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We conducted a field experiment in a Dutch retail chain of 122 stores to study the interaction between team incentives, team social cohesion, and team performance. Theory predicts that the effect of team incentives on team performance increases with the team’s social cohesion because social cohesion reduces free-riding behavior. In addition, team incentives may lead to more coworker support or to higher peer pressure and thereby, can affect the team’s social cohesion. We introduced short-term team incentives in a randomly selected subset of stores and measured for all stores, both before and after the intervention, the team’s sales performance and the team’s social cohesion as well as coworker support and peer pressure. The average treatment effect of the team incentive on sales is 1.5 percentage points, which does not differ significantly from zero. In line with theory, the estimated treatment effect increases with social cohesion as measured before the intervention. Social cohesion itself is not affected by the team incentives. This paper was accepted by Yan Chen, decision analysis.

A study was carried out to test the effect of antagonistic fungal strains in combination with liquid material (biochemical formulation) to suppress the effect of V. dahliae. Among the five antagonistic fungal strains, most significant biocontrol efficacy has been recorded in A. terreus followed by T. harzianum under natural field conditions. The most effective biocontrol efficacy has been observed in combinatorial study between biochemical formulation prepared from the extractof Ricinus communis, Tinospora cardifolia, Withania. Somniferawith copper sulphateand T. harzianum under natural field conditions. Effect of antagonistic strains helps to increases height and cotton yield as compared to control plants. This investigation indicates that fungal strains in combination with biochemical formulation have the potential to control Verticillium wilt in significant proportion and recommendation for the usage of biochemical formulation during cotton cultivation.

This study uses a large field experiment linked to actual behavior to evaluate the effects of an information campaign with and without celebrity endorsement on the use of single-use plastics. We find that demand for single use plastics, particularly for plastic straws and spoons, is very responsive to information when — and only when — it is coupled with our celebrity endorsement. The effect of celebrity endorsement is sizeable. Subjects in the treatment with celebrity endorsement use around 29% fewer plastic straws and spoons in the shop at the end of the experiment compared with subjects in the control group. The impact of our one-shot intervention goes beyond the immediate effect measured right after the intervention. It remains significant and similar in size around one month after the intervention. Exploratory analysis suggests that an isolated information campaign affects attitudes, but not behavior, and that it is the celebrity endorsement itself that affects behavior.

Understanding how patterns of host-seeking behaviour differ across demographic classes in Amblyomma americanum (L.), the lone star tick, is essential in evaluating species potential as a vector of pathogens. Our objective was to characterize the relative contributions of two cryptic developmental cohorts, newly moulted and overwintered adults, to the A. americanum host-seeking population. To determine cohort identity, we used haem concentration as a metric of physiological age in ticks collected from field and forest habitats. Emergence of ticks displaying uncharacteristically high haem concentrations in late spring and early summer would indicate that newly moulted adults resume questing activity in the same season of their nymphal engorgement. Overall, haem concentration decreased significantly throughout the active season of adults from March to July of 2017 in northeast Missouri. Males displayed higher average haem concentrations than females when controlled for date of capture, but habitat-mediated differences were not significant. No subset of ticks with inflated haem concentrations was collected during the time that activization of newly moulted adults was feasible, suggesting that A. americanum adults undergo post-moulting behavioural diapause under natural conditions.

All animals carry specialized microbiomes, and their gut microbiota are continuously released into the environment through excretion of waste. Here we propose the meta-gut as a novel conceptual framework that addresses the ability of the gut microbiome released from an animal to function outside the host and alter biogeochemical processes mediated by microbes. We demonstrate this dynamic in the hippopotamus (hippo) and the pools they inhabit. We used natural field gradients and experimental approaches to examine fecal and pool water microbial communities and aquatic biogeochemistry across a range of hippo inputs. Sequencing using 16S RNA methods revealed community coalescence between hippo gut microbiomes and the active microbial communities in hippo pools that received high inputs of hippo feces. The shared microbiome between the hippo gut and the waters into which they excrete constitutes a meta-gut system that could influence the biogeochemistry of recipient ecosystems and provide a reservoir of gut microbiomes that could influence other hosts. We propose that meta-gut dynamics may also occur where other animal species congregate in high densities, particularly in aquatic environments.

