What can we do to secure the privacy of individuals while collecting and mining data?

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 Many data security-enhancing techniques have been developed to help protect data. Databases can employ a multilevel security model to classify and restrict data according to various security levels, with users permitted access to only their authorized level. It has been shown, however, that users executing specific queries at their authorized security level can still infer more sensitive information, and that a similar possibility can occur through data mining. Encryption is another technique in which individual data items may be encoded. This may involve blind signatures (which build on public-key encryption), biometric encryption (e.g., where the image of a person's iris or fingerprint is used to encode his or her personal information), and anonymous databases (which permit the consolidation of various databases but limit access to personal information only to those who need to know; personal information is encrypted and stored at different locations). Intrusion detection is another active area of research that helps protect the privacy of personal data.

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