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This paper experimentally investigates risk taking in contest schemes by implementing a stopping task based on Seel and Strack (2013). In this stylized setting, managers with contest payoffs have an incentive to delay halting projects with a negative expectation, with the induced inefficiency being highest for a moderately negative drift. The experiment systematically varies the negative drift (between-subjects) and the payoff incentives (within-subject). We find evidence for risk taking in all our treatment conditions, with the non-monotonicity at least as pronounced as predicted. Contrary to the theoretical predictions, a similar pattern of behaviour persists even without contest incentives, suggesting contest incentives are not the only driver of risk-taking behaviour. Instead, observed behaviour violates expected utility maximization and is consistent with some intrinsic motivation for taking risk and myopic reasoning about the opponent. We explore the interplay between intrinsic incentives and the payment scheme and find that contest incentives might crowd out an intrinsic inclination to risk-taking. [ABSTRACT FROM AUTHOR]

Internal Wave (IW) is a kind of wave that occurs below the sea surface. Compared with surface wave, the force applied to underwater structures is more destructive. This paper experimentally investigates the interaction process between Internal Solitary Wave (ISW) and submerged body, and proposes two new dimensionless parameters and uses these two dimensionless parameters to analyze the force of the submerged body with different ISW amplitude and submerged depth. At the same time, these two dimensionless parameters can be used to classify the lateral force and vertical force of the submerged body. Finally, the influence of velocity and acceleration field on the force of the submerged body is considered. The results show that the extreme value will increase with the increase of ISW amplitude. The variation of horizontal force under d 0 ∗ condition is completely different from that of d + ∗ and d − ∗. The dimensionless number L ∗ affects the action time, and the dimensionless number d ∗ affects the change rule of vertical force. The horizontal inertial force plays a dominant role in the horizontal force. When d ∗ = − 1.17 , the inertial force plays a dominant role in the vertical force. When d ∗ > 0 , the drag force plays a dominant role in the vertical force. • The laboratory experiments of ISW and slender submerged body were carried out in a stratified fluid tank. The stratified fluid tank can generate ISW with different amplitudes, and the submerged body can change different diving depths, which provides convenience for parametric classification analysis. • According to the logical analysis, two new dimensionless parameters are proposed. The analysis in this paper is based on the above dimensionless parameters, and the influence of ISW amplitude and diving depth on the force of the submerged body is discussed in detail. • It is found that the interaction time between ISW and the submerged body is a quantity related to L ∗. The vertical force curve of ISW interacting with the submerged body is related to d ∗ , and different cases are classified according to d ∗. In addition, the effects of inertia force and drag force are discussed. [ABSTRACT FROM AUTHOR]

Abstract Motivated by the taxi refusal problem in Bangkok, this paper presents a novel approach of demand-supply matching for taxi services through double auction, where passengers and drivers can offer and ask for a surcharge in addition to a regular meter fare. This system is equivalent to a variable surcharge policy as opposed to the existing fixed surcharge policy. The objective of this paper is twofold. First, we examine the design of information content for taxi service auction under two conditions: with and without time-cost. Laboratory experiments with student subjects were conducted to investigate the effect of different levels of information content on bidding strategies and market efficiency. The results show that time-cost has a significant effect on individuals' bidding strategy and market efficiency. In addition, providing bidders with greater information does not necessarily lead to better efficiency. Second, we compare the performance of the proposed method with that of the fixed surcharge policy. It is found that the variable surcharge policy outperforms the fixed surcharge policy in several aspects. In particular, the variable surcharge policy provides a better opportunity for passengers to get the taxi service and obtains a higher market efficiency at least as good as the fixed surcharge policy. Highlights • Double auction is proposed for demand-supply matching of taxi services. • Various designs of information content exposed to the bidders were investigated. • We conduct laboratory experiments to evaluate bidding strategy and market efficiency. • Providing bidders with greater information does not lead to better market efficiency. • The proposed variable surcharge policy outperforms the existing policy. [ABSTRACT FROM AUTHOR]

Disparities in breast cancer screening are often explained by socioeconomic factors, although a growing body of papers show that risk preference, time orientation and perceptions may explain mammography use. The aim of this paper is to estimate the relative contribution of socioeconomic factors, risk preference, time orientation and perceptions to disparities in breast cancer screening regularity. These determinants are elicited in an experimental laboratory from 178 women aged between 50 and 75 years in France in 2013. The results reveal that risk aversion accounts for 30% of the variance in screening regularity, which is greater than that attributable to socioeconomic determinants (20%), perceptions (11.5%) or time orientation (2%). These results suggest that further investigation on the relationship between risk aversion and screening behaviors is needed to design more comprehensive public health interventions. [ABSTRACT FROM AUTHOR]

• An experiment on voluntary disclosure of verifiable information. • Receivers are insufficiently skeptical when information is not disclosed. • Receiver naivety persists over time, despite opportunities to consult with others. • Adding a natural context (hygiene ratings) affects sender beliefs but not behavior. • Senders disclose too seldom, even allowing for receiver naivety. The unraveling prediction of disclosure theory relies on the idea that strategic forces lead firms (information senders) to voluntarily disclose information about the quality of their products provided the information disclosed is verifiable and the costs of disclosure are negligible. This theoretical prediction requires that consumers (information receivers) hold correct beliefs about non-disclosed information and, in equilibrium, treat all non-disclosed information with extreme skepticism. Previous research finds that receivers are insufficiently skeptical, or in other words are naive, about non-disclosed information, which leads to the failure of unraveling. This paper examines the extent to which naivety responds systematically to features of the decision environment, namely the availability of opportunities to communicate with others (Consultation treatment) and the context of the experimental setting (Context treatment, based on hygiene ratings). We find that complete unraveling fails to occur in all our treatments. Receiver's beliefs and guesses about non-disclosed information are similar across the Consultation and Context treatments relative to the Baseline implying that receivers are naive about non-disclosed information under naturalistic features that exist in field settings. We also find that senders are partly to blame for the lack of unraveling, as intermediate types would gain from disclosing more often given the observed receiver behavior. [ABSTRACT FROM AUTHOR]

