Argyrios Tasiopoulos, Christos Tsiaras, Stavros Toumpis, On the Cost/Delay Tradeoff of Wireless Delay Tolerant Geographic Routing, In: WoWMoM 2012, San Francisco, California, USA, 25 June 2012 - 28 June 2012, 2012-06-25. (Conference or Workshop Paper published in Proceedings)

In Delay Tolerant Networks (DTNs), there is a fundamental tradeoff between the aggregate transport cost of a packet and the delay in its delivery. We study this tradeoff in the context of geographical routing in wireless DTNs.
We ?rst specify the optimal cost/delay tradeoff, i.e., the tradeoff under optimal network operation, using a dynamic network construction termed the Cost/Delay Evolving Graph (C/DEG) and the Optimal Cost/Delay Curve (OC/DC), a function that gives the minimum possible aggregate transportation cost versus the maximum permitted delivery delay.
We proceed to evaluate the performance of two known delay tolerant geographic routing rules, i.e., MOVE and AeroRP, a delay tolerant version of the geographic routing rule that selects as next relay the node for which the cost-per-progress ratio is minimized, and ?nally two novel rules, the Balanced Ratio Rule (BRR) and the Composite Rule (CR). The evaluation is in terms of the aggregate packet transmission cost as a function of the maximum permitted packet delivery delay. Simulations show that CR achieves a cost/delay tradeoff that is overall the closest to the optimal one speci?ed by the OC/DC, while BRR achieves the smallest aggregate transmission costs for large packet delays and a ?xed transmission cost model. |
|
Sarah Mennicken, Elaine M. Huang, Hacking the Natural Habitat: An in-the-wild study of smart homes, their development, and the people who live in them, In: Pervasive 2012, Newcastle, UK, 19 June 2012 - 22 June 2012, 2012-06-19. (Conference or Workshop Paper published in Proceedings)

Commercial home automation systems are becoming increasingly common, affording the opportunity to study technology-augmented homes in real world contexts. In order to understand how these technologies are being integrated into homes and their effects on inhabitants, we conducted a qualitative study involving smart home professionals who provide such technology, people currently in the process of planning or building smart homes, and people currently living in smart homes. We identified motivations for bringing smart technology into homes, and the phases involved in making a home smart. We also explored the varied roles of the smart home inhabitants that emerged during these phases, and several of the challenges and benefits that arise while living in a smart home. Based on these findings we propose open areas and new directions for smart home research. |
|
Gregori Baetschmann, Identification and estimation of thresholds in the fixed effects ordered logit mode, Economics Letters, Vol. 115 (3), 2012-06. (Journal Article)
 
The paper proposes a new estimator for the fixed effects ordered logit model. In contrast to existing methods, the new procedure allows estimating the thresholds. The empirical relevance and simplicity of implementation is illustrated in an application to the effect of unemployment on life satisfaction. |
|
K Elbedweihy, S N Wrigley, F Ciravegna, Dorothee Reinhard, Abraham Bernstein, Evaluating Semantic Search Systems to Identify Future Directions of Research, In: Second International Workshop on Evaluation of Semantic Technologies, 28 May 2012 - 28 May 2012, 2012-05-28. (Conference or Workshop Paper published in Proceedings)
 
Recent work on searching the Semantic Web has yielded a wide range of approaches with respect to the style of input, the under- lying search mechanisms and the manner in which results are presented. Each approach has an impact upon the quality of the information re- trieved and the user’s experience of the search process. This highlights the need for formalised and consistent evaluation to benchmark the cov- erage, applicability and usability of existing tools and provide indications of future directions for advancement of the state-of-the-art. In this paper, we describe a comprehensive evaluation methodology which addresses both the underlying performance and the subjective usability of a tool. We present the key outcomes of a recently completed international evalu- ation campaign which adopted this approach and thus identify a number of new requirements for semantic search tools from both the perspective of the underlying technology as well as the user experience. |
|
Zhigang Feng, Time consistent optimal fiscal policy over the business cycle, In: Midwest Macro Meeting, 11 May 2012 - 13 May 2012, 2012-05-11. (Conference or Workshop Paper published in Proceedings)
 
This paper examines a dynamic stochastic economy with a benevolent government that cannot commit to future policies. Following Phelan and Stacchetti (2001), we consider sequential sustainable equilibria (SSE). We numerically solve for the set of equilibrium payoffs, and investigate whether the time consistency problem of capital income tax is quantitatively important. For a realistically calibrated economy, we find that the optimal sustainable capital income tax rate is pro-cyclical and close to zero on average, while the labor income tax is countercyclical.
Moreover, the welfare cost of no commitment is very small (0:22%) when compared with the Ramsey allocation. We also find that the best sustainable equilibrium outcome may achieve substantially higher social welfare than the
Markov-perfect equilibrium as considered by Klein, Krusell and Rios-Rull (2008). |
|
Jacob K Goeree, Jingjing Zhang, Inefficient markets, In: Working paper series / Department of Economics, No. No. 72, 2012-05. (Working Paper)
 
