Table 5. Characteristics of researchers with different publication patterns, 1996–2011, based on n = 10,000 randomly sampled authors for each pattern.

	UCP	Non-UCP	Skip	Skip-1
Main Field
Mathematics/Physics	15.7%	5.7%	5.3%	13.7%
Chemistry	12.0%	8.9%	8.6%	10.3%
Engineering	5.7%	9.6%	9.9%	6.9%
Earth Sciences	2.2%	2.2%	2.1%	3.4%
Biology	4.8%	6.0%	5.7%	6.5%
Biotechnology	2.0%	1.7%	1.6%	2.0%
Infectious Disease	4.7%	4.8%	4.9%	5.5%
Medical Research	33.0%	21.0%	21.0%	30.2%
Health Sciences	4.7%	7.1%	7.7%	5.2%
Brain Research	6.7%	5.1%	5.0%	6.9%
Social Sciences	1.5%	5.7%	6.4%	2.4%
Humanities	0.0%	0.3%	0.3%	0.0%
Computer Sciences/Electrical Engineering	6.9%	9.7%	9.1%	6.9%
Unknown*		12.4%	12.6%
Region
North America	31.8%	21.8%	22.4%	30.8%
Europe	42.7%	26.0%	26.3%	42.1%
Asia-Pacific	21.2%	27.2%	25.9%	20.5%
South America	1.4%	3.2%	3.3%	2.5%
Middle East	1.6%	2.9%	2.7%	2.1%
Africa	0.4%	1.5%	1.6%	0.9%
Unknown**	0.9%	17.4%	17.7%	1.1%
Sector
Academic	76.3%	56.8%	56.2%	72.7%
Hospital	4.2%	6.5%	6.9%	5.1%
Government	11.5%	8.0%	8.1%	11.7%
Industry	1.5%	6.5%	6.3%	2.9%
Society/Academy	2.3%	1.6%	1.4%	2.5%
Non-profit	1.5%	0.7%	0.5%	1.4%
Unknown**	2.6%	20.0%	20.7%	3.7%

*Only those papers for which can be linked to others through citation are classified. Thus, the main field for some authors with only one indexed publication cannot be determined.

**Both region and sector information are calculated based on an incomplete list of institutions. All major institutions (those publishing at least 50 papers per year) are accounted for. However, region, and sector information have not been curated for smaller institutions. Thus, the region and sector information for many authors cannot be determined for these less prolific institutions.