This paper examines the impact of continuous-time interactions on the dynamics of repeated battle of the sexes games with laboratory experiments. In discrete time, players often coordinate by alternating each period between the two pure Nash equilibria. In continuous time, players can respond more quickly but must contend with a very rich strategy space and with the lack of a natural coordination device. The experiment also examines a new hybrid-time environment that runs in continuous time but offers a discrete payoff-irrelevant signal. The results suggest that the hybrid signal device greatly facilitates both coordination and alternation. Players generally tend to alternate asynchronously in continuous time, and the transitions between pure Nash equilibria are mainly driven by the "disadvantaged player". [ABSTRACT FROM AUTHOR]

Individuals often manage low and risky earnings using informal transfers, which are influenced by both fairness norms and the desire for informal risk-sharing. This paper develops an experiment that allows us to disentangle these motives when income can depend on effort. The empirical analysis shows that people are equally likely to give transfers from high-income to low-income partners when income is due to chance as when both participants exert effort to increase expected income; however, participants are less likely to give transfers when one or both partners do not exert effort. These transfers are more likely due to risk-sharing than inequity aversion. [ABSTRACT FROM AUTHOR]

In this paper, we investigate social preferences in network games, where the network structure determines whose action affects the payoff of which player. We develop alternative theories that incorporate inequality aversion and welfare preference into the context of dominant-strategy network games, and test their implications in laboratory experiments. When the economic return is relatively low, we observe that subjects contribute more than the amount that would maximize their monetary profit; moreover, subjects at the central network positions contribute more than those at the periphery. These anomalies suggest that subject behavior is mainly driven by the welfare preference and not as much by either inequality aversion or self-interest, regardless of the network structures considered. In a supplemental experiment with an increased economic return, we find that the advantage of social preferences over self-interest in driving individual activities varies with the underlying network architecture. We also estimate the behavioral parameters and interpret the results in relation to the network topology. [ABSTRACT FROM AUTHOR]

Despite the increased sophistication of numerical models and field techniques for investigating wave-induced nearshore sediment transport and ensuing beach morphological response, there remains a significant demand for large-scale laboratory experiments to address this research topic. Here, we describe the Barrier Dynamics II Experiment ( BARDEX II ), which involved placing a near prototype-scale sandy barrier in the middle of the Delta Flume in the Netherlands and subjecting the structure to a range of wave, tide, and water level conditions. A unique aspect of the experiment was the presence of a lagoon behind the barrier, as often occurs in natural barrier settings, providing a convenient means to experimentally manipulate the groundwater hydrology within the barrier. The overall aim of the BARDEX II was to collect a large-scale data set of energetic waves acting on a sandy beach/barrier system to improve our quantitative understanding and modeling capability of shallow water sediment transport processes in the inner surf, swash, and overwash zone. In this paper, we introduce BARDEX II and provide a detailed description of the experiment, including the experimental design, instrumentation, test program, and data set, as well as presenting some examples of the morphological and hydrodynamic data set. We also reflect objectively on the strengths and weaknesses of the data set. This paper serves as an introduction to a special issue of Coastal Engineering , solely devoted to the results of BARDEX II . [ABSTRACT FROM AUTHOR]

• We study gender differences in compliance behavior and perceived honesty. • Different effects of face-to-face interaction matter for women and men. • Women react to psychological effects whereas men take into account their perceived honesty. • Evidence from an honesty assessment experiment explains these differences. • Men are more likely to be assessed as dishonest irrespective of their truthfulness. In this paper, we investigate the role of face-to-face interaction with respect to gender differences in deceptive behavior and perceived honesty. In the first part, we compare the deceptive behavior of women and men using data from an incentivized income-reporting experiment with three treatments. Reporting was fully computerized in the baseline treatment but took place face to face in the second and third treatments. It was possible for lies to be detected within the scope of an audit: there was a given probability that an audit would take place in the first and second treatments, whereas the perceptions of others determined whether or not an audit would occur in the third treatment. In the computerized baseline treatment, the deceptive behavior of women and men was statistically indistinguishable. However, women's truthfulness increased when face-to-face interaction was introduced in the second treatment. In contrast, males' deceptive behavior did not change until the third treatment, when the probability of an audit taking place depended on their perceived honesty. Then, men's truthfulness rose sharply, and they behaved significantly more honestly than women, who showed no behavioral differences between the second and third treatments. In the second part we expand upon these gender differences by analyzing video recordings of income-reporting statements recorded in an experimental setting similar to the third treatment. Third parties assessed how honest they considered the recorded statements to be. Men were perceived to be less honest. Our findings suggest that men correctly anticipated that others would perceive them to be dishonest, which is consistent with the results from the first part. [ABSTRACT FROM AUTHOR]

This paper provides original empirical evidence on the emerging practice by central banks of communicating uncertainty in their inflation projections. We compare the effects of point and density projections in a learning-to-forecast laboratory experiment where participants' aggregated expectations about one- and two-period-ahead inflation influence macroeconomic dynamics. Precise point projections are more effective at managing inflation expectations. Point projections reduce disagreement and uncertainty while nudging participants to forecast rationally. Supplementing the point projection with a density forecast mutes many of these benefits. Relative to a point projection, density forecasts lead to larger forecast errors, greater uncertainty about own forecasts, and less credibility in the central bank's projections. We also explore expectation formation in individual-choice environments to understand the motives for responding to projections. Credibility in the projections is significantly lower when strategic considerations are absent, suggesting that projections are primarily effective as a coordination device. Overall, our results suggest that communicating uncertainty through density projections reduces the efficacy of inflation point projections. [ABSTRACT FROM AUTHOR]

