Table 2.

Factors often affect top and typical papers differently. Percentage of journals for which ${\beta }_{\mathrm{top}}\gtrless {\beta }_{\mathrm{half}}$ are reported. The right column, β_top≠β_half, is the sum of the two others.

property	factor	βtop>βhalf (%)	βtop<βhalf (%)	βtop≠βhalf (%)
length	no. characters (title)	2.6	44.4	47.0
	no. words (abstract)	8.3	29.4	36.7
			mean	41.9
complexity	Herdan's C (title)	18.7	8.5	27.2
	Herdan's C (abstract)	34.9	6.5	41.4
	z-index (title)	8.3	16.7	25.0
	z-index (abstract)	24.6	7.7	32.3
	fog index (abstract)	26.4	8.0	34.4
			mean	32.0
sentiment	arousal (title)	11.0	13.5	24.5
	arousal (abstract)	15.7	13.7	29.4
	valence (title)	16.1	11.3	27.4
	valence (abstract)	29.2	5.7	34.9
			mean	29.1
	no. authors	4.0	39.6	43.6
			overall mean	33.7