be shared between the organisations. Privacy-preserving record linkage (PPRL) methods have been developed with the aim to link databases without the need of sharing the original sensitive values between the organisations that participate in a linkage. In PPRL, generally the attribute values of records to be compared are encoded or encrypted in some form. A popular such encoding technique used are Bloom filter, which allows approximate similarities to be calculated between encoded values without the need for sharing the corresponding sensitive plain-text values. At the end of the PPRL process only limited information about the record pairs classified as matches is revealed to the organisations that participate in the linkage process. The techniques used in PPRL must guarantee that no participating organisation, nor any external adversary, can compromise the privacy of the entities that are represented by records in the databases being linked. Mathematical model In an application with two files, A and B, denote the rows (records) by in file A and in file B. Assign characteristics to each record. The set of records that represent identical entities is defined by and the complement of set , namely set representing different entities is defined as . A vector, is defined, that contains the coded agreements and disagreements on each characteristic: where is a subscript for the characteristics (sex, age, marital status, etc.) in the files. The conditional probabilities of observing a specific vector given , are defined as and respectively. Applications Master data management Most Master data management (MDM) products use a record linkage process to identify records from different sources representing the same real-world entity. This linkage is used to create a "golden master record" containing the cleaned, reconciled data about the entity. The techniques used in MDM are the same as for record linkage generally. MDM expands this matching not only to create a "golden master record" but to infer relationships also. (i.e. a person has a same/similar surname and same/similar address, this might imply they share a household relationship). Data warehousing and business intelligence Record linkage plays a key role in data warehousing and business intelligence. Data warehouses serve to combine data from many different operational source systems into one logical data model, which can then be subsequently fed into a business intelligence system for reporting and analytics. Each operational source system may have its own method of identifying the same entities used in the logical