Dirty data

Dirty data is inaccurate, incomplete or erroneous data, especially in a computer system or database.

In reference to databases, this is data that contain errors. Unclean data can contain such mistakes as spelling or punctuation errors, incorrect data associated with a field, incomplete or outdated data, or even data that has been duplicated in the database. It can be cleaned through a process known as data cleansing.

Other definition: secretive and discrediting data.

Following the definition of Gary T. Marx, Professor Emeritus of MIT, there are 4 types of data.

TABLE 1: Types of Data

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