• A group contest model with an endogenously determined prize level is tested using experiments. • Experimental data show that the proposed contest increases contributions. • Behavior in the contest with random matching is linked to intergroup comparison. • Behavior in the contest with fixed matching is linked to conditional cooperation. To mitigate free-rider problems in teamwork, this paper uses laboratory experiments to test a mechanism in which a firm creates a competitive environment for its two teams by awarding a prize based on the aggregate output produced by these two teams. The experimental results support the prediction that the proposed mechanism encourages a greater number of team members to make costly contributions. In the experimental protocol with random matching of team members across decision periods, team members are found to over-contribute relative to the theoretical prediction. This result is linked to team members' beliefs that their team has lower contributions than the competing team. In contrast, with a fixed matching protocol, team members' over-contributing is linked to conditional cooperation, based on their beliefs about the contributions of other team members. [ABSTRACT FROM AUTHOR]

The coefficient of restitution (COR) is one of the important mechanical properties of particle. The calculation model of the energetic COR of particle-particle collisions was derived. The method used to determine the energetic COR of irregular particles was proposed. Maize particle-particle collisions were simulated using the discrete element method (DEM). The kinetic energy of the particles during the collision was investigated. The relationship between the input and calculated energetic COR was obtained via simulation. The energetic COR of maize grain was obtained and verified using laboratory experiments. The results indicate that it is accurate. The results of the simulation indicate that the energetic COR is more accurate than the kinematic COR for maize grain. The effects of the impact velocity and impact angle on the energetic COR were investigated. The results of the paper will be helpful for maize grain simulation and maize-processing machine design. Unlabelled Image • The calculation model of the energetic coefficient of restitution was derived. • The kinetic energy of particle during collision was investigated. • The velocity of particle is affected by the interaction force and kinetic energy. • The energetic coefficient of restitution of maize grain was determined. • The collision period was classified based on the sliding velocity and deformation. [ABSTRACT FROM AUTHOR]

In order to solve the problem of low reliability of research results caused by the lack of simulated materials for seafloor massive sulfide (SMS) in laboratory breaking research, this paper proposes a convenient and fast preparation scheme for simulated rocks with Seafloor massive sulfide, using a mixture of cement and gypsum as the binder and natural graded river sand as the filler. At the same time, using this preparation scheme, large blocks of rock were prepared, and then standard cylindrical specimens were prepared through random sampling, core drilling, and other operations. Through density experiment, uniaxial compression experiment, and triaxial compression experiment, six physical and mechanical property parameters of the cylindrical specimen, including density, uniaxial compressive strength, elastic modulus, Poisson's ratio, cohesive force, and internal friction angle, were measured. On this basis, the feasibility and convenience of the proposed preparation method were further demonstrated through comparative analysis. The research content of this article is of great significance for the study of fragmentation experiments and the construction of deep-sea breaking theory. • A convenient and fast preparation scheme for simulated rocks with Seafloor massive sulfide is proposed. • The physical and mechanical property parameters of simulated rocks are measured by experiments. • The feasibility and convenience of the proposed preparation scheme are demonstrated through comparative analysis. [ABSTRACT FROM AUTHOR]

Abstract: Several research investigations have explored the interaction between morphodynamic and vegetation growth processes from both the modelling and the experimental viewpoints. Results have mainly been concerned with morphologic analyses of the effects of vegetation on long term riverbed evolution without addressing the relative role of the timescales between such processes. This paper presents for the first time the statistics of uprooted biomass obtained while perturbing the vegetation growing in the river bed with periodic disturbances of constant magnitude. That is, we force the biological and hydrological processes to interact and study the related timescales in order to shed light on the role of flood disturbances in selecting the component of the biomass that has a higher chance of survival in relation to its growth stage. A simple interpretative stochastic model is then presented and thoroughly discussed in a companion paper (Biomass selection by floods and related timescales: Part 2. Stochastic modelling). [Copyright &y& Elsevier]

• We use a lab experiment to analyse the role of medical liability in medical provision. • Our behavioral data show that liability pressure leads physicians to choose more care. • More care is provided regardless of patients' severity and physicians' payment system. • Medical students respond stronger to malpractice liability than non-medical students. • Payment system where liability is implemented makes the difference for social welfare. Medical liability has been suspected of increasing health expenditure insofar as it induces the practice of defensive medicine. Despite the large evidence on the role of medical malpractice liability, the identification of its causal effect on physicians' treatment decisions is a difficult task. In this paper we study for the first time in a controlled laboratory setting the effect of introducing the risk of being sued for medical malpractice on the provision of physicians' medical services. Our behavioral data show that introducing malpractice liability pressure does lead physicians to choose a higher amount of medical services, regardless of the physicians' payment system. However, we also find that the payment system in which malpractice liability is implemented makes the difference under the societal perspective, with relevant implications for health policy. [ABSTRACT FROM AUTHOR]

In this paper results of laboratory studies of damping of gravity-capillary waves due to emulsified oil films (EOF) are presented and compared to crude oil films (COF). A laboratory method based on measuring the damping coefficient and the length of parametrically generated gravity-capillary waves is applied to a 50% EOF and to crude oil films. Measurements of wave damping were carried out in a range of surface wave lengths, corresponding to Bragg waves of X- to Ka-band radars. The obtained dependences of wave damping coefficient on EOF thickness have demonstrated the existence of a damping maximum at thicknesses of about 1–2 mm, and the maximum is approximately twice the one for COF, the damping maximum for EOF is located at larger film thicknesses than for COF. Theoretical calculations of wave damping have been performed and viscoelastic parameters of EOF have been estimated from comparison between theory and experiment. • Wave damping due to oil film can have a strong maximum at certain film thickness. • Effective surface tension (EST) can have complicated zigzag dependence on film thickness. • Numerical modeling confirmed the main peculiarities of wave damping and EST. • Viscosity and elasticity of crude oil and oil emulsion films were retrieved. [ABSTRACT FROM AUTHOR]

In this paper we conducted laboratory experiment to study the spatial and temporal variation due to solitary wave collides with a vertical wall which is placed at right angle to the direction of propagation of the wave. Under various dimensionless amplitude ratios (H/h, initial wave amplitude over constant water depth), the bottom dynamic pressure, the maximum instantaneous force and the pressure on the vertical wall due to solitary wave reflecting from a vertical wall are analysed. It is interesting to note that at higher normalized amplitude (H/h>0.4), the dynamic wave pressure at the bottom and the force distribution on a vertical wall appear asymmetry double peaks, which is first shown by our experiment. From the statistical analysis, we can obtain an asymptotic formulation for the maximum instantaneous force which is proportional to the normalized amplitude ratio (H/h). Furthermore, these experimental result is used to compare with the available numerical model and theoretical solution and show a quantitative agreement. [ABSTRACT FROM AUTHOR]

