Discussion Papers

Discussion Paper No. 276
November 10, 2021

Do Robo-Advisors Make Us Better Investors?

Author:

Camila Back (LMU Munich)
Stefan Morana (Saarland University)
Martin Spann (LMU Munich)

Abstract:

Investors increasingly can obtain assistance from “robo-advisors,” artificial intelligence–enabled digitalized service agents imbued with anthropomorphic design elements that can communicate using natural language. The present article considers the impact of anthropomorphized robo-advisors on investment decisions, with a focus on their ability to mitigate investors’ behavioral biases. We study the well-documented disposition effect, which reflects investors’ greater propensity to realize past gains than past losses. In two induced-value laboratory experiments, the availability of a robo-advisor reduces (i.e., mitigates) investors’ disposition effect. This relationship is mediated by two simultaneous (indirect) effects: the extent of requests for the robo-advisor’s investment advice and perceptions of its socialness. These findings resonate with cognitive dissonance theory, which predicts that assigning responsibility to the advisor helps investors resolve a sense of discomfort that may arise after a financial loss. Anthropomorphic design elements alone are not sufficient to reduce the disposition effect, but they decrease investors’ propensity to seek advice, which offsets the positive (indirect) effect of perceived socialness. These results have implications for the ongoing automation of advisory services, as well as for improving decision making, and suggest some further research directions.

Keywords:

robo-advisors; artificial intelligence; advice; anthropomorphism; disposition effect;

JEL-Classification:

Download:

Open PDF file

Discussion Paper No. 275

Meta-Analysis of Empirical Estimates of Loss-Aversion

Author:

Taisuke Imai (LMU Munich)
Alexander Brown (Texas A&M University)
Ferdinand M. Vieider (Ghent University)
Colin F. Camerer (California Institute of Technology)

Abstract:

Loss aversion is one of the most widely used concepts in behavioral economics. We conduct a large-scale interdisciplinary meta-analysis, to systematically accumulate knowledge from numerous empirical estimates of the loss aversion coefficient reported during the past couple of decades. We examine 607 empirical estimates of loss aversion from 150 articles in economics, psychology, neuroscience, and several other disciplines. Our analysis indicates that the mean loss aversion coefficient is between 1.8 and 2.1. We also document how reported estimates vary depending on the observable characteristics of the study design.

Keywords:

loss aversion; prospect theory; meta-analysis;

JEL-Classification:

Download:

Open PDF file

Discussion Paper No. 274

Portfolio Liquidation under Factor Uncertainty

Author:

Ulrich Horst (HU Berlin)
Xiaonyu Xia (HU Berlin)
Chao Zhou (National University of Singapore)

Abstract:

We study an optimal liquidation problem under the ambiguity with respect to price impact parameters. Our main results show that the value function and the optimal trading strategy can be characterized by the solution to a semi-linear PDE with superlinear gradient, monotone generator and singular terminal value. We also establish an asymptotic analysis of the robust model for small amounts of uncertainty and analyze the effect of robustness on optimal trading strategies and liquidation costs. In particular, in our model ambiguity aversion is observationally equivalent to increased risk aversion. This suggests that ambiguity aversion increases liquidation rates.

Keywords:

stochastic control; uncertainty; portfolio liquidation; singular terminal value; superlinear growth gradient;

JEL-Classification:

Download:

Open PDF file

Discussion Paper No. 273

Alcohol and Short-Run Mortality: Evidence from a Modern-Day Prohibition

Author:

Kai Barron (WZB Berlin)
Debbie Bradshaw (SAMRC, University of Cape Town)
Charles D. H. Parry (SAMRC, Stellenbosch University)
Rob Dorrington (University of Cape Town)
Pam Groenewald (SAMRC)
Ria Laubscher (SAMRC)
Richard Matzopoulos (SAMRC, University of Capetown)

Abstract:

On July 13, 2020 a complete nation-wide ban was placed on the sale and transport of alcohol in South Africa. This paper evaluates the impact of this sudden and unexpected five-week alcohol prohibition on mortality due to unnatural causes. We find that the policy reduced the number of unnatural deaths by 21 per day, or approximately 740 over the five-week period. This constitutes a 14% decrease in the total number of deaths due to unnatural causes. We argue that this represents a lower bound on the impact of alcohol on short-run mortality, and underscores the severe influence that alcohol has on society—even in the short-run.

Keywords:

alcohol; mortality; economics; health; South Africa; COVID-19; violence;

JEL-Classification:

Download:

Open PDF file

Discussion Paper No. 272

Prices versus Quantities with Morally Concerned Consumers

Author:

Klaus M. Schmidt (LMU Munich)
Fabian Herweg (University of Bayreuth)

Abstract:

It is widely believed that an environmental tax (price regulation) and cap-and-trade (quantity regulation) are equally efficient in controlling pollution when there is no uncertainty. We show that this is not the case if some consumers (firms, local governments) are morally concerned about pollution and the pollution price is inefficiently low for political reasons. Emissions are lower and material welfare is higher with price regulation. Furthermore, quantity regulation gives rise to dysfunctional incentive and distribution effects. It shifts the burden of adjustment to the poor and discourages voluntary efforts to reduce pollution, while price regulation makes these efforts effective.

