1. A method of operation in at least a portion of a system to detect at least one of fraudulent advertiser accounts or related advertiser account profiles suspected of being fraudulently generated, the system which includes at least one processor and at least one nontransitory processor-readable medium that stores at least one of processor-executable instructions or processor-executable data, the at least one nontransitory processor-readable medium communicatively coupled to the at least one processor, the method of operation comprising: generating, by the at least one processor, a set of advertiser accounts including at least a plurality of known fraudulent advertiser accounts and a plurality of known valid advertiser accounts; wherein each of the plurality of known fraudulent advertiser accounts and each of the plurality of known valid advertiser accounts has logically associated therewith a respective advertiser account profile that includes a number of advertiser account attributes; and wherein each of the number of advertiser account attributes has logically associated therewith at least one of a respective defined number of attribute values; at regular or irregular intervals, determining by the at least one processor: a value indicative of an initial probability of an advertiser account included in the set of advertiser accounts being at least one of a fraudulent advertiser account [p(y=S)] or a valid advertiser account [p(y=V)] based at least in part on: a number of known fraudulent advertiser accounts included in the set, a number of known valid advertiser accounts included in the set, and the total number of advertiser accounts included in the set; for the attribute values or a combination of attribute values associated with at least some of the advertiser account profiles included in the set of advertiser accounts, a respective value indicative of a likelihood of the attribute values or the combination of attribute values being associated with at least one of a fraudulent advertiser account [p(x j (i) |y=S)] or a valid advertiser account [p(x j (i) |y=V)]; and for each advertiser account in a plurality of active advertiser accounts, a conditional probability value [p(y=S|x (i) ] indicative of a probability that the respective advertiser account is fraudulent based on attribute values or combinations of attribute values included in the respective advertiser account profile and determined using the respective determined initial probabilities and determined likelihoods; designating, by the at least one processor, each active advertiser account with a respective determined conditional probability value at or above a defined first threshold value for removal from the plurality of active advertiser accounts; designating, by the at least one processor, each active advertiser account with a respective determined conditional probability value at or below a defined second threshold value for retention in the plurality of active advertiser accounts; designating, by the at least one processor, each active advertiser account with a respective determined conditional probability value falling between the defined first threshold value and the defined second threshold value for additional review; and at regular or irregular intervals, autonomously updating, by the at least one processor, the plurality of known fraudulent advertiser accounts included in the set of advertiser accounts to include at least some of the active advertiser accounts designated for removal from the plurality of active advertiser accounts by the at least one processor; preventing advertisers that are autonomously identified as fraudulent or suspected fraudulent advertisers from supplying advertising on webpages; attempting subsequent verification that the advertiser is not fraudulent; and reinstating the advertisers identified as fraudulent or suspected fraudulent advertisers to supply advertising on webpages if there is successful subsequent verification that the advertiser is not fraudulent.