In this paper we experimentally investigate the consequences of electoral fraud on voter turnout. The experiment is based on a strategic binary voting model where voters decide whether to cast a costly vote in favour of their preferred candidate or to abstain. The electoral process is illicitly influenced by applying ballot-box stuffing. In the experiment we implement two different framings: we compare voter turnout in a neutral environment and with framed instructions to explicitly replicate elections. This approach enables us to both test the model's predictions and to estimate the framing effects of voting and fraud. Comparison of experimental results with theoretical predictions reveals over-voting, which is exacerbated when fraud occurs. Turnout increases as predicted with a moderate level of fraud while, with higher levels of electoral fraud, voters fail to recognize that the existence of a relatively larger number of "agents" voting with certainty considerably decreases the benefits of voting. Importantly, framing matters, as revealed by the higher turnout of those in the majority group, against which the fraud is applied. [ABSTRACT FROM AUTHOR]

Highlights • We analyze an organ-allocation rule that gives preference to registered donors. • This priority allocation rule increases donor registration rates in lab experiments. • We vary the number of periods a person can skip on the waiting list. • A higher bonus substantially improves registration rates. • However, complete prioritization is not needed. Abstract Giving registered organ donors priority on organ waiting list can substantially increase the number of donors and save lifes. Evidence for these effects comes from recent experiments that implemented such priority rules in abstract laboratory environments. In these experiments, participants who registered as organ donors were fully prioritized over those who did not. In the field, however, registering as a donor is only one factor affecting the recipient's score. In this paper, we provide a comparative statics analysis of the priority treatment by varying the number of bonus periods that a registered person can skip on the waiting list. We find that behavior is monotonic: giving more priority to registered donors leads to higher registration rates. Our results also indicate that a medium sized bonus improves registration rates as much as absolute priority (used in the previous literature). [ABSTRACT FROM AUTHOR]

Summary: Stable water isotopes such as oxygen 18, are natural tracers of water movement within the soil–vegetation–atmosphere continuum. They provide useful information for a better understanding of evaporation and water vapor transport within soils. This paper presents a novel controlled experimental setup. It is dedicated to detailed measurements of the evaporation fluxes from bare soil columns, as well as to the corresponding isotopic composition of the water vapor, under non-steady state conditions. The experiment allowed an accurate determination of these quantities. The formulae encountered in the literature were used to estimate the isotopic composition of the evaporated water vapor. None of them was able to correctly reproduce the measured isotopic composition of water. The data were then used to estimate the value of the isotopic composition of the soil liquid water, which should be used to get the right results for the isotopic composition of the evaporated water vapor. Results suggest that, when liquid transfer is dominant within the soil, the isotopic composition of evaporation was controlled by the isotopic composition of the liquid water within very thin soil surface layers. When there is a peak in the isotopic profile, i.e. when water vapor is dominant close to the surface, the isotopic composition of the evaporated water seems to be governed by the isotopic composition of the soil liquid water at the peak. The data were also used to estimate the kinetic fractionation factor. The results suggest that the latter is not constant in time. The values seem to depend on the shape of the isotopic profile. In both cases, the uncertainty on the results is very large. The estimation of the kinetic fractionation factor is studied more in details using the modeling results presented in Part II of a companion paper where the data set is modeled using the SiSPAT_Isotope model. [Copyright &y& Elsevier]

Abstract: It is important to accurately locate the wave breaking region for the calculation of nearshore hydrodynamics. Energy from breaking waves drives hydrodynamic phenomena such as wave set-up, set-down, wave run-up, longshore currents, rip currents, and nearshore circulation. Numerous studies have been undertaken to describe when and where wave breakings occurs. Recent development of computer resources permits the use of phase-resolving numerical models for the study of wave propagation, transformation, and nearshore hydrodynamics. This requires new types of wave breaking criteria for the numerical model. The Relative Trough Froude Number (RTFN) is a new wave breaking criterion. This model is based on the moving hydraulic jump concept, therefore it satisfies properly posed boundary-value conditions. It has been experimentally proved that a critical RTFN at the initiation of wave breaking is consistent with and without the presence of an opposing current, but previous efforts did not investigate the theory for the critical value. This paper provides a theoretical analysis and a numerical analysis to demonstrate why the RTFN theory works as a wave breaking initiation (trigger) index. The theoretical analysis provides a universal constant for the initiation of wave breaking for all water depths assuming the Miche formula properly describes the wave breaking condition. A subroutine for wave breaking in a numerical model, FUNWAVE was modified to include the RTFN trigger. The numerical model was calibrated with data from wave tank experiments, and it was found that the critical condition is very close to the theoretical number, CTFN=1.45. A second paper (in preparation) provides details of the theory and experiments for a second criterion for termination of wave breaking. The time scale for the establishment of the breaking region i.e., between the initiation position and termination position, depends upon the additional momentum present under turbulent condition within the breaking wave. This subject is not considered herein. [Copyright &y& Elsevier]

Highlights • We study how preferences for agency and effective giving affect delegation of giving. • We do not find strong aversion to delegating giving. • Intermediaries requiring giving up a lot of agency only attract effective donors. • Intermediaries providing some agency only attract low effective donors. Abstract Philanthropy, and particularly ensuring that one' s giving is effective, can require substantial time and effort. One way to reduce these costs could be to encourage delegation of giving decisions to better-informed others. At the same time, because it involves a loss of agency, delegating these decisions may reduce one's charitable impulse. Unfortunately, the importance of agency in charitable decisions remains largely unexplored. In this paper we shed light on this issue using a laboratory experiment with real donations in which we systematically vary the monetary and agency costs associated with making informed and effective giving decisions,. Our main finding is that agency seems to play a small role in promoting giving. In particular, people do not reduce donations when giving decisions are made by algorithms that guarantee efficient recipients but limit donors' control over giving recipients. Moreover, we find that participating in giving groups - a weaker form of delegated giving -is also effective in that they are appealing to donors who would not otherwise make informed donations, and thus improves overall effective giving. Our results suggest that one path to promoting effective giving may be to create institutions that facilitate delegated generosity. [ABSTRACT FROM AUTHOR]