Keywords:

emissions trading; carbon tax; climate change; prices versus quantities; behavioral industrial organization;

JEL-Classification:

Download:

Open PDF file

Discussion Paper No. 271

Paying for Open Access

Author:

Lucas Stich (LMU Munich)
Martin Spann (LMU Munich)
Klaus M. Schmidt (LMU Munich)

Abstract:

Open access (OA) publishing upends the traditional business model in scientific publishing by requiring authors instead of readers to pay for the publishing-related costs. In this paper, we aim to elicit the willingness to pay (WTP) of authors for open access publishing. We conduct two separate field studies with different methodological approaches in different scientific disciplines (economics and medicine). First, a choice-based conjoint (CBC) analysis measures stated preferences of 243 economists in Germany, Austria, and Switzerland regarding their valuations of open access publishing in the “Top 5” economics journals. Second, a field experiment at four different open access medical journals elicits authors’ self-determined (“Pay-What-You-Want”) payments for open access publications. The results provide a plausible range of authors’ valuations, given that the first study rather provides an upper bound and the second study a lower bound of authors’ willingness to pay for open access publishing.

Keywords:

open access; willingness to pay; choice-based conjoint analysis; pay-what-you-want; field experiment;

JEL-Classification:

Download:

Open PDF file

Discussion Paper No. 270

Das Design von Klimaschutzverhandlungen

Author:

Klaus M. Schmidt (LMU Munich)

Abstract:

In seiner Thünen-Vorlesung vor dem Verein für Socialpolitik im Herbst 2020 hat Klaus Schmidt das Design von Klimaschutzverhandlungen untersucht. Er geht dabei von einem Vorschlag Martin Weitzmans aus, künftige Verhandlungen auf einen einheitlichen CO2-Mindestpreis zu fokussieren. Wäre ein solches Vorgehen demjenigen, wie es in den Abkommen von Paris und Kyoto praktiziert wurde, tatsächlich überlegen? Schmidt berichtet von zwei experimentellen Studien, in denen er gemeinsam mit Koautoren Licht auf diese Frage geworfen hat. Die Ergebnisse beider Studien unterstützen den Vorschlag von Weitzman.

Keywords:

Klimaschutzverhandlungen; Verhandlungsdesign; Reziprozität; CO2-Preis;

JEL-Classification:

Download:

Open PDF file

Discussion Paper No. 269

Signaling Motives in Lying Games

Author:

Tilman Fries (WZB Berlin)

Abstract:

This paper studies the implications of agents signaling their moral type in a lying game. In the theoretical analysis, a signaling motive emerges where agents dislike being suspected of lying and where some types of liars are more stigmatized than others. The equilibrium prediction of the model can explain experimental data from previous studies, in particular on partial lying, where some agents dishonestly report a non payoff-maximizing report. I discuss the relationship with previous theoretical models of lying that conceptualize the image concern as an aversion to being suspected of lying. The second half of the paper tests the theoretical predictions in an experiment. In contrast to previous literature, the experimental results show no evidence that image concerns influence lying behavior in the laboratory.

Keywords:

lying; image concerns; honesty; experiment;

JEL-Classification:

Download:

Open PDF file

Discussion Paper No. 268

All-Pay Competition with Captive Consumers

Author:

Jana Friedrichsen (HU Berlin)
Renaud Foucart (Lancaster University)

Abstract:

We study a game in which two firms compete in quality to serve a market consisting of consumers with different initial consideration sets. If both firms invest below a certain threshold, they only compete for those consumers already aware of their existence. Above this threshold, a firm is visible to all and the highest investment attracts all consumers. On the one hand, the existence of initially captive consumers introduces an anti-competitive element: holding fixed the behavior of its rival, a firm with a larger captive segment enjoys a higher payoff from not investing at all. On the other hand, the fact that a firm’s initially captive consumers can still be attracted by very high quality introduces a pro-competitive element: a high investment becomes more profitable for the underdog when the captive segment of the dominant firm increases. The share of initially captive consumers therefore has a non-monotonic effect on the investment levels of both firms and on consumer surplus. We relate our findings to competition cases in digital markets.

Keywords:

consideration set; regulation; all-pay auction; endogenous prize; digital markets;

JEL-Classification:

Download:

Open PDF file

Discussion Paper No. 267

Focusing Climate Negotiations on a Uniform Common Commitment Can Promote Cooperation

Author:

Klaus M. Schmidt (LMU Munich)
Axel Ockenfels (University of Cologne)

Abstract:

International cooperation on the reduction of greenhouse gas emissions, disarmament, or free trade needs to be negotiated. The success of such negotiations depends on how they are designed. In the context of international climate change policy, it has been proposed [e.g., Weitzman J of the Association of Environmental and Resource Economists (2014)] that shifting the negotiation focus to a uniform common commitment (such as a uniform minimum carbon price) would lead to more ambitious cooperation. Yet, a proof-of-concept for this important claim is lacking. Based on game theoretical analyses, we present experimental evidence that strongly supports this conjecture. In our study, human subjects negotiate contributions to a public good. Subjects differ in their benefits and costs of cooperation. Participation in the negotiations and all commitments are voluntary. We consider treatments in which agreements are enforceable, and treatments in which they have to be self-enforcing. In both situations, negotiating a uniform common commitment is more successful in promoting cooperation than negotiating individual commitments (as in the Paris agreement) and complex common commitments that tailor the commitment to the specific situation of each party (as attempted with the Kyoto protocol). Furthermore, as suggested by our model, a uniform common commitment benefits most from being enforced.

Keywords:

cooperation; negotiation design; common commitment; reciprocity; climate policy;

JEL-Classification:

Download:

Open PDF file

Older →← Newer