Traders' values and information typically consist of both private and common-value elements. In such environments, full allocative efficiency is impossible when the private rate of information substitution differs from the social rate (Jehiel and Moldovanu, 2001). We link this impossibility result to a failure of the efficient market hypothesis, which states that prices adequately reflect all available information (Fama, 1970, 1991). The intuition is that if prices were able to reveal all information then the common value would simply shift traders' private values by a known constant and full allocative efficiency would result. In a series of laboratory experiments we study price formation in markets with private and common values. Rational expectations, which form the basis for the efficient market hypothesis, predict that the introduction of common values has no adverse consequences for allocative and informational efficiency. In contrast, a "private" expectations model in which traders' optimal behavior depends on both their private and common-value information predicts that neither full allocative nor full informational efficiency is possible. We test these competing hypotheses and find that the introduction of common values lowers allocative efficiency by 28% on average, as predicted by the private expectations model, and that market prices differ significantly and substantially from their rational expectation levels. Finally, a comparison of observed and predicted payoffs suggests that observed behavior is close to the equilibrium predicted by the private expectations model. |
|
Björn Bartling, L Brandes, Daniel Schunk, Expectations as reference points: field evidence from experienced subjects in a competitive, high-stakes environment, In: Working paper series / Department of Economics, No. No. 73, 2012-05. (Working Paper)
 
We show that professional soccer players exhibit reference-dependent behavior during matches. Controlling for the state of the match and for unobserved heterogeneity, we show on a minute-by-minute basis that a player breaches the rules of the game, measured by the referee’s assignment of cards, with a significantly higher probability if his team is behind the expected match outcome, measured by pre-play betting odds of large professional bookmakers. We derive these results in two independent data sets, one from ten seasons of the German Bundesliga, the other from eight seasons the English Premier League, each with more than half a million minutes of play. |
|
Christian Rupietta, Uschi Backes-Gellner, Is apprenticeship training important for innovation in highly developed countries?, In: Spring Meeting of Young Economists, 26 April 2012 - 28 April 2012. 2012-04-26. (Conference Presentation)

|
|
Christian Rupietta, Uschi Backes-Gellner, Is apprenticeship training important for innovation in highly developed countries?, In: Annual Meeting of the Swiss Society of Economics and Statistics (SSES), 12 April 2012 - 13 April 2012. 2012-04-12. (Conference Presentation)

|
|
Martin Waldburger, Socio-Economic Aware Design of Future Network Technology
(Y.FNsocioeconomic), In: ITU Workshop on “Developments regarding telecommunication network architectures and services”, 02 April 2012 - 02 April 2012. 2012-04-02. (Conference Presentation)

|
|
Marco Casari, Jingjing Zhang, Christine Jackson, When do groups perform better than individuals?
A company takeover experiment, In: Working paper series / Institute for Empirical Research in Economics, No. No. 504, 2012-04. (Working Paper)
 
It is still an open question when groups perform better than individuals in intellectual tasks. We report that in a company takeover experiment, groups placed better bids than individuals and substantially reduced the winner’s curse. This improvement was mostly due to peer pressure over the minority opinion and to learning. Learning took place from interacting and negotiating consensus with others, not simply from observing their bids. When there was disagreement, what prevailed was not the best proposal but the one of the majority. Groups underperformed with respect to a “truth wins” benchmark although they outperformed individuals deciding in isolation. |
|
Jacob K Goeree, Luke Lindsay, Designing package markets to eliminate exposure risk, In: Working paper series / Department of Economics, No. No. 71, 2012-04. (Working Paper)
 
This paper reports results from a series of laboratory experiments designed to evaluate the impact of exposure risk on market performance. Exposure risk arises when there are complementarities between trades, e.g. when the purchase of a new house requires selling the old one. The continuous double auction (CDA), which has proven to be remarkably effective in a wide variety of settings, performs poorly in a treatment with high exposure risk: overall market efficiency is only 20% and there are many instances of no trade. In a parallel treatment with lower exposure risk, efficiency under the CDA is higher (55%) but is dominated, for instance, by a top-trading-cycles procedure that uses no money. The CDA's poor performance does not depend on whether house values are private information or common knowledge, indicating that exposure risk is due to strategic uncertainty not objective uncertainty about others' preferences. We introduce a simple package market and show that it effectively resolves exposure risk: efficiency levels are 82% and 89% respectively for the low and high exposure treatments. The proposed package market is a simple extension of the CDA and could potentially be applied in a variety contexts. |
|
Maria Saez-Marti, Yves Zenou, Cultural transmission and discrimination, In: Working paper series / Institute for Empirical Research in Economics, No. No. 348, 2012-04. (Working Paper)
 