Altruistic punishment is a fundamental driver for cooperation in human interactions. In this paper, we expand our understanding of this form of pro-social behavior to help explain a puzzle of voting: why do individuals who are indifferent between two potential policy outcomes of an election participate when voting is costly? Using a simple voting experiment, we provide robust evidence that many voters are willing to engage in voting as a form of punishment, even when voting is costly and the voter has no monetary stake in the election outcome. In our sample, and in a robustness check through Monte Carlo simulation, we show that at least fourteen percent of individuals are willing to incur a cost to vote against candidates who broke their electoral promises, even when they have no pecuniary interest in the election outcome. [ABSTRACT FROM AUTHOR]

Referrals and information flow distort market mechanisms of hiring in the labor market, but they might assist employers under asymmetric information in finding better alternatives. This paper investigates whether an impartial information flow between employers in a cyclic network structure could generate more discrimination than when no information is exchanged between employers. We set up an artificial labor market in which there was no average quality difference between two categories of workers. We asked participants to play the role of employers and examined the partiality of their hiring choices. Results showed that discrimination was prevalent in all conditions. Higher standards by the employers for the quality of workers increased discrimination as did the presence of referrals from workers. Unexpectedly, impartial information flow in a cyclic network of employers did not help to decrease discrimination. We also showed that these mechanisms interact with and subdue each other in complex ways. [ABSTRACT FROM AUTHOR]

Currently, Steam-Assisted Gravity Drainage (SAGD) is the most successful commercialized method used to produce bitumen from oil sands and heavy oil reservoirs. Precise description of the steam chamber evolution is important for evaluating the economic effectiveness and Greenhouse Gas (GHG) emission of the SAGD process. In this study, the properties of MacKay River Oil Sands were used in laboratory experiments to compare the chamber evolution and production performance of SAGD under different permeability distributions. Then, a mathematical model was established to predict the steam chamber evolution and the closely related oil production and heat consumption in a heterogeneous formation. Next, the calculated production performance and steam chamber evolution were compared with measured experimental data to verify the accuracy of the model. Finally, the chamber evolution characteristics and their impacts on SAGD oil production and heat consumption are discussed in this paper for formations with different permeability distributions. The results indicate that horizontal permeability controls the evolution of steam chamber such that higher horizontal permeability may cause an obvious convex shape of the chamber edge, whereas vertical permeability has little effect on the chamber shape despite significant influence on the oil production in the early stage of SAGD. Moreover, a convex-shaped chamber interface indicates a higher production rate in the spreading stage and a lower rate in the depleting stage. In addition, this study shows that to minimize the heat consumption of the SAGD process, so that GHG emission can be curbed, a concave-like chamber shape is favorable in the early spreading stage, whereas a convex shape is better in the late spreading stage and depleting stage. [ABSTRACT FROM AUTHOR]

There is an abundance of historical and contemporary examples of consensual institutions that reduce the probability of adversarial conflicts between contesting parties. For instance, feudal lords in the medieval period supported monarchies which kept in check their mutual predatory tendencies. Contemporary nation states invest in the United Nations and NATO to contain conflicts between themselves. This paper experimentally investigates the feasibility and effectiveness of such an institution. We modify the two-agent ratio-form rent-seeking model to incorporate a pre-conflict stage in which participants voluntarily choose a level of public investment towards the establishment of the peacekeeping mechanism. A modified Tullock contest is played in the second stage, where the aggregate investment made in the first stage assists the victim in the case of a unilateral aggression. We find that the peacekeeping mechanism is effective in reducing conflict expenditures, and is least effective when the contestants initially have close but unequal endowments, as opposed to equal or widely unequal endowments. [ABSTRACT FROM AUTHOR]

Choice-based health insurance systems allow individuals to select a health plan that fits their needs. However, bounded rationality and limited attention may lead to sub-optimal insurance coverage and higher-than-expected out-of-pocket payments. In this paper, we study the impact of providing personalized information on health plan choices in a laboratory experiment. We seek to more closely mimic real-life choices by randomly providing an incentivized distraction to some individuals. We find that providing personalized information significantly improves health plan choices. The positive effect is even larger and longer-lasting if individuals are distracted from their original task. In addition to providing decision support, receiving personalized information restores the awareness of the choice setting to a level comparable to the case without distraction thus reducing inertia. Our results indicate that increasing transparency of the health insurance system and providing tailored information can help individuals to make better choices and reduce their out-of-pocket expenditures. [ABSTRACT FROM AUTHOR]

Increasing punishment is typically considered first choice to boost deterrence of unwarranted behavior such as false financial statements, asset misappropriation, stealing, or corruption. However, if there is uncertainty on a potential violator’s guilt, judges’ and juries’ willingness to impose punishment may decrease in its magnitude. Thus, increasing the magnitude of punishment may backfire, when the reduced punishment probability is anticipated by potential violators. Based on a theoretical model, our paper is the first to analyze the interdependency of violation and punishment behavior in a laboratory experiment, and to contrast it to the standard partial equilibrium perspective on deterrence that considers the punishment probability to be independent of the fine size. Varying both the magnitude of fines and the degree of uncertainty shows that, in case of legal uncertainty, the deterrent effect of higher fines is far less pronounced than if the punishment probability was exogenous. [ABSTRACT FROM AUTHOR]

