1. A computer implemented method for managing financial accounts by changing at least one control variable including at least one of a credit line and an annual percentage rate, the method comprising: collecting and storing in one or more storage devices account data for a plurality of financial accounts, where the account data are associated with a plurality of variables; establishing at least one control variable and at least one behavior variable based on the plurality of variables; determining, by a data processor, a plurality of interval breakpoints for the at least one control variable and the at least one behavior variable; defining a plurality of account states based on the at least one control variable, the at least one behavior variable and the plurality of interval breakpoints; forming a transition matrix based at least in part on the account data and the plurality of account states; generating a Markov Decision Process (MDP) model based at least in part on the transition matrix; generating a policy lookup table based on an output of the Markov Decision Process model, the policy lookup table listing pricing actions to be taken in response to the plurality of account states, each pricing action comprising changing or maintaining at least one control variable including at least one of a credit line and an annual percentage rate; determining behavior variable data associated with a financial account; slotting the financial account into one of the plurality of account states based at least in part on the determined behavior variable data associated with the financial account; and determining, from the policy lookup table and based on the slotted account state, at least one pricing action to be taken on the financial account.