A statistical generalization is a statement which is usually true, but not always true. Very often these are expressed using the word “most”, as in “Most conservatives favour welfare cuts.” Sometimes the word “generally” is used, as in “Conservatives generally favor welfare cuts.” Or, sometimes, no specific word is used at all, as in: “Conservatives favour welfare cuts.”

Fallacies involving statistical generalizations occur because the generalization is not always true. Thus, when an author treats a statistical generalization as though it were always true, the author commits a fallacy.