Using Odds for Weighted Probabilities

Section 4-1 USING ODDS FOR WEIGHTED PROBABILITIES

Record comparison weights are based on odds for the kind of comparison being made between the fields of the record. Odds is an expression related to probability ([pi]) as follows:

(4.1)

It is possible to measure the conditional probability that a field agrees, where the condition is that the comparison is matched and data is present. We do this by isolating a set of records that we know to belong to duplicate groups. We have been calling this measure reliability. We do not need the duplicate groups to measure the probability of agreement when the comparison is not matched though present. This is what we have called general coincidence. We use the duplicate groups if the additional accuracy of an entity coincidence is desired.

		4-1.1.	Odds of field value agreement.
		4-1.2.	Odds of field value disagreement.
		4-1.3.	Odds of field value missing.
		4-1.4.	Changing odds to weights.
		4-1.5.	Calculating record comparison weights.