I have a log file with phone call data, described by 2 attributes: call_time, call_from. I want to discover some patterns in the data, using some statistical method. I don't have any predefined pattern to search for, I'd like to have some correlation index to spot out some specific unknown patterns, for example:
- when Caller_A makes a call, in 5 minutes Caller_B makes another call;
- when Caller_A makes more than 5 calls in 10 minutes, one call is to Caller_B
What kind of techniqe, tehory is more suitable for this problem? I read something about cross-correlation and auto-correlation but I don't see how to adapt to my problem.