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General approaches to data quality and Internet generated data

General approaches to data quality and Internet generated data. associate professor Karsten Boye Rasmussen kbr@sam.sdu.dk Institute of Marketing and Management University of Southern Denmark Campusvej 55, DK-5230 Odense M, Denmark +45 6550 2115 fax: +45 6593 1766

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General approaches to data quality and Internet generated data

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  1. General approaches to data quality and Internet generated data • associate professor Karsten Boye Rasmussen • kbr@sam.sdu.dk • Institute of Marketing and Management • University of Southern Denmark • Campusvej 55, DK-5230 Odense M, Denmark • +45 6550 2115 fax: +45 6593 1766 • Areas: organization and information technology, business intelligence • 'it, communication and organization' www.itko.dk HandbookLondon 2007 1 kbr

  2. Internet improving data quality • concepts and dimensions of data quality • consequences of having poor data quality! - the intuitive approach • what are you talking about? - empirical approach • what can the system talk about? - the ontological • 'fitness for use' - metadata and the dimension of 'documentality' • categories of data generated on or in relation to the Internet • primary data (being generated for this particular use) and secondary • data response (survey questionnaire S-R) • non-reactive sources: • e-mails, blogs, Internet web-logs (on hits, visits, users, etc.), commercial transaction data • mixing methods • data being: validated, used, and plentiful HandbookLondon 2007 2 kbr

  3. The intuitive approach to data quality • data quality metrics • proportion experiencing problems with data quality • 'that 75% of 599 companies surveyed experienced financial pain from defective data' • 'about 14% of the potential taxes due are not collected' • summarized metric of the financial loss • 'poor data management is costing global businesses more than $1.4 billion per year' • error rates of data fields • about 1-5 per cent • but are they all equal? HandbookLondon 2007 3 kbr

  4. Intuitive dimensions • Some OK dimensions • The intuitive approach certainly lacks method with rigor • A somewhat unsystematic and sporadic description HandbookLondon 2007 4 kbr

  5. The empirical approach to data quality • also in committee work HandbookLondon 2007 5 kbr

  6. The theoretical foundation of data quality • Information System (IS) as a representation • of the Real World system (RW) • The ontological approach (Wand & Wang, 1996) • The data representation and recording (Fox et al., 1994) • The conceptual view (Levitin & Redman, 1995) • The systems approach (Huang et al., 1999:34) • the semantics part of the semiotic approach (Price and Shanks, 2004) HandbookLondon 2007 6 kbr

  7. Three categories of 'deficiencies' • a quite "binary" view HandbookLondon 2007 7 kbr

  8. Media approach to data quality • Syntactic quality is thus how well data corresponds to stored meta-data, which can be exemplified by conformance to contingencies of the database • Semantic quality is how the stored data corresponds to the represented external phenomena • Pragmatic quality is how data is suitable and worthwhile for a given use • ("semiotics", Price and Shanks) HandbookLondon 2007 8 kbr

  9. Fitness for use • The 'proof of the pudding' for data quality is the use of the data • 'All the news that's fit to print' New York Times • semiotic framework with degree of objectivity ranging from the syntactic 'completely objective' to the pragmatic 'completely subjective' • 'fitness for use' is subjectivity • 'The single most significant source of error in data analysis is misapplication of data that would be reasonably accurate in the right context' • Error 40 • The relativity moves the attention from the data to the user HandbookLondon 2007 9 kbr

  10. Use, metadata and documentality • data is description - of reality • description of data - is metadata • DDI 'The Data Documentation Initiative' • The quality measures of validity, reliability, accuracy, precision, bias, representativity, etc. • only available through the documentation of the data • the metadata • high documentality means the dataset is a 'pattern' and 'model' HandbookLondon 2007 10 kbr

  11. Errors in survey data • survey is the "ability to estimate with considerable precision the percentage of a population that has a particular attribute by obtaining data from only a small fraction of the total population" (Dillman, 2007) HandbookLondon 2007 11 kbr

