A method for securing access to a resource, the method comprising performing, by a computer system: storing a plurality of previously received access requests and parameters of the plurality of previously received access requests; storing validity information corresponding to the plurality of previously received access requests, the validity information indicating whether each access request of the plurality of previously received access requests is valid or invalid; generating a potential access rule including one or more conditions; determining a first set of previously received access requests of the plurality of previously received access requests, each previously received access request of the first set including one or more parameters that satisfy the one or more conditions of the potential access rule; segmenting the first set of previously received access requests into a plurality of time-based subsets of access requests; determining a predictive percentage for each of the plurality of time-based subsets based on the validity information corresponding to each previously received access request of the time-based subsets; determining a detection stability rating of the potential access rule by comparing the plurality of predictive percentages and computing a variation of the plurality of predictive percentages across each of the time-based subsets; selecting the potential access rule to be included in an operational set of access rules based on the detection stability rating of the potential access rule compared to detection stability ratings of other access rules; loading the operational set of access rules into a system memory; receiving, over a network from a plurality of devices, a plurality of real-time access requests; accessing the system memory to obtain the operational set of access rules when one of the plurality of real-time access requests is received from a first device of the plurality of devices; using the operational set of access rules to determine an access request outcome for the one real-time access request; and providing access to the resource based on the access request outcome. storing a plurality of previously received access requests and parameters of the plurality of previously received access requests; storing validity information corresponding to the plurality of previously received access requests, the validity information indicating whether each access request of the plurality of previously received access requests is valid or invalid; generating a potential access rule including one or more conditions; determining a first set of previously received access requests of the plurality of previously received access requests, each previously received access request of the first set including one or more parameters that satisfy the one or more conditions of the potential access rule; segmenting the first set of previously received access requests into a plurality of time-based subsets of access requests; determining a predictive percentage for each of the plurality of time-based subsets based on the validity information corresponding to each previously received access request of the time-based subsets; determining a detection stability rating of the potential access rule by comparing the plurality of predictive percentages and computing a variation of the plurality of predictive percentages across each of the time-based subsets; selecting the potential access rule to be included in an operational set of access rules based on the detection stability rating of the potential access rule compared to detection stability ratings of other access rules; loading the operational set of access rules into a system memory; receiving, over a network from a plurality of devices, a plurality of real-time access requests; accessing the system memory to obtain the operational set of access rules when one of the plurality of real-time access requests is received from a first device of the plurality of devices; using the operational set of access rules to determine an access request outcome for the one real-time access request; and providing access to the resource based on the access request outcome.