15. A method, comprising: a computer system receiving an unknown text sample that includes user-generated content (UGC) submitted to a first website in connection with a user comment about a product or service, wherein the unknown text sample includes one or more words in one or more human languages; the computer system classifying the unknown text sample into one of a plurality of categories, wherein a first one of the plurality of categories corresponds to content prohibited from being published on a particular website, and wherein a second one of the plurality of categories corresponds to content allowed to be published on the particular website; wherein the classifying comprises: generating a set of features from the unknown text sample; performing one or more dimension reduction operations on the generated set of features; and using a first set of criteria and data generated from the performing the one or more dimension reduction operations to determine a classification for the unknown text sample, wherein the first set of criteria was established by a training procedure that includes: performing one or more dimension reduction operations on features within text samples in a training set that includes text samples for each of the plurality of categories; populating a data structure having entries corresponding to text samples in the training set, wherein the populating is based on the one or more dimension reduction operations; using a non-linear classifier on the data structure to establish the first set of criteria; wherein each text sample in the training set is made up of characters within a text character set having C characters, wherein features corresponding to text samples in the training set have N characters, and wherein populating an entry in the data structure for a given text sample includes a dimension reduction operation such that a corresponding feature value is reduced from C N possible values to not greater than C N-1 possible values, where N is an integer greater than or equal to 3 and C is an integer greater than or equal to 20.
15. A method, comprising: a computer system receiving an unknown text sample that includes user-generated content (UGC) submitted to a first website in connection with a user comment about a product or service, wherein the unknown text sample includes one or more words in one or more human languages; the computer system classifying the unknown text sample into one of a plurality of categories, wherein a first one of the plurality of categories corresponds to content prohibited from being published on a particular website, and wherein a second one of the plurality of categories corresponds to content allowed to be published on the particular website; wherein the classifying comprises: generating a set of features from the unknown text sample; performing one or more dimension reduction operations on the generated set of features; and using a first set of criteria and data generated from the performing the one or more dimension reduction operations to determine a classification for the unknown text sample, wherein the first set of criteria was established by a training procedure that includes: performing one or more dimension reduction operations on features within text samples in a training set that includes text samples for each of the plurality of categories; populating a data structure having entries corresponding to text samples in the training set, wherein the populating is based on the one or more dimension reduction operations; using a non-linear classifier on the data structure to establish the first set of criteria; wherein each text sample in the training set is made up of characters within a text character set having C characters, wherein features corresponding to text samples in the training set have N characters, and wherein populating an entry in the data structure for a given text sample includes a dimension reduction operation such that a corresponding feature value is reduced from C N possible values to not greater than C N-1 possible values, where N is an integer greater than or equal to 3 and C is an integer greater than or equal to 20. 17. The method of claim 15 , wherein the classifying also uses a second set of criteria established by a different training procedure that operates on the text samples in the training set using different features, different dimension reduction operations, a different data structure, and a different non-linear classifier.