Columbia Business School Research

Service systems are typically limited resource environments where scarce capacity is reserved for the most urgent customers. However, there has been a growing interest in the use of proactive service when a less urgent customer may become urgent while waiting. On one hand, providing service for customers when they are less urgent could mean that fewer resources are needed to fulfill their service requirement. On the other hand, using limited capacity for customers who may never need the service in the future takes the capacity away from other more urgent customers who need it now.

Problem definition: We study how online platforms can leverage the behavioral considerations of their users to improve their assortment decisions. Motivated by our collaboration with a dating company, we study how a platform should select the assortments to show to each user in each period to maximize the expected number of matches in a time horizon, considering that a match is formed if two users like each other, possibly on different periods.

The United States is one of the few countries that does not guarantee paid family leave (PFL) to workers. Proposals for PFL legislation are often met with opposition from employer organizations, which fear disruptions to business, especially among small employers. But there are limited data on employers’ views. The authors surveyed firms with 10 to 99 employees in New York and New Jersey on their attitudes toward PFL programs before and during the coronavirus disease 2019 (COVID-19) pandemic.

Climate change is a complex phenomenon that the public learns about both abstractly through media and education, and concretely through personal experiences. While public beliefs about global warming may be controversial in some circles, an emerging body of research on the ‘local warming’ effect suggests that people’s judgments of climate change or global warming are impacted by recent, local temperatures.

Smartphones have made it nearly effortless to share images of branded experiences. This research classifies social media brand imagery and studies user response. Aside from packshots (standalone product images), two types of brand-related selfie images appear online: consumer selfies (featuring brands and consumers’ faces) and an emerging phenomenon the authors term “brand selfies” (invisible consumers holding a branded product).

Employee misconduct is costly to organizations and has the potential to be even more common in gig and remote work contexts, in which workers are physically distant from their employers. There is, thus, a need for scholars to better understand what employers can do to mitigate misconduct in these nontraditional work environments, particularly as the prevalence of such work environments is increasing.

The social cost of nitrous oxide does not account for stratospheric ozone depletion. Doing so could increase its value by 20%. Links between nitrous oxide and other nitrogen pollution impacts could make mitigation even more compelling.

As the prospect of average global warming exceeding 1.5°C becomes increasingly likely, interest in supplementing mitigation and adaptation with solar geoengineering (SG) responses will almost certainly rise. For example stratospheric aerosol injection to cool the planet could offset some of the warming for a given accumulation of atmospheric greenhouse gases (1). However, the physical and social science literature on SG remains modest compared with mitigation and adaptation.

We examine how organizations of different types --public, non-profit and for-profit -- engage in consumer-benefiting misconduct (CBM) by examining which patients benefit from hospitals of the three types gaming the market for liver transplants. Consistent with our theory, we find that public firms are the least likely of the three organization types to engage in CBM.

This article empirically examines the magnitude of risk premiums for direct real estate investments on a global basis. As this article analyzes ex-ante risk premiums over more than 25 years consistently across the world, it enhances current knowledge about the regional differences between risk premiums and helps long-term investors with their global portfolio allocation over time. On a global level, the authors find a risk premium of 4.1% for Gordon’s growth and 3.7% for two-stage growth model. The periodic growth model shows a slightly lower risk premium of 3.1%.

The stalling of COVID-19 vaccination rates threatens public health. To increase vaccination rates, governments across the world are considering the use of monetary incentives. Here we present evidence about the effect of guaranteed payments on COVID-19 vaccination uptake. We ran a large preregistered randomized controlled trial (with 8286 participants) in Sweden and linked the data to population-wide administrative vaccination records.

Hotter temperature can reduce labor productivity, work hours, and labor income. The effects of heat are likely to be a joint consequence of both exposure and vulnerability. Here we explore the impacts of heat on labor income in the US, using regional wealth as a proxy for vulnerability. We find that one additional day >32 °C (90 °F) lowers annual payroll by 0.04%, equal to 2.1% of average weekly earnings. Accounting for humidity results in slightly more precise estimates.

