Patent ID: 8090648

Claim:
A computer system comprising: at least one data processor; memory coupled to the at least one data processor for encoding instructions comprising: a frequency determination component to determine frequency information associated with a plurality of data transactions, the plurality of data transactions comprising telephone calls; a conversion component to convert the frequency information into a frequency variable; and a prediction component to predict fraud based on the frequency variable from the conversion component; wherein, for each caller of a telephone call, a profile is generated mathematically summarizing calling patterns of the caller, the profile being maintained and updated upon each call, wherein the conversion component converts the frequency information into the frequency variable using a frequent-number list method, the frequent-number list method utilizing three tables stored in the profile, a number table being a table of n most frequently dialed destination numbers, a frequency table comprising a table of pseudo-frequencies of corresponding n most frequently dialed destination numbers, and a ranking table for ranking the n most frequently dialed destination numbers; wherein upon each new call: the number table is looked up to determine that a destination number for the new call is listed in the number table; a rank of the destination number for the new call is retrieved from the ranking table; frequencies in the frequency table are decayed by a multiplicative factor; the number table and the frequency table are updated to reflect the new call; and the ranking table is updated according to the updates to the number table and the frequency table.