ðə pˈɛɹz kɹaɪtˈiəɹɪən ɪz mˈoːɹ dˈɪfɪkəlt tə dᵻskɹˈaɪb ænd tʊ ˈɪmplɪmənt, bˌʌt ɪɾ ˈædz sɪɡnˈɪfɪkənt ᵻlˈɪmᵻnˌeɪɾɪŋ pˈaʊɚ.
The pairs criterion is more difficult to describe and to implement, but it adds significant eliminating power.