We follow a representative panel of millions of consumers in the U.S. from 2007 to 2017 and document several facts on the long-term effects of the Great Recession. There were about six million foreclosures in the ten-year period after Lehman's collapse. Owners of multiple homes accounted for 25% of these foreclosures, while comprising only 13% of the market. Foreclosures displaced homeowners, with most of them moving at least once. Only a quarter of foreclosed households regained homeownership, taking an average four years to do so.

We study optimal team design. In our model, a principal assigns either heterogeneous agents to a team (a diverse team) or homogenous agents to a team (a specialized team) to perform repeated team production. We assume that specialized teams exhibit a productive substitutability (e.g., interchangeable efforts with decreasing returns to total effort), whereas diverse teams exhibit a productive complementarity (e.g., cross-functional teams).

This paper explores how discontinuities created by national borders can influence development across the Americas. We exploit the discontinuous nature of borders jointly with exogenous variation at the national level to identify discontinuous effects on proxies for economic development at the regional and pixel levels. We separate the effects of national institutions from local historical conditions. Our analysis yields three main findings. First, we find important discontinuities in development across national borders for the Americas.

Ideology plays a central role in consumer decisions, actions, and practices. While there have been numerous studies of ideological formations in specific consumption contexts, an integrative theoretical framework on consumption ideology has been missing. The theoretical framework presented in this article integrates systemic, social group, and social reality perspectives from social theory with prior consumer research to conceptualize consumption ideology as ideas and ideals that are related to consumerism and manifested in consumer behavior.

Climate scientists have long emphasized the importance of climate tipping points like thawing permafrost, ice sheet disintegration, and changes in atmospheric circulation. Yet, save for a few fragmented studies, climate economics has either ignored them or represented them in highly stylized ways. We provide unified estimates of the economic impacts of all eight climate tipping points covered in the economic literature so far using a meta-analytic integrated assessment model (IAM) with a modular structure.

Loss aversion can occur in riskless and risky choices. We present novel evidence on both in a non-student sample (660 randomly selected customers of a car manufacturer). We measure loss aversion in riskless choice in endowment effect experiments within and between subjects and find similar levels of average loss aversion in both. The subjects of the within study also participate in a simple lottery choice task which arguably measures loss aversion in risky choices. We find substantial heterogeneity in both measures of loss aversion.

We propose a new valuation method for private equity investments. First, we construct a cash-flow replicating portfolio for the private investment, using cash-flows on various listed equity and fixed income instruments. The second step values the replicating portfolio using a flexible asset pricing model that accurately prices the systematic risk in listed equity and fixed income instruments of different horizons.

We extract aggregate supply and aggregate demand shocks for the US economy from macroeconomic data on inflation, real GDP growth, core inflation and the unemployment gap. We first use unconditional non-Gaussian features in the data to achieve identification of these structural shocks while imposing minimal economic assumptions. We find that recessions in the 1970s and 1980s are better characterized as driven by supply shocks while later recessions were driven primarily by demand shocks. The Great Recession exhibited large negative shocks to both demand and supply.

This paper studies lockdown policy in a dynamic economy without government commitment. Lockdown imposes a cap on labor supply, which improves health prospects at the cost of economic output and consumption. A government would like to commit to the extent of future lockdowns in order to guarantee an economic outlook that supports efficient levels of investment into intermediate inputs. However, such a commitment is not credible, since investments are sunk at the time when the government chooses a lockdown. As a result, lockdown under lack of commitment deviates from the optimal policy.

Turning around distressed operations is an alternative response to underperformance — as contrasted with using transactions such as divestitures or resource redeployment to deal with troublesome assets during corporate renewal. Taking the perspective of private-equity owners whose interests are primarily financial, we explain how their approach to turnarounds of troubled companies may differ from that of managers within publicly traded firms who may envision the realization of longer-term sources of operating synergy among their firms' lines of business.

