Brad N. Greenwood

Show Me the Way to Go Home: An Empirical Investigation of Ride-Sharing and Alcohol Related Motor Vehicle Fatalities

In this work, we investigate how the entry of ride-sharing services influences the rate of alcohol related motor vehicle fatalities. While significant debate has surrounded ride-sharing, limited empirical work has been devoted to uncovering the societal benefits of such services (or the mechanisms which drive these benefits). Using a difference in difference approach to exploit a natural experiment, the entry of Uber Black and Uber X into California markets between 2009 and 2014, we find a significant drop in the rate of fatalities after the introduction of Uber X. Further, results suggest that not all services have the same effect, insofar as the effect of the Uber Black car service is intermittent and manifests only in selective locations (i.e., large cities). These results underscore the importance of coupling increased availability with cost savings in order to exploit the public welfare gains offered by the sharing economy. Practical and theoretical implications are discussed.

Matching Platforms and HIV Incidence: An Empirical Investigation of Race, Gender, and Socioeconomic Status

Although recent work has examined the adverse implications of Internet-enabled matching platforms, limited attention has been paid to whom the negative externalities accrue. We examine how the entry of platforms for the solicitation of casual sex influences the incidence rate of human immunodeficiency virus (HIV) infection by race, gender, and socioeconomic status. Using a census of 12 million patients subjected to a natural experiment in Florida, we find a significant increase in HIV incidence after platform implementation, with the largest effect accruing to historically at-risk populations (i.e., African Americans) despite documented lower rates of Internet utilization. Strikingly, our analysis reveals that HIV incidence increases in historically low-risk populations as well (e.g., individuals of higher socioeconomic status) and that men and women experience similar penalties. Identifying granular effects across subpopulations allows us to offer additional insight into the mechanisms by which matching platforms increase HIV incidence. We estimate the cumulative effect of platform entry over the five-year period of the study as 1,149 additional Floridians contracting HIV at a cost of

Can You Gig it? An Empirical Examination of the Gig-Economy and Entrepreneurial Activity

710 million. This paper was accepted by Lorin Hitt, information systems .

The When and Why of Abandonment: The Role of Organizational Differences In Medical Technology Life Cycles

We examine how the entry of gig-economy platforms influences local entrepreneurial activity. On one hand, such platforms may reduce entrepreneurial activity by offering stable employment for the un- and under-employed. On the other hand, such platforms may enable entrepreneurial activity by offering work flexibility that allows the entrepreneur to re-deploy resources strategically in order to pursue her nascent venture. To resolve this tension, we exploit a natural experiment, the entry of the ride-sharing platform Uber X and the on-demand delivery platform Postmates into local areas. We examine the effect of each on crowdfunding campaign launches at Kickstarter, the world’s largest reward-based crowdfunding platform. Results indicate a negative and significant effect on crowdfunding campaign launches, and thus local entrepreneurial activity, after entry of Uber X or Postmates. Strikingly, the effect appears to accrue primarily to unfunded and under-funded projects, suggesting that gig-economy platforms predominantly reduce lower quality entrepreneurial activity by offering viable employment for the un- and under-employed. We corroborate our findings with US Census data on self-employment, which indicate similar declines following the entry of Uber X, and with a small scale survey of gig-economy participants.

Unknowns of the gig-economy

Although the adoption of new technology has received significant attention in management research, investigations of abandonment have lagged. In this study, we examine differences in the rates of abandonment of medical technologies based on whether abandonment occurs in response to the emergence of a superior technology, or in light of new information questioning its efficacy. We link differences in responses to underlying differences in the mission and incentives of organizations. Examining coronary stents across three technological regime changes using a census of approximately 2 million patients admitted to Florida hospitals from 1995-2007, we show meaningful differences across three hospital types: for-profit, not-for-profit, and academic medical centers (AMCs), Results show that for-profit hospitals abandon the earlier generation in favor of a superior technology faster than not-for-profit hospitals, but this is not the case if the efficacy of the technology is questioned. Academic medical centers, however, have the highest rates of abandonment under both triggers. Importantly, we find that organizational factors dominate physician differences as explanatory factors for abandonment. Implications of these findings are two-fold. First, we identify the factors likely at play, i.e. the salience of norms of science and the corresponding trade-offs with economic benefits, when organizations make abandonment decisions. Second, our work underscores the importance of organizational mission, which dominates individual preferences in determining rates of abandonment.

