MANAGEMENT SCIENCE Articles in Advance, pp. 1–19 http://pubsonline.informs.org/journal/mnsc ISSN 0025-1909 (print), ISSN 1526-5501 (online) Investment in a Smaller World: The Implications of Air Travel for Investors and Firms Zhi Da,a Umit G. Gurun,b Bin Li,c Mitch Warachkad a University of Notre Dame, Notre Dame, Indiana 46556; b University of Texas at Dallas, Richardson, Texas 75080; c University of Oklahoma, Norman, Oklahoma 73019; d Chapman University, Orange, California 92866 Contact: [email protected] (ZD); [email protected] (UGG); [email protected], http://orcid.org/0000-0001-6244-8490 (BL); [email protected], http://orcid.org/0000-0003-3484-6509 (MW) Received: February 10, 2017 Abstract. A large literature reports that proximity influences investment. We extend the Revised: February 6, 2018; November 19, 2018; measurement of proximity beyond distance and report that air travel reduces local in- May 29, 2019 vestment bias. This result is confirmed using the initiation of connecting flights through July 12, 2019 Accepted: recently opened air hubs because investment at destinations served by these connecting Published Online in Articles in Advance: fl November 27, 2019 ights increases after, not before, their initiation. Air travel also broadens the investor base of firms and lowers their cost of equity by approximately 1%. Overall, air travel improves https://doi.org/10.1287/mnsc.2019.3452 the diversification of investor portfolios and lowers the cost of equity for firms. Copyright: © 2019 INFORMS History: Accepted by Tyler Shumway, finance. Mobility of population is death to localism. —Frederick and a destination, where firms are headquartered. Jackson Turner, The Significance of the Frontier in American Our results are similar if air trafficisdefined using the History, 1873 number of flights between an origin and destination. fi fi The literature on local investment bias examines the We nd that higher air traf cincreasesthenumberof proximity of investors to the firms in which they invest. institutional investors at the origin with equity positions fi This literature measures proximity as the distance be- in rms at the destination and the dollar-denominated fi tween an investor’s location and the location of a firm’s amount of these positions. Thus, air traf c improves fi headquarters. However, aviation has made the world the diversi cation of investor portfolios. The larger fi smaller by dramatically reducing the time required to portfolio allocations to distant rmsasaresultofair travel long distances. Once airborne, flying is more traffic also reduce local investment bias. than 10 times faster than driving. We study the im- To address the endogenous relation between air plications of air travel for investor portfolios and the traffic and investment opportunities, we examine the cost of equity for firms. Instead of focusing on firms initiation and cancellation of connecting flights at- headquartered within a fixed distance of investors, tributable to recently opened air hubs. Destinations we examine air travel’sinfluence on portfolio in- with limited investment opportunities are most af- vestment throughout the United States. We also ex- fected by recently opened air hubs because destina- amine air travel’sinfluence on the cost of equity to tions with exceptional investment opportunities are determine whether a more geographically diversified served by direct flights. To clarify, portfolio in- investor base is associated with a lower cost of equity vestment near the air hub is not examined because the (Merton 1987). origin and destination of a connecting flight are The intuition underlying our paper’s first empirical distinct from the hub’s location. Intuitively, our re- test is simple: suppose air traffic between Los Angeles, sults are confirmed using variation in air trafficbe- California, and Austin, Texas, increases relative to air tween two peripheral nodes in a network (origin and traffic between other cities and Austin. We examine destination) whose connectivity is reoptimized in whether investors in Los Angeles increase their port- response to the addition of a central node (air hub). folio allocations in firms headquartered in Austin by For example, the 1997 opening of an air hub in Los acquiring shares from investors in other cities. This Angeles (LAX) led to the initiation of connecting reshuffling of the investor base resulting from varia- flights between Austin and several cities in California, tion in air trafficisdifficult to attribute to investment such as San Jose. We hypothesize that portfolio in- opportunities in Austin because these opportunities vestment in Austin firms by San Jose investors (and are available to investors throughout the United States. vice versa) increases following the initiation of a Air traffic represents