Time is a crucial determinant of deception, since some misreporting opportunities come as a surprise and require an intuitive decision while others allow for extensive reflection time. To be able to pursue a deceptive strategy, however, a subject must be aware of the misreporting opportunity. This paper provides experimental evidence on the role of the time dimension for dishonest decision-making and for the cognition process of the chance to deceive. We conduct a laboratory experiment of self-serving deceptive behavior which combines two exogenously varied levels of reflection time with a cognition process about the deception opportunity. We find that time pressure leads to more honesty compared to sufficient contemplation time. More importantly, decomposing misreporting into its two components, i.e., the cognition process of the misreporting opportunity and the conscious decision to misreport, reveals that more reflection time increases awareness of the misreporting opportunity. However, more time has no effect on the conscious decision of whether to misreport or not. [ABSTRACT FROM AUTHOR]

Involving multiple-purchasers in a PES scheme has the potential to deliver numerous benefits including cost-sharing, expanded financing and broadened scope. That few such schemes exist is evidence of a classic market failure resulting from incentives to free-ride on the payments of other purchasers. In the context of an experimental investigation, this paper explores the role of negotiation and binding pre-commitments to payments in solving that collective action problem. Our novel experimental setup involves two purchasers seeking a level of payment acceptable to a single provider while also agreeing their own individual contributions to that payment. Contrasting treatments are used to explore complexities of the conditions under which negotiations might take place including asymmetries between the purchasers, treatments with incomplete information and treatments with uncertainty over the levels of benefit. We find that those complexities change the ease with which a negotiated agreement is achieved as well as the relative size of the payoffs enjoyed by the different parties to the negotiations Our findings are generally positive, showing that under many circumstances parties to a multiple-purchaser PES can successfully negotiate a mutually agreeable schedule of payments and contributions. [ABSTRACT FROM AUTHOR]

In an age of unprecedented decline in global biodiversity levels, the task of designing laws that effectively protect nature and biodiversity is urgent. To help address this enforcement deficit, European policymakers have sought to democratise environmental enforcement by conferring citizens and environmental nongovernmental organisations (NGOs) with legal rights of access to environmental information, public participation and access to justice in environmental matters, derived from an international treaty known as the UNECE Aarhus Convention (the so-called "Aarhus mechanisms"). However, there has been little systematic empirical research to date on the effectiveness of this new wave of private nature governance laws, and their impacts on compliance decisions. This paper seeks to address this gap. We investigate, by means of a laboratory experiment with student participants, the extent to which different nature governance rules affect individuals' decisions to comply. By nature governance rules, we mean the legal tools used to promote compliance with nature conservation rules, including traditional governance rules such as criminal penalties and civil fines, but also the new generation of private governance rules, in the form of the Aarhus mechanisms. Our findings provide new empirical experimental confirmation that traditional and private environmental governance rules together achieve more effective nature conservation outcomes than traditional governance rules alone. They also suggest, however, that private governance rules may lead to some duplication of enforcement effort by the State and citizens. [ABSTRACT FROM AUTHOR]

• Intergroup competition will divide individuals into high-status groups and low-status groups. • We conduct a laboratory experiment to find how group status changes cooperation in two representative social dilemma frameworks. • Both the high-status and low-status group members will improve ingroup cooperation. • The framing effect of cooperation will affect different status group members' cooperation behavior. Intergroup competition has been proven to increase ingroup cooperation, but it will also divide individuals into high-status groups and low-status groups, which may lead to group-level conflict and affect cooperation behavior among different status group members. In this paper, we conduct a laboratory experiment to find how group status caused by intergroup competition changes individuals' cooperation behavior in two representative social dilemma frameworks, the public goods game and the prisoner's dilemma game. Experimental results show that both high-status group members and low-status group members will improve ingroup cooperation, and there exists the framing effect of cooperation which affects different status group members' decisions under different situations. Specifically, the increase of ingroup cooperation occurs among low-status group members in the public goods game and high-status group members in the prisoner's dilemma game. Besides, we find no evidence of any significant change in outgroup cooperation among different status group members. [ABSTRACT FROM AUTHOR]

In this paper, we propose a pulsed flow control of the radiant system with a fixed on-time to replace the storage water in pipes and a variable off-time to regulate the capacity. We developed a three-dimension numerical model to simulate the performance of the radiant heating and cooling system in the pulsed flow control method. Through numerical simulation on radiant systems with various thermal masses, the average supply and return water temperature difference and surface temperature non-uniformity were compared between the pulsed flow control and the variable flow rate control. The results demonstrate that the pulsed flow control achieves a comparable supply and return water temperature difference and pump energy consumption to the variable flow rate control. However, the pulsed flow control method saves the initial cost by substituting proportional valves by two-way position valves and has a higher controllability in part load. Furthermore, the pulsed flow control yields a smaller surface temperature non-uniformity than variable flow rate control, which is beneficial to reduce the condensation risk in cooling condition. [ABSTRACT FROM AUTHOR]

This paper studies how participation in decision procedures affects people’s reactions to the deciding authority. In our economic experiment, having voice, i.e., the opportunity to state one’s opinion prior to a decision, significantly increases subordinates’ subsequent kindness towards the authority. These positive effects occur irrespectively of the decisions’ content. The experimental findings stress the positive effects of voice when subordinates and authorities interact. Our results suggest that in organizations, but also in the legal and political arena, participative decision-making can be used to guide people’s actions after decisions have been made. [ABSTRACT FROM AUTHOR]

Erosion of drill pipe caused by the rock particles in annular space is very serious in gas drilling. The aim of this paper is to study the erosion wear law of drill pipe by theoretical derivation and laboratory experiment. Based on the micro-cutting model of single rock particle, the erosion model of drill pipe is established to calculate the erosion wear loss. This model establishes the relationship between the erosion wear loss of drill pipe and drilling parameters, such as gas injection volume and rate of penetration (ROP). The laboratory experiment is carried out to verify and revise the erosion model, and the results show that when ROP is less than 20 m/h, the erosion wear loss of drill pipe is approximatively proportional to the square of gas injection volume and has positive correlation with ROP. However, it has negative correlation with ROP when ROP is faster than 20 m/h. In addition, it is also obtained that gas injection volume has more impact on drill pipe erosion compared to ROP based on the analysis of an engineering example, and high ROP will suppress the erosion wear of drill pipe. Therefore, under the premise of satisfying the drilling requirements, employing lower gas injection volume and higher ROP can reduce drill pipe erosion in gas drilling, which will save the drilling cost greatly. [ABSTRACT FROM AUTHOR]