Research Note—Tigerblood: Newspapers, Blogs, and the Founding of Information Technology Firms

Seeking multidisciplinary research into the rapidly evolving gig-economy.

Managers’ Political Beliefs and Gender Inequality among Subordinates: Does His Ideology Matter More than Hers?

In this paper, we study the impact of increases in media coverage from two sources, newspapers and blogs, on firm founding rates in the context of technology-based entrepreneurship. Although increasing work in information systems (IS) has begun to investigate the effect of user-generated content on entrepreneurial behavior, limited attention has been devoted to how media affects firm founding or the boundary conditions of such an effect. Arguing for the direct effect of increased discourse in traditional and user-generated media in the information technology (IT) industry, results suggest that discourse in traditional media and blogs strongly influences IT firm founding rates. We further consider the differential impacts of media discourse on firm founding in different IT subsectors, over time, and in different locations. We test our hypotheses using entrepreneurial firm founding data from VentureXpert from 1998 to 2007, social media data from the three largest blogging platforms, and traditional media co...

Patient–physician gender concordance and increased mortality among female heart attack patients

Significant prior research has examined the role that managers play in producing gender inequality in organizations, but little work has directly explored the role of managers’ beliefs and attitudes. We bring managers’ beliefs and attitudes to the fore by theorizing about the relationship between managers’ political ideology, situated on a liberal-conservative continuum, and the level of gender inequality among their subordinates. Using novel microdata from the legal services industry, we find that law offices whose partners are more liberal have lower rates of gender inequality in the hiring and promotion of associate attorneys. Further, examining the interaction between partners’ gender and partners’ political ideology, we find that the political ideology of male partners is significantly more powerful in affecting these differences as compared with the ideology of female partners. Finally, we do not find evidence that these differences are driven by selection, in the form of higher quality female associates choosing to work for more liberal partners. We discuss the implications of our theory and findings for individual careers and firm performance.

Traders, Guns, and Money: The Effects of Mass Shootings on Stock Prices of Firearm Manufacturers in the U.S.

Significance A large body of medical research suggests that women are less likely than men to survive traumatic health episodes like acute myocardial infarctions. In this work, we posit that these difficulties may be partially explained, or exacerbated, by the gender match between the patient and the physician. Findings suggest that gender concordance increases a patient’s probability of survival and that the effect is driven by increased mortality when male physicians treat female patients. Empirical extensions indicate that mortality rates decrease when male physicians practice with more female colleagues or have treated more female patients in the past. We examine patient gender disparities in survival rates following acute myocardial infarctions (i.e., heart attacks) based on the gender of the treating physician. Using a census of heart attack patients admitted to Florida hospitals between 1991 and 2010, we find higher mortality among female patients who are treated by male physicians. Male patients and female patients experience similar outcomes when treated by female physicians, suggesting that unique challenges arise when male physicians treat female patients. We further find that male physicians with more exposure to female patients and female physicians have more success treating female patients.

Ending the Mending Wall: Herding, Media Coverage, and Colocation in IT Entrepreneurship

We investigate how mass shootings influence the stock price of firearms manufacturers. While it is well known that mass shootings lead to increased firearms sales, the response from financial markets is unclear. On one hand, given the observed short-term increase in demand, firearm stock prices may rise due to the unexpected financial windfall for the firm. On the other, mass shootings may result in calls for regulation of the industry, leading to divestment of firearms stocks in spite of short-term demand. We examine this tension using a market movement event study in the wake of 93 mass shootings in the U.S. between 2009 and 2013. Findings show that stock prices of firearm manufacturers decline after shootings; each event reducing prices between 22.4 and 49.5 basis points, per day. These losses are exacerbated by the presence of a handgun and the number of victims killed, but not affected by the presence of children or location of the event. Finally, we find that these effects are most prevalent in the period 2009–2010 but disappear in later events, indicating that markets appear to have accepted mass shootings as the “new normal.”