Status and reputation concerns are conjectured to be important especially in markets with information asymmetries between buyers and sellers, such as in credence goods markets. To investigate the effects of status and reputation on reciprocal behavior of sales personnel in a financial credence goods market, we run a natural field experiment. We send e-mail requests to insurance brokers asking for an appointment. We find that status nudging and, with a larger effect size, reputation nudging in the e-mails increase brokers’ response rates compared to a neutral request. Both effects are robust across all responses, only counting affirmative responses, and in urban and rural areas.

As promises are non-binding, they can be either fulfilled or broken. Previous lab and field research mostly examines the factors that explain fulfillment, as promising itself is difficult to randomly assign. We design a novel natural field experiment where subtle changes of words in an invitation email shifts the level of promise making among our subjects to test the causal effect of promises. Promises are positively related to experimental attendance, and using the invitation treatment as an instrumental variable, we recover a positive but imprecisely measured causal impact of promise making on behavior.

For security reasons, employees of a Dutch local government department needed to wear an identifying lanyard with their employee badge, but compliance with this policy was low. Two nudges to increase compliance were evaluated in a pre-registered natural field experiment using a pre-post design, and a qualitative survey. Bayesian inference provides insufficient support for the effectiveness of the nudges. While more respondents judged the nudges and the lanyard policy positively than negatively, there was substantial negative judgment and incomprehension for both with some employees finding the nudges paternalistic. We hypothesize that the nudges were ineffective because they failed to change attitudes about the policy, and because they led to reactance among some employees. Implications for nudging within organizations are discussed.

We study the impact of deterrence, tax morale, and simplifying information on tax compliance. We ran five experiments spanning the tax process which varied the communication of the tax administration with all income taxpayers in Belgium. A consistent picture emerges across experiments: (i) simplifying communication increases compliance, (ii) deterrence messages have an additional positive effect, (iii) invoking tax morale is not effective. Even tax morale messages that improve knowledge and appreciation of public services do not raise compliance. In fact, heterogeneity analysis with causal forests shows that tax morale treatments backfire for most taxpayers. In contrast, simplification has large positive effects on compliance, which diminish over time due to follow-up enforcement. A discontinuity in enforcement intensity, combined with the experimental variation, allows us to compare simplification with standard en-forcement measures. Simplification is far more cost-effective, allowing for substantial savings on enforcement costs, and also improves compliance in the next tax cycle.

The mission of a job affects the type of worker attracted to an organization but may also provide incentives to an existing workforce. We conducted a natural field experiment with 246 short-term workers. We randomly allocated some of these workers to either a prosocial or a commercial job. Our data suggest that the mission of a job has a performance-enhancing motivational impact on particular individuals only, those with a prosocial attitude. However, the mission is very important if it has been actively selected. Those workers who have chosen to contribute to a social cause outperform the ones randomly assigned to the same job by about half a standard deviation. This effect seems to be a universal phenomenon that is not driven by information about the alternative job, the choice itself, or a particular subgroup.

We partnered with Alaska's Pick.Click.Give. programme to implement a statewide natural field experiment with 540,000 Alaskans designed to examine two of the main motivations for charitable giving: concerns for the benefits to self (impure altruism or 'warm glow') or concerns for the benefits to others (pure altruism). Our empirical results highlight the relative importance of appeals to self: individuals who received such an appeal were 6.6% more likely to give and gave 23% more than counterparts in the control group. Yet, a message that instead appealed to recipient benefits (motivated by altruism) had no statistically significant effect on average donations relative to the control group. We also find evidence of long-run effects of warm-glow appeals in the subsequent year. Our results have import for theoreticians and empiricists interested in modelling charitable giving as well as practitioners and policymakers.

In this paper, we show that the right to determine the sequence of moves in a dynamic team tournament improves the chances of winning the contest. Because studying dynamic team tournaments – like R&D races – with interim feedback is difficult with company data, we examine decisions of highly paid professionals in soccer penalty shootouts and show that teams whose captains can decide about the shooting sequence are more likely to win the shootout. So, managerial decisions matter for outcomes of dynamic tournaments and we discuss potential reasons for this finding.

