18. The computer-program product of claim 17 , wherein the further processing further includes: for each iteration of at least one iteration: determining, after a most recent updating the set of current distributions, that another iteration is to be performed; and redefining, in response to determining that another iteration is to be performed, the set of current distributions to be the updated set of distributions and repeating the set of iteration operations; determining, after a most recent updating the set of current distributions, that another iteration is not to be performed; and wherein the topic-assignment output is identified in response to determining that another iteration is not to be performed, the topic-assignment output being based on the determination as to whether the word corresponds to a regular word or a seed word and the determination as to whether the word corresponds to a global topic or a discovered topic.
18. The computer-program product of claim 17 , wherein the further processing further includes: for each iteration of at least one iteration: determining, after a most recent updating the set of current distributions, that another iteration is to be performed; and redefining, in response to determining that another iteration is to be performed, the set of current distributions to be the updated set of distributions and repeating the set of iteration operations; determining, after a most recent updating the set of current distributions, that another iteration is not to be performed; and wherein the topic-assignment output is identified in response to determining that another iteration is not to be performed, the topic-assignment output being based on the determination as to whether the word corresponds to a regular word or a seed word and the determination as to whether the word corresponds to a global topic or a discovered topic. 19. The computer-program product of claim 18 , wherein the set of iteration operations include: generating a difference metric that represents a degree of difference between the set of current distributions and the updated set of distributions, wherein determining that another iteration is to be performed includes determining that the difference metric exceeds a predefined difference-metric threshold, wherein determining whether another iteration is to be performed includes: determining that another iteration is to be performed when the difference metric exceeds a predefined difference-metric threshold and when an iteration count is below an iteration-count threshold; and determining that another iteration is not to be performed when the difference metric does not exceed the predefined difference-metric threshold or when the iteration count is not below the iteration-count threshold.