The paper presents a seismic data interpretation approach to reconstruction of stress fields in rocks at any stage of coal mining. The approach involves: thee-axial compression testing of coal in order to find an empirical relation between elastic wave velocity and stresses; coal bed tomography using standard monitoring systems and taking signals generated by dynamic events (with the energy higher than the background level) as the probing signals; formulation and solving of a boundary inverse problem within a geomechanical model of an object under analysis where the input data is the velocity field reconstructed in the illuminated area of coal bed by tomography. The laboratory data of the coal specimens tested by the von Karman scheme have been approximated to plot analytical relationships between P-waves velocity, axial stress and confining pressure. The numerical experiments performed for a typical underground layout at coal producer “Vorkutaugol” have shown that given the accepted array of seismic pickups, the single-valued solution of the inverse problem requires good illumination of coal bed areas with the spatial stress gradient. [ABSTRACT FROM AUTHOR]

• This paper outlines the significant effects of the pipe-soil interactions on pipeline walking. • A set of large-scale model tests are conducted on the axial soil resistances of pipelines placed on Bohai sand. • Based on the test results and the influence mechanisms of the pipe-soil interactions on pipeline walking, a bi-linear pipe-soil interaction model for pipelines placed on sandy soils is proposed. • This paper presents an alternative method for the identification of pipe-soil interaction during pipeline-walking analysis for a certain site-specific soil. Pipeline walking induced by heat-up and cool-down cyclic loadings during shutdown and restart cycles is a challenge in the design of relatively short pipelines exposed on seabeds. A major source of uncertainty in the analysis of pipeline walking is the pipe-soil response, which has a significant influence on pipeline walking. To investigate the pipe-soil response during pipeline walking, a set of large-scale model tests are conducted on Bohai sand, and they involve axially moving pipelines with different speeds and cycles. Based on these test results, bi-linear pipe-soil interaction models with normalization of the pipe weight and diameter are proposed for Bohai Bay sand. Subsequently, a comparison of the model test data to existing pipe-soil interaction models is performed, and the existing pipe-soil interaction models are calibrated with site-specific soil properties of Bohai Bay sand. Finally, the application of the site-specific pipe-soil interaction models for a pipeline-walking analysis of pipeline placed on Bohai Bay sand is performed with the finite element method to study how pipeline walking is influenced by these pipe-soil interaction models. Combined with the influence mechanisms, a design model is proposed that considers the potential risks of pipeline walking in pipeline design to reduce costs without compromising reliability. [ABSTRACT FROM AUTHOR]

An urban flood is an integrated phenomenon that is affected by various uncertainty sources such as input forcing, model parameters, complex geometry, and exchanges of flow among different domains in surfaces and subsurfaces. Despite considerable advances in urban flood modeling techniques, limited knowledge is currently available with regard to the impact of dynamic interaction among different flow domains on urban floods. In this paper, an ensemble method for urban flood modeling is presented to consider the parameter uncertainty of interaction models among a manhole, a sewer pipe, and surface flow. Laboratory-scale experiments on urban flood and inundation are performed under various flow conditions to investigate the parameter uncertainty of interaction models. The results show that ensemble simulation using interaction models based on weir and orifice formulas reproduces experimental data with high accuracy and detects the identifiability of model parameters. Among interaction-related parameters, the parameters of the sewer–manhole interaction show lower uncertainty than those of the sewer–surface interaction. Experimental data obtained under unsteady-state conditions are more informative than those obtained under steady-state conditions to assess the parameter uncertainty of interaction models. Although the optimal parameters vary according to the flow conditions, the difference is marginal. Simulation results also confirm the capability of the interaction models and the potential of the ensemble-based approaches to facilitate urban flood simulation. [ABSTRACT FROM AUTHOR]

In the adaptive comfort model thermal comfort is described as being influenced by physiological, behavioural and psychological adaptive processes. As psychological variables expectation and habitual adaptation are mentioned. However, the psychological aspects are not sufficiently described yet and related to psychological states rather than personality traits. In this paper, the application of a new questionnaire concerning perceived self-efficacy in the thermal environment is demonstrated. Perceived self-efficacy is in this case the expectation to be able to execute desired actions with respect to the control of indoor thermal conditions. The construct thermo-specific self-efficacy (specSE) was used to analyse differences in the perception of thermal comfort, assumed temperature, perceived control and physiological parameters. Data from field studies in office buildings were compared with data from laboratory experiments. Results showed an influence of specSE on thermal comfort, e.g. people with a low level of specSE feel warmer than people with high specSE. Also perceived control and effectiveness of controls differs between people with high and low specSE. [ABSTRACT FROM AUTHOR]

• Unique test setup to measure soil thermal conductivity at a specified stress level. • Steady- and transient-state soil thermal conductivity measurements from a single test. • Steady-state soil thermal conductivity is higher than that at transient-state. • Rate of soil temperature increment influences transient-state thermal conductivity. • Thermal conductivity of saturated clays correlates well with geotechnical properties. Precise estimation of soil thermal conductivity is crucial for reliable heat flow analysis in soil. Research indicates variations in soil thermal conductivity values estimated using transient- and steady-state temperature measurements. However, sources of such reported differences cannot be specified with certainty. This paper presents the development of a soil thermal conductivity measurement device that enables simulation of a specified stress condition on soil specimens and estimation of both transient- and steady-state soil thermal conductivity values from different segments of a single test. A series of thermal conductivity tests were performed on seven different soils using the specially-designed test setup. The difference in soil thermal conductivity values obtained from transient- and steady-state responses are compared to those reported in the literature. In contrast to steady-state soil thermal conductivity, results indicate an increase in transient-state soil thermal conductivity beyond a threshold value of the rate of soil temperature increment during the transient-state measurement. Furthermore, empirical relations are suggested to correlate soil thermal conductivity of fine-grained soils with plasticity index, hydraulic conductivity, and coefficient of consolidation. [ABSTRACT FROM AUTHOR]

