3. The device of claim 2 wherein said independent error templates and said linked error templates are composite templates which correspond to a class of erroneously matched patterns.
3. The device of claim 2 wherein said independent error templates and said linked error templates are composite templates which correspond to a class of erroneously matched patterns. 4. The device of claim 3 further comprising means for modifying said comparison means whenever said test template is most closely matched to a linked error template, said modification being to discard from further consideration said linked error template, its specified reference template, and all independent error templates.