  12. Internet & Research • a shift in the medium for data collection • self administered • web surveys • e-mail surveys • e-mail with links • the link points to a web-questionnaire • a mixed-mode within the Internet media • e-mail with attached questionnaire • the questionnaire in software formats (Word of PDF) • e-mail text without attachments or links - answering mail • 3-5 questions • PLUS • completely new type of direct recording of actual behavior in electronic non-reactive data HandbookLondon 2007 12 kbr

  13. Web survey - some problems • uneven accessibility to the Internet • unevenness in regard to the technical abilities • bandwidth, computing power, and software (web-browsers) • however general web-site competences exist • and telephone ownership is now too widespread • - an other medium needed • no random mail generation HandbookLondon 2007 13 kbr

  14. Web survey - the many pros • some reliable e-mail registers do exist • random selection - but not random generated ;-) • CAxI (Computer assisted telephone interviewing) • more complicated structures possible in the answering • software will enforce consistent rule following • experiments using different sequencing of questions • the use of paradata in web (later) HandbookLondon 2007 14 kbr

  15. Web survey - the respondent • Internet coverage, sampling, and the right respondent • sampling is not secured by a large number of respondents • the problem of self-selection • a systematic bias • have to secure the right - or at least only one respondent on the inquiry • the new problem of a 150 per cent answer rate • log-in procedure with a PIN-code is recommended HandbookLondon 2007 15 kbr

  16. Web survey - success and hazard • quicker turnaround than through the postal or face-to-face questionnaire • raising the data quality by securing timely data • the Internet surveys have a much lower 'marginal cost' • with the Internet and supportive software for web surveys • many more surveys are taking place • maybe too many • respondents tend to be more reluctant to participate in surveys HandbookLondon 2007 16 kbr

  17. Secondary data – a richness of data • The data is ready to use • data is being made available and retrievable • raising the data quality through a higher documentation level • ... a long list ... • for some areas the complete data is available • as the data in the operational system of the company • who bought what when and where? • the electronic traces left by the behavior HandbookLondon 2007 17 kbr

  18. Types of online behavior / traces • Investigating the sources • actual e-mails • e-mail fields: sender, date, subject, response - a network • blogs • the web-sites themselves • all these have ethical as well as legal implications (Allen) • Research into the virtual • Logs of behavior • web-log • paradata • ISP-log HandbookLondon 2007 18 kbr

  19. Web-log analysis • hits, pages, visits, users of a web-site • cookies and explicit user log-in • 'click-stream analysis' CLF • pages where the session stops? • patterns of web-movements that explain the stops • going in circles on a web site? • behavior from non-buyers and buyers HandbookLondon 2007 19 kbr

  20. Paradata in surveys • web-log of the process of answering a web survey • timing of the respondent's progression in shifting the web page • paradata is data about the process of data collection (Couper) • collection at the client-side (Heerwegh) • JavaScript can trace with timing different types of answering mechanisms: drop-down lists, radio-buttons, click-items, give value etc. • and client-side can also track how the respondent has changed the answers HandbookLondon 2007 20 kbr

  21. Analyzing virtual communities • Amazon first among communities of costumers • making customer comments and evaluations available to other customers • many more sites of communities are being added • blogs are kind-of • research in the dating sites • potential in personal links as in Linkedin.com • or the links contained in the web itself • and in the constructed virtual reality of 'Second Life' • or other "games" HandbookLondon 2007 21 kbr

  22. Mixed modes and mixed methods • modes of surveys with questionnaires • postal, with interviewer, face-to-face or telephone, or web-mode • mixed-mode has the ability to reduce non-response • 'sequential mixed-mode ... do not pose any problems' (de Leeuw) • but different modes often produce different results (Dillman) • the 'unimode design' • later a mode-specific design taking full advantage of the mode • 'mixed methods' more the combination of qualitative and quantitative methods - and S-R and non-reactive data HandbookLondon 2007 22 kbr

  23. Conclusion • more data is out there • with high syntactic quality • with high validity by interest from sources • and by data - as traces of actual behavior HandbookLondon 2007 23 kbr

  24. ? • Thanks • Karsten Boye Rasmussen • SDU HandbookLondon 2007 24 kbr

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