Computation of weights

Match weights measure the extent to which two records match based on the designated matching criteria. Record pairs with higher weights are a stronger match than record pairs with lower weights.

The odds ratio is the ratio of the odds that an event occurs in one group to the odds that the event occurs in another group. An odds ratio of one (1) implies that the event is equally likely in both groups. An odds ratio greater than one (>1) implies that the event is more likely in the first group. An odds ratio less than one (< 1) implies that the event is less likely in the first group.

The weight calculation for a column uses the odds ratio of the likelihood that the values are the same and the record pair is a match versus the likelihood that the odds of the values are the same and the record pair is a nonmatch. Using such an odds ratio minimizes the number of clerical pairs for the chosen cutoff values.