Long-term analysis of sex differences in prestigious authorships in cardiovascular research supported by the National Institutes of Health

Carolin Lerchenmüller, Marc Lerchenmueller, and Olav Sorenson

This study examines gender differences in the relative rates of men versus of women being listed in the prestigious first and last author positions on papers, changes in those rates over time, and differences in those rates across groups of articles. The probability of a woman being the first author on an article has risen over time to the point where she has better odds than a man of earning that position. But this advantage only exists for articles in less prominent journals. Women still have lower odds of receiving first authorships in the most prestigious journals. Progress in the rates at which women appear in the last author position, moreover, appears to have stalled, with women being named to these positions at nearly half the rate of men.

Circulation,137 (2018): 880-882 (OPEN ACCESS)

Legitimacy and the benefits of firm formalization

Valentina Assenova and Olav Sorenson

Entrepreneurs in many emerging economies start their firm informally, without registering with the state. We examine how informality at the time of founding affected the growth and performance of 12,146 firms in 18 countries across sub-Saharan Africa. Our findings indicate that entrepreneurs who registered their firms at founding enjoyed greater success, in terms of sales and employment. But these benefits varied widely across countries. Countries in which people perceive the government as being less corrupt, those in which they have greater trust in the courts, and those with lower levels of ethnic conflict had larger performance benefits associated with being formal. The benefits of firm formalization therefore appear to depend on the socio-political legitimacy of the state.

Organization Science, 28 (2017): 804-818 (OPEN ACCESS)

Regional ecologies of entrepreneurship

Olav Sorenson

Why do some regions produce more entrepreneurs than others? An ecological lens provides insight into this question: The demography of organizations in a region – particularly the proportion of small and young em- ployers – shapes many aspects of the environment for would-be entrepreneurs: (i) beliefs about the desirability of founding a firm, (ii) opportunities to learn about entrepreneurship and to build the abilities needed to succeed, and (iii) the ease of acquiring critical resources. Births of new industries and the demise of mature ones can therefore catalyze rapid changes in the rates of entrepreneurship that become self-reinforcing.

Journal of Economic Geography, 17 (2017): 959-974

Preprint available

Community and capital in entrepreneurship and economic growth

Sampsa Samila and Olav Sorenson

We argue that social and financial capital have a complementary relationship in fostering innovation, entrepreneurship and economic growth. Using panel data on metropolitan areas in the United States, from 1993 to 2002, our analyses reveal that social integration – in the microgeography of residential patterns – moderates the effect of venture capital, with more integrated regions benefitting more from expansions in the supply of financial capital. Our results remain robust to estimation with an instrumental variable to address potential endogeneity in the geography of venture capital. We also find some evidence for a similar effect from business associations. Our findings support the idea that social structure may contribute importantly to regional economic differences.

American Sociological Review, 82 (2017): 770-795

Summarized in Yale Insights

Video summary from Yale Insights

Entrepreneurs and social capital in China

Olav Sorenson

Does social capital operate differently in China? A long and vibrant literature on the concept of guanxi suggests not only that social capital might have a different character in China but also that it might prove more valuable there to employees and entrepreneurs alike. Drawing on unusually high quality data on Chinese executives, Burt and Burzynska (2017) explore the question of whether the same structural configurations of relationships appear associated with success in China as have been found in the West. Their short answer is yes. In this response, I comment on their article.

Management and Organization Review, 13 (2017): 275-280

Temporal issues in replication: The stability of centrality-based advantage

Yuan Shi, David M. Waguespack, and Olav Sorenson

The results of archival studies may depend on when researchers analyze data for at least two reasons: (1) databases change over time and (2) the sampling frame, in terms of the period covered, may reflect different environmental conditions. We examined these issues through the replication of Hochberg, Ljungqvist, and Lu’s (2007) research on the centrality of venture capital firms and their performance. We demonstrate (1) that one can reproduce the results in the original article if one uses data downloaded at roughly the same time as the original researchers did, (2) that these results remain fairly robust to even a decade of database updating, but (3) that the results depend sensitively on the sampling frame. Centrality only has a positive relationship to fund performance during boom periods.

Sociological Science, 4 (2017): 107-122 (OPEN ACCESS)

Expand innovation finance via crowdfunding

Olav Sorenson, Valentina Assenova, Guan-Cheng Li, Jason Boada, and Lee Fleming

Using data on Kickstarter campaigns and venture capital investments from 2009–2015, we explored whether crowdfunding expanded access to financial capital, in the sense of supporting innovation in more geographically diverse regions than venture capital. Over this period, crowdfunding has supported projects in many regions that have attracted little or no venture capital. Within regions, moreover, the evidence suggests that successful crowdfunding campaigns attract future venture capital investments and that they have been doing so at an increasing rate. Crowdfunding therefore appears to be expanding access to capital to a larger pool of innovators.

Science, 354 (2016): 1526-1528 (OPEN ACCESS)

Supplemental Materials

Replication data and analysis files

Geography, joint choices and the reproduction of gender inequality

Olav Sorenson and Michael S. Dahl

We examine the extent to which the gender wage gap stems from dual-earner couples jointly choosing where to live. If couples locate in places better suited for the man’s employment than for the woman’s, the resulting mismatch of women to employers will de- press women’s wages. Examining data from Denmark, our analyses indicate (i) that Danish couples chose locations with higher expected wages for the man than for the woman, (ii) that the better matching of men in couples to local employers could account for up to 36% of the gender wage gap, and (iii) that the greatest asymmetry in the apparent importance of the man’s versus the woman’s potential earnings occurred among couples with pre-school age children and where the male partner had accounted for a larger share of household income before the potential move.

American Sociological Review,81 (2016): 900-920

Podcast on the paper (interviewed by Cristobal Young)

Author disambiguation in PubMed: Evidence on the precision and recall of Author-ity among NIH-funded scientists

Marc Lerchenmueller and Olav Sorenson

We examined the usefulness (precision) and completeness (recall) of the Author-ity author disambiguation for PubMed articles by associating articles with scientists funded by the National Institutes of Health (NIH). In doing so, we exploited established unique identifiers —Principal Investigator (PI) IDs—that the NIH assigns to funded scientists. Analyzing a set of 36,987 NIH scientists who received their first R01 grant between 1985 and 2009, we identified 355,921 articles appearing in PubMed that would allow us to evaluate the precision and recall of the Author-ity disambiguation. We found that Author-ity identified the NIH scientists with 99.51% precision across the articles. It had a corresponding recall of 99.64%. Precision and recall, moreover, appeared stable across common and uncommon last names, across ethnic backgrounds, and across levels of scientist productivity.

PLoS One, 11 (2016): e0158731 (OPEN ACCESS)

Financing by and for the masses: An introduction to the special issue on crowdfunding

Lee Fleming and Olav Sorenson

This introduction to the special issue on crowdfunding begins by providing some information about the history and nature of the phenomenon. It then summarizes some of the key advantages and disadvantages of crowdfunding for entrepreneurs and for investors, introducing the various articles in the issue that explore these topics in greater depth. It concludes with some speculations regarding the possible future of the industry and its effects on entrepreneurship, innovation, and inequality.


California Management Review, 58 (2016): 5-19