Principles and Rules of Part-of-Speech Annotation

In this chapter, we describe some principles and rules that we apply during the process of part-of-speech (POS) annotation on a written text corpus. For various practical and theoretical reasons, these principles and rules become useful and relevant for overcoming many unwanted hurdles in POS annotation. We also describe here the strategies that we apply when we formulate some algorithms for the automatic assignment of grammatical values to words in a text. Although we address theoretical and practical issues of POS annotation, we do not talk about technical and computational issues which are important when a computer system is engaged for this kind of work. Since the target readers of this chapter are students of linguistics who have limited or zero exposure to computation, we keep these technical and computational issues beyond this chapter. We primarily focus on some linguistic and theoretical aspects of the problem. We keep these issues relatively simple as an area of general inquiry, so that non-experts and common readers can get ideas about how words in a text are annotated at the POS level, and how the principles and rules are to be used during this work. This chapter has two parts: in Part I, we propose some principles that are to be followed during POS annotation; and in Part II, we define some rules which are to be adopted during the actual work of POS annotation. Supporting examples are taken from English and Bengali text corpus. This chapter imparts necessary guidance to the new generation of scholars about the nature and characteristics of POS annotation and how proper reference to these principles and rules can make the subsequent works of text processing easy and simplified.