Data Quality under the Computer Science perspective

Monica Scannapieco Universita’ di Roma, “la Sapienza”, Rome, Italy IASI-CNR, Rome, Italy

monscan@dis.uniroma1.it
Tiziana Catarci Universita’ di Roma, “la Sapienza”, Rome, Italy

catarci@dis.uniroma1.it

Abstract: La qualità dei dati è una tematica affrontata in ambito statistico, gestionale, informatico, insieme a molti altri settori scientifici. Il presente articolo considera il problema della definizione della qualità dei dati dal punto di vista informatico. Sono comparate alcune proposte di dimensioni (o caratteristiche) che contribuiscono alla definizione della qualità dei dati e viene introdotta una definizione “base” di tale concetto. E’ inoltre illustrata una …ver más…

Generally speaking, data quality can be related to a set of “dimensions” that are usually defined as quality properties or characteristics. Examples of dimensions are accuracy, completeness and consistency. An intuitive understanding of such dimensions is suggested by the following examples; they refer to a record Citizen, with fields Name, Sex and Email, shown in Figure 1.
CITIZEN Name Sex Email

Figure 1: Example record.

If Name has a value Mke, while Mike is the correct value according to a dictionary of English names, this is a case of low accuracy. An example of low completeness is provided by considering Email; a null value for Email may have different meanings, that is (i) the specific citizen has no e-mail address, and therefore the field is inapplicable (this case has no impact on completeness), or (ii) the specific citizen has an e-mail address which has not been stored (in this case the degree of completeness is low). As an example of consistency, let us consider the values of the fields Name and Sex. If Name has a value that is John and the value of Sex is Female, this may be a case of low consistency. It is worth noting that: In the literature, there is no agreement on the set of the dimensions characterizing data

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quality. Many proposals have been made, but no one has emerged above the others and has established itself as a standard. Even if some dimensions are universally considered