An historical review of managers' corporate renewal decisions reveals an evolving pattern away from using operating turnarounds in favor of making changes in corporate scope via transactions. One explanation for this progression away from operations is that financial valuation considerations supplant other inputs to managers' strategic logics — a reflection of the rising influence of financial institutions as activist owners.

Choice architecture tools, commonly known as nudges, powerfully impact decisions and can improve welfare. Yet it is unclear who is most impacted by nudges. If nudge effects are moderated by socioeconomic status (SES), these differential effects could increase or decrease disparities across consumers. Using field data and several preregistered studies, the authors demonstrate that consumers with lower SES, domain knowledge, and numerical ability are impacted more by a wide variety of nudges.

The Covid-19 pandemic crisis is ongoing, and it its wake has brought tremendous loss of life and economic loss, disruption and uncertainty. It has simultaneously brought to the surface important challenges about global healthcare systems, political systems and institutions and their response to the multi-faceted crisis, the connectedness and dependencies of modern economies through global supply chains, and issues of inequity, as manifested in segments of the population that have been most affected in terms of health and economic outcomes through the crisis.

In modern equity markets, participants have a choice of many exchanges at which to trade. Exchanges typically operate as electronic limit order books under a "price-time" priority rule and, in turn, can be modeled as multi-class FIFO queueing systems. A market with multiple exchanges can be thought of as a decentralized, parallel queueing system. Heterogeneous traders that submit limit orders select the exchange, i.e., the queue, in which to place their orders by trading off financial considerations against anticipated delays until their orders may fill.

Using text-mining, the authors develop version 1.0 of the Relevance to Marketing (R2M) Index, a dynamic index that measures the topical and timely relevance of academic marketing articles to marketing practice. The index assesses topical relevance drawing on a dictionary of marketing terms derived from 50,000 marketing articles published in practitioner outlets from 1982 to 2019. Timely relevance is based on the prevalence of academic marketing topics in practitioner publications at a given time.

People often discount future rewards, embracing smaller rewards that are delivered sooner rather than waiting for larger rewards delivered later. Previous behavioral research has demonstrated that people are more patient when options are presented as decisions to accelerate rather than delay consumption. This behavioral effect is well-established in the literature, but the underlying neural mechanisms have not been identified. We examined the neural correlates of delay and acceleration framing in intertemporal choice.

We formulate a dynamic no-arbitrage asset pricing model for equities and corporate bonds, featuring time variation in both risk aversion and economic uncertainty. The joint dynamics among cash flows, macroeconomic fundamentals and risk aversion accommodate both heteroskedasticity and non-Gaussianity. The model delivers measures of risk aversion and uncertainty at the daily frequency. We verify that equity variance risk premiums are very informative about risk aversion, whereas credit spreads and corporate bond volatility are highly correlated with economic uncertainty.

The major cities of the world have attracted a flurry of out-of-town (OOT) home buyers. Such capital inflows affect housing affordability, the spatial distribution of residents, construction, labor income, wealth, and ultimately welfare. We develop a spatial equilibrium model of a city with substantial heterogeneity among residents. We calibrate the model to the New York and Vancouver metro areas. The observed increase in OOT purchases is associated with 1.1% (5.0%) higher house prices and a 0.1% (0.34%) welfare loss in New York (Vancouver).

We propose a model of sovereign debt in which countries vary in their level of financial development, defined as the extent to which they can issue debt denominated in domestic currency in international capital markets. We show that low levels of financial development generate the "debt intolerance" phenomenon that plagues emerging markets: it reduces overall debt capacity, increases credit spreads, and limits the country's ability to smooth consumption.

This paper studies systemic risk in the interbank market. We first establish that in the German interbank lending market, a few large banks intermediate funding flows between many smaller periphery banks. We then develop a network model in which banks trade off the costs and benefits of link formation to explain these patterns. The model is structurally estimated using banks' preferences as revealed by the observed network structure before the 2008 financial crisis.