Workers can have good or bad work habits. These traits are transmitted from one generation to the next through a learning and imitation process, which depends on parents' investment in the trait and the social environment where children live. We show that if a sufficiently high proportion of employers have taste-based prejudices against minority workers, their prejudices are always self-fulfilled in steady state and minority workers end up having, on average, worse work habits than majority workers. This leads to a ghetto culture. Affirmative Action can improve the welfare of minorities whereas integration can be beneficial to minority workers but detrimental to workers from the majority group. |
|
Jingjing Zhang, Communication in asymmetric group competition over public goods, In: Working paper series / Department of Economics, No. No. 69, 2012-04. (Working Paper)
 
This paper examines whether and how cheap talk communication can facilitate within-group coordination when two unequal sized groups compete for a prize that is shared equally among members of the winning group, regardless of their (costly) contributions to the group’s success. We find that allowing group members to communicate before making contribution decisions improves coordination. To measure how much miscoordination remains, we employ a control treatment where miscoordination is eliminated by asking group members to reach a unanimous contribution decision. Average group contributions are not significantly different in this control treatment. Cheap talk communication thus completely solves miscoordination within groups and makes group members act as a single agent. Furthermore, it is the larger group that benefits from communication at the expense of the smaller group. Finally, content analysis of group communication reveals that after the reduction of within-group strategic uncertainty, groups reach self-enforcing agreements on how much to contribute, designate specific contributors according to a rotation scheme, and quickly discover the logic of the mixed-strategy equilibrium. |
|
Emmanouil Mentzakis, Jingjing Zhang, An investigation of individual preferences: consistency across incentives and stability over time, In: Working paper series / Department of Economics, No. No. 70, 2012-04. (Working Paper)
 
This study compares individual preferences across incentives (i.e., hypothetical vs. real incentives) and over time (i.e. elicitation at two different points in time) in a choice experiment involving charitable donating decisions. We provide evidence of hypothetical bias but little evidence of instability of individual giving. There is significant heterogeneity in individual preferences, with real incentives either dampening or pronouncing the observed donating behaviour. Neither hypothetical bias nor instability is observed when we examine the propensity of individuals to make internally consistent decisions over identical choices. |
|
Marc Chesney, Alexander Kempf, The value of tradeability, In: NCCR FINRISK Working Paper Series, No. 710, 2012-03-15. (Working Paper)
 
This paper determines the value of asset tradeability in an option pricing framework. In our model, tradeability is valuable since it allows investors to exploit temporary mis-
pricings of stocks. The model delivers several novel insights on the value of tradeability: The value of tradeability is the larger, the higher the pricing e±ciency of the market is. Uncertainty increases the value of tradeablity, no matter whether the uncertainty results
from noise trading or from new information about the fundamental value of the stock.
The value of tradeability is the larger, the longer the illiquid stock cannot be traded and the more trading dates the liquid stock offers. |
|
Bruno S Frey, Lasse Steiner, Zufallswahl des Bundesrates, In: Weltwoche, p. 31, 14 March 2012. (Newspaper Article)

|
|
Simone Balestra, Uschi Backes-Gellner, When a door closes a window opens? Investigating the effects and determinants of involuntary separations, In: 15th Colloquium in Personnel Economics, 14 March 2012 - 16 March 2012. 2012-03-14. (Conference Presentation)

|
|
Christian Rupietta, Uschi Backes-Gellner, Are Apprenticeship-training Firms more Innovative than Non-apprenticeship-training Firms?, In: 15th Colloquium on Personnel Economics, 14 March 2012 - 16 March 2012. 2012. (Conference Presentation)

|
|
Cédric Jeanneret, Martin Glinz, Thomas Baar, Modeling the Purposes of Models, In: Modellierung 2012, GI, Bonn, 14 March 2012 - 16 March 2012, 2012-03-14. (Conference or Workshop Paper published in Proceedings)
 
Today, the purpose of a model is often kept implicit. The lack of explicit statements about a model's purpose hinders both its creation and its (re)use. In this paper, we adapt two goal modeling techniques, the Goal-Question-Metric paradigm and KAOS, an intentional modeling language, so that the purpose of a model can be explicitly stated and operationalized. Using some examples, we present how these approaches can document a model's purpose so that this model can be validated, improved and used correctly. |
|