the number of air passengers connecting flight through LAX. The decision to locate flying between an origin, where investors are located, an air hub in Los Angeles is not driven by investment 1 Da et al.: Investment in a Smaller World 2 Management Science, Articles in Advance, pp. 1–19, © 2019 INFORMS opportunities in either San Jose or Austin although flight through a recently opened air hub increases portfolio investment in Los Angeles is not examined portfolio investment in firms headquartered at the by our analysis of connecting flights through LAX.1 destination but decreases the returns of investors at Moreover, we confirm that the number of investors the origin. This evidence is consistent with air traffic’s and their dollar-denominated portfolio holdings both ability to lower expected returns through improved increase after the initiation of connecting flights through risk sharing (Merton 1987). a recently opened air hub but not before an air hub’s To examine air travel’simpactonthecostofequity, opening. Thus, we conclude that portfolio investment we define air passenger volume as the number of air- responds to air traffic. Conversely, the reverse impli- line passengers entering and departing a destination. cation that air traffic responds to investment oppor- This metric ignores the location of investors because tunities is not supported. improved risk sharing can be achieved by attracting port- To examine local investment bias, we define air folio investment from anywhere in the United States. traffic share as the fraction of total air trafficfroman We report that greater air passenger volume broadens origin to a destination. These fractions are analogous the investor base of small firms and lowers their cost of to portfolio weights. Air traffic share has a positive equity by approximately 1%. Air hub openings confirm relation with the market-adjusted portfolio weights both these implications of air travel. To quantify the eco- assigned by investors located at the origin to firms nomic impact of air traffic on expected equity returns, headquartered at the destination. Therefore, by fa- the Gordon growth model implies that this reduction in cilitating portfolio investment in distant firms, air the cost of equity increases the valuation of a typical firm travel mitigates local investment bias. by 20%.3 Overall, the initiation of a connecting flight After repeating our empirical tests separately in each through a recently opened air hub results in firms at the calendar year, we find consistent results throughout the destination attracting more institutional investors. This sample period. Consequently, the impact of air travel on broadening of their investor base lowers their cost of portfolio investment is not diminishing over time. equity, which partially explains the insignificant impact Furthermore, air traffic on low-cost airlines miti- of air travel on investor returns. gates local investment bias although low-cost airlines Several recent studies examine the economic im- are less likely to be flown by institutional investors plications of air travel. Giroud (2013)concludesthat and senior management traveling for business pur- air travel facilitates internal monitoring within firms poses. However, air traffic does not increase the risk- that improves their performance, and Bernstein et al. adjusted return of investor portfolios, suggesting that (2016) use airline data to examine the performance of air travel does not enable investors to gain an infor- venture capitalists. These studies highlight the return mational advantage. This finding parallels the con- implications of air travel. Our study finds air travel clusion of Pool et al. (2012) that familiarity motivates benefits investors through an alternative channel: im- fund managers to overweight firms that do not gen- proved diversification that reduces local investment erate higher returns.2 Besides familiarity, the ability of bias. Our study also identifies a benefit of air travel for full-service airlines to increase portfolio investment in firms: a lower cost of equity because of improved risk distant firms is consistent with air travel’s ability to sharing. facilitate monitoring because monitoring does not necessarily result in higher risk-adjusted returns. 1. Data We also examine the impact of air travel on cor- The Research and Innovative Technology Adminis- porate acquisitions. Greater air trafficincreasesthe tration(RITA)attheU.S.DepartmentofTransporta- likelihood that firms at the destination are acquired tion publishes monthly data on commercial airline by firms at the origin. However, as with risk-adjusted flights and air passengers starting from January 1990. portfolio returns, air travel does not improve the We study all flights with scheduled passenger ser- returns of acquiring