1. A computer-implemented method for determining examinee attribute mastery levels, the method comprising: (a) for each of one or more items on an assessment, determining with a computer an estimated value for each of one or more item parameters by: performing a Metropolis-Hastings within Gibbs step for updating an estimate of a probability of correctly applying all attributes described in a Q-matrix for an item if each attribute for the item is mastered; performing a Metropolis-Hastings within Gibbs step for updating an estimate of a penalty imposed on the probability of correctly applying all attributes in the Q-matrix if an examinee has not mastered a particular attribute; and performing a Metropolis-Hastings within Gibbs step for updating an estimate of a measure of whether the attributes in the Q-matrix adequately describe attributes necessary for answering the item; (b) for each of one or more proficiency space parameters, determining with a computer an estimated value for the proficiency space parameter; (c) for each of one or more examinee parameters, determining with a computer an estimated value for the examinee parameter for each examinee; (d) repeating (a) through (c) a predetermined number of iterations; and (e) determining with a computer and outputting one or more examinee attribute mastery levels based on the item parameters, proficiency space parameters, and examinee parameters.