patterns of purchases enable them to recommend products that a customer is likely to buy. Other applications include insurance-fraud detection, flight analysis and medical diagnosis and prognosis.
Humans are poor at heavy quantitative analysis but brilliant at pattern recognition. For example, we might be able to recall a face seen briefly years ago. So far, machines cannot match us but, as large data analysis progresses and new techniques are developed, substantial advances can be expected. Millions of images can be input to deep-learning algorithms to train them to recognise patterns.
Many human activities are organised in networks, which can be modelled using graph theory. A graph is just a collection of nodes linked by edges, like an electric- circuit diagram or a railway map. The branch of mathematics that deals with connectivity and continuity is called topology, and it includes graph theory. Topological data analysis provides a way of generating structured data sets from unstructured, chaotic data. The structured data can then be processed using algorithms.
Often, data is represented by points in a high-dimensional space – difficult to visualise but amenable to algebraic manipulation. Large multidimensional data sets can be reduced to a greatly compressed state using methods such as singular value decomposition, where the essential information-bearing components are isolated and the rest dumped.
There is an acute shortage of experts in data analysis in many industrial sectors, including health, finance, climate science, pharmaceuticals and online services. Several universities, UCD included, offer postgraduate programmes in data analytics. With so many open problems, this is a promising field for young people.
This article was originally published on www.irishtimes.com and can be viewed in full
Archive
- October 2024(44)
- September 2024(94)
- August 2024(100)
- July 2024(99)
- June 2024(126)
- May 2024(155)
- April 2024(123)
- March 2024(112)
- February 2024(109)
- January 2024(95)
- December 2023(56)
- November 2023(86)
- October 2023(97)
- September 2023(89)
- August 2023(101)
- July 2023(104)
- June 2023(113)
- May 2023(103)
- April 2023(93)
- March 2023(129)
- February 2023(77)
- January 2023(91)
- December 2022(90)
- November 2022(125)
- October 2022(117)
- September 2022(137)
- August 2022(119)
- July 2022(99)
- June 2022(128)
- May 2022(112)
- April 2022(108)
- March 2022(121)
- February 2022(93)
- January 2022(110)
- December 2021(92)
- November 2021(107)
- October 2021(101)
- September 2021(81)
- August 2021(74)
- July 2021(78)
- June 2021(92)
- May 2021(67)
- April 2021(79)
- March 2021(79)
- February 2021(58)
- January 2021(55)
- December 2020(56)
- November 2020(59)
- October 2020(78)
- September 2020(72)
- August 2020(64)
- July 2020(71)
- June 2020(74)
- May 2020(50)
- April 2020(71)
- March 2020(71)
- February 2020(58)
- January 2020(62)
- December 2019(57)
- November 2019(64)
- October 2019(25)
- September 2019(24)
- August 2019(14)
- July 2019(23)
- June 2019(54)
- May 2019(82)
- April 2019(76)
- March 2019(71)
- February 2019(67)
- January 2019(75)
- December 2018(44)
- November 2018(47)
- October 2018(74)
- September 2018(54)
- August 2018(61)
- July 2018(72)
- June 2018(62)
- May 2018(62)
- April 2018(73)
- March 2018(76)
- February 2018(8)
- January 2018(7)
- December 2017(6)
- November 2017(8)
- October 2017(3)
- September 2017(4)
- August 2017(4)
- July 2017(2)
- June 2017(5)
- May 2017(6)
- April 2017(11)
- March 2017(8)
- February 2017(16)
- January 2017(10)
- December 2016(12)
- November 2016(20)
- October 2016(7)
- September 2016(102)
- August 2016(168)
- July 2016(141)
- June 2016(149)
- May 2016(117)
- April 2016(59)
- March 2016(85)
- February 2016(153)
- December 2015(150)