Frequently asked questions.(Software World Intelligence)

From: Software World | Date: May 1, 2004 | Copyright information

What is a missing value?

A missing value, also known as a 'hole' or a 'gap' is an empty field in a database. In database terminology missing values are labelled 'null' values.

Typically what percentage of values are missing from a lifestyle database.

It is difficult to generalise but as much as 30-40% of values can be missing.

What are the implications of missing values on data-driven organisations and marketing campaigns?

Missing values reduce the effective size of the database because only those records with a valid value in every cell can be analysed ...

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