Table 3.

Memorisation assessment for 1K samples per n-gram group in the top+meta train-gen-mhr model. high denotes n-grams from the upper frequency quartile; low—n-grams from the lower frequency quartile; %,in denotes percentage of target n-grams in the input key phrases; and %,out—in the respective generated output. Highest PPL values are highlighted in bold.

		2-gram		3-gram		5-gram
		High	Low	High	Low	High	Low
%, In		16	40	4	12	0.3	0.8
%, Out		48	48	43	34	41	29
PPL, K		18	25	17	24	21	24