A salt gradient solar pond with porous medium bed has been paid more and more attention, due to potential positive effect of porous medium on the thermal performance of salt gradient solar pond and also the delay action salt diffusion. Stability of salt gradient solar pond depends on the maintenance of the salt gradient. In this paper the effect of the porosity porous material on the salinity diffusion under the constant Lower Convective Zone (LCZ) temperature is experimentally studied, and the cleaned and screened coal cinder was used as the adding porous material. Under the same salt gradient conditions, the salinity development of LCZ with porous medium layer with porosity of 61%, 65.5%, 67% and 74% is respectively studied, the blank experiment without adding any porous material was used for comparison, and according to the experimental data, the salt diffusion coefficient in each depth was calculated by numerical method. Experimental results show that within the experimental temperature range, the porous medium can delay the salt diffusion upward. Some signs show that the porous material seems to have the absorption effect on salt. The smaller porosity the porous medium is the more slowly salt diffuses. [ABSTRACT FROM AUTHOR]

The Japanese coastal areas have a lot of different types of coastal structures with different purposes, and it is important to understand each structure's effects on tsunami. In the present paper, the authors focused on detached breakwaters effects on tsunami flow around coastal dykes with a field data investigation and laboratory experiments using a tsunami basin. The field data obtained from the 2011 Tohoku Earthquake and Tsunami showed that tsunami flow was not uniform along a coastal dyke with the specific arrangement of detached breakwaters. The laboratory experiments performed in a tsunami basin showed that a detached breakwater with a small detached breakwater parameter (distance from the shoreline/length of the opening)had a tsunami mitigation effect along the shoreline just behind the main body of the breakwater, but did not have a tsunami mitigation effect along the shoreline just behind the opening. The results obtained from the laboratory experiments agreed with the field data of the 2011 tsunami. [ABSTRACT FROM AUTHOR]

This paper presents a laboratory experiment to investigate how social motivations and free-form communication (Rich Communication) can facilitate coordinated resistance against divide-and-conquer transgressions. In our experiment, a leader first decides whether to extract surplus from a victim and shares it with a beneficiary . We find that the successful joint resistance rate increases almost four-fold (from 15 to 58%) when moving from more restrictive communication treatments to Rich Communication. We also find that the significant impacts of Rich Communication are driven more by the responders' ability to send free-form messages rather than the multiple and iterative opportunities to indicate intentions. [ABSTRACT FROM AUTHOR]

Acoustic sensors are frequently used to measure aeolian saltation. Different approaches are used to process the signals from these instruments. The goal of this paper is to describe and discuss a method to measure aeolian saltation with acoustic sensors. In a laboratory experiment, we measured the output from an advanced signal processing scheme on the circuit board of the saltiphone. We use a software implementation of this processing scheme to re-analyse data from four miniphones obtained during a field experiment. It is shown that a set of filters remove background noise outside the frequency spectrum of aeolian saltation (at 8 kHz), whereas signals within this frequency spectrum are amplified. The resulting analogue signal is a proxy of the energy. Using an AC pulse convertor, this signal can be converted into a digital and analogue count signal or an analogue energy signal, using a rectifier and integrator. Spatio-temporal correlation between field deployed miniphones increases by using longer integration times for signal processing. To quantify aeolian grain impact, it is suggested to use the analogue energy output, as this mode is able to detect changes in frequency and amplitude. The analogue and digital count signals are able to detect an increase in frequency, but are not able to detect an increase in signal amplitude. We propose a two-stage calibration scheme consisting of (1) a factory calibration, to set the frequency spectrum of the sensor and (2) a standardized drop-test conducted before and after the experiment to evaluate the response of the sensor. [ABSTRACT FROM AUTHOR]

Floating aquaculture cages deployed in the nearshore affect the wave field and contribute to the coastal defense by damping incoming waves. Most pioneering works concerning aquaculture cages have concentrated on the hydrodynamics of the structures instead of their influence on the wave field. In order to bridge the gap, this paper examines the wave performance with the interference of floating aquaculture cages via physical model tests. The results show that the existence of cages increases wave height on the weather side. The wave-dissipation performance of the net cage is closely related to the ratio of the wavelength to the structural span, and the minimum transmission coefficients appear in the conditions with the maximum wave number. Moreover, the crests of the free surface elevation inside the floating frames are almost flat, which is particularly obvious in the long-period wave conditions. The surface elevations show nonlinearity in small-wavelength conditions, which is dominantly caused by the pitch motion of the cages. Nevertheless, the presence of the cage does not affect the phase differences in the wave elevation at different positions. The nets have an opposite effect on wave response inside the cage under the conditions of long-period and short-period waves. • The wave performance with the interference of floating aquaculture cages are examined via physical experiments. • The wave transmission coefficients were closely related to the ratio of the wavelength to the structural span. • The wave surface elevations inside the floating frames showed nonlinearity under small wavelengths. • The nets had an opposite effect on the wave response inside the floating frame in long- and short-period waves. [ABSTRACT FROM AUTHOR]

Abstract: Other-regarding motivation is a fundamental determinant of public service provision. In health care, one example is physicians who act benevolently towards their patients when providing medical services. Such patient-regarding motivation seems closely associated with a personal sacrifice that health service providers are willing to make. Surprisingly, evidence on physicians' motivation is rare. This paper contributes to the literature by investigating prospective physicians', in particular, medical students', motivations and behavior. We measure the willingness to sacrifice own profit in order to increase the patients' health benefit. We conduct the same analysis for non-medical students. In a controlled incentivized laboratory experiment, participants decide, in the role of physicians, on the provision of medical services under fee-for-service or capitation schemes. Overall, 42 medical students and 44 non-medical students participated in five experimental sessions conducted between 2006 and 2008. We find substantial differences under both payment systems: compared to medical students, students of non-medical majors are less patient-regarding, less willing to sacrifice their own profit, and they state less motivation to improve patients' health. This results in significantly lower patient health benefits. Some implications for health care policies in light of physician shortage and for physician payment systems are discussed. [Copyright &y& Elsevier]