How much capital should financial intermediaries hold? We propose a general equilibrium model with a financial sector that makes risky long-term loans to firms, funded by deposits from savers. Government guarantees create a role for bank capital regulation. The model captures the sharp and persistent drop in macro-economic aggregates and credit provision as well as the sharp change in credit spreads observed during the Great Recession.

Does the pattern of social connections between individuals matter for macroeconomic outcomes? If so, where do differences in these patterns come from and how large are their effects? Using network analysis tools, we explore how different social network structures affect technology diffusion and thereby a country’s rate of growth. The correlation between high-diffusion networks and income is strongly positive. But when we use a model to isolate the effect of a change in social networks on growth, the effect can be positive, negative, or zero.

This article describes randomized field experiments implemented on two online labor market platforms examining the effect of employer charitable giving on a source of human capital that is becoming increasingly important to firms: the gig worker. It provides support that a message about charitable giving increases gig workers' willingness to complete extra work, and that pro-socially oriented gig workers are most responsive.

We estimated the effects of information avoidance and information seeking among parents of children diagnosed with ASD on age of diagnosis. An online survey was completed by 1,815 parents of children with ASD. Children of parents who self-reported that they had preferred "not to know," reported diagnoses around 3 months later than other children.

We study how small and medium enterprise (SME) lenders react to information about their competitors’ contracting decisions. To isolate this learning from lenders’ common reactions to unobserved shocks to fundamentals, we exploit the staggered entry of lenders into an information-sharing platform. Upon entering, lenders adjust their contract terms toward what others offer. This reaction is mediated by the distribution of market shares: lenders with higher shares or that operate in concentrated markets react less.

Global firms finance themselves through foreign subsidiaries, often shell companies in tax havens, which obscures their true economic location in official statistics. We associate the universe of traded securities issued by firms in tax havens with their issuer’s ultimate parent and restate bilateral investment positions to better reflect the financial linkages connecting countries around the world. Bilateral portfolio investment from developed countries to firms in large emerging markets is dramatically larger than previously thought.

We investigate risk and return in the major corporate bond markets of the developed world. We find that average returns increase with maturity and ratings class (where ratings go from high to low) and that this pattern is fit well by a global CAPM model, where the market consists of equity, sovereign and corporate bonds. Nonetheless, we strongly reject "asset class integration," finding a model which separates the market portfolio into its three components to fit much more of the corporate bond return variation.

The authors propose that purchasing luxury can be a unique means to engage in sustainable consumption because high-end products are particularly durable. Six studies examine the sustainability of high-end products, investigate consumer decision making when considering high-end versus ordinary goods, and identify effective marketing strategies to emphasize product durability, an important and valued dimension of sustainable consumption.

Shared Appreciation Mortgages (SAMs) feature mortgage payments that adjust with house prices. These mortgage contracts are designed to stave off home owner default by providing payment relief in the wake of a large house price shock. SAMs have been hailed as an innovative solution that could prevent the next foreclosure crisis, act as a work-out tool during a crisis, and alleviate fiscal pressure during a downturn. They have inspired Fintech companies to offer home equity contracts. However, the home owner's gains are the mortgage lender's losses.

We examine the statistical term structure model of cochrane and Piazzesi (2005) and its affine counterpart, developed in cochrane and Piazzesi (2008) in several out-of-sample analyzes. The model’s one-factor forecasting structure characterizes the term structures of additional currencies in samples ending in 2003. In post-2003 data one-factor structures again characterize each currency’s term structure, but we reject equality of the coefficients across the two samples.

In this paper, we examine a novel two-stage mechanism for selling government securities, wherein the dealers underwrite in the first stage the sale of securities, which are auctioned in stage 2 via either a discriminatory auction (DA) or a uniform price auction (UPA).