We evaluate both a natural field experiment and quasi-experimental variation in commute times for a shared transportation service provided by a large technology company during morning and a...

We study the division of trade surplus in a competitive market environment by conducting a natural field experiment on German eBay. Acting as a seller, we offer Amazon gift cards with face values of up to 500 Euro. Randomly arriving buyers, the subjects of our experiment, make price offers according to eBay rules. Using a novel decomposition method, we infer offered shares of trade surplus and find that the average share proposed to the seller amounts to 29%. Additionally, we document: (i) insignificant effects of stake size; (ii) poor use of strategically relevant public information; and (iii) behavioural differences between East and West German subjects.

This paper uses a natural field experiment to connect corporate social responsibility (CSR) to an important but often neglected behavior: employee misconduct and shirking. Through employing more than 1,500 workers, we find that our use of CSR increases employee misbehavior—24% more employees act detrimentally toward our firm by shirking on their primary job duties when we introduce CSR. Observed data patterns across the treatments are consonant with a model of “moral licensing,” whereby the “doing good” nature of CSR induces workers to misbehave on another dimension that is harmful to the firm. This paper was accepted by Yan Chen, decision analysis.

Mosquito control in Cameroon relies largely on the proper use of Long-Lasting Insecticidal Nets (LLINs). It is necessary to monitor their effectiveness in order to propose corrective measures to improve the strategy. The aim of this work was to determine the physical integrity and effectiveness of LLINs (Interceptor brand) on Anopheles gambiae s.l. populations in two urban and rural areas of the Ayos health district. The level of LLIN coverage and use was assessed through a population survey. The physical integrity of LLINs was assessed by measuring the holes according to the WHO method. Bio-efficacy testing of ITNs was carried out according to the cone test protocol using 2-5-day-old, non-blood fed Anopheles gambiae s.l. females from the natural field strain and the reference susceptible strain. Household LLIN coverage rates in urban and rural areas were 55.50% and 66.94%, respectively. On the other hand, the rates of use were 78.01% and 75.22% in urban and rural areas respectively. The proportion of nets that had lost their physical integrity after 36 months of use was 47.00% and 59.63% in urban and rural areas respectively. The size of holes ranged from 0.5 to 25 cm. Alphacypermethrin was found to be ineffective against both strains of Anopheles gambiae s.l. tested. Knockdown rates ranged from 8.5% to 73% for the reference susceptible strain and less than 2.5% for the natural field strain. Mortality rates for the natural strain of Anopheles gambiae s.l. ranged from 0% to 2.5% while they were between 29% and 70% for the susceptible strain. The results show a decrease in the effectiveness of LLINs against the mosquitoes tested. This may be due to the lower than expected WHO possession and use rates of LLINs, their relatively high degree of wear and tear, and the resistance of the vectors to alphacypermethrin.

Although volunteers are a critical resource for non-profit organizations, little is known about how best to motivate them to work. A non-profit organization asked episodic volunteers to produce handmade greeting cards to sell at a fundraising event. By running a natural field experiment, we study the effect of motivating these volunteers through (a) the opportunity to vote on how the money that was raised would be spent and (b) the prospect of individual performance feedback. We find an economically and statistically significant positive effect of both tools on the quantity of work done, while the quality is mostly unaffected. Moreover, we observe significant gender differences in responsiveness to the treatments. While the prospect for feedback is more motivating to men, women respond more strongly to the opportunity to decide how the money would be spent. Empowerment seems to be a simple way to increase engagement for people with low enjoyment.

Firms typically treat their costs as tightly-guarded secrets. In six studies, we test the effect of firm disclosure of the costs to produce a given product (i.e., cost transparency) on purchase interest. We begin with a natural field experiment conducted with an online retailer, in which cost transparency increased sales (Study 1A). We subsequently replicate this field experiment in a controlled lab setting (Study 1B), and show that cost transparency is particularly potent in boosting purchase interest above other forms of transparency (Study 2). Guided by our theoretical framework, Studies 3 and 4 show that the effect is mediated by consumers’ trust in the firm, with Study 4 showing that this mediator explains variance above and beyond perceptions of price fairness. Finally, Study 5 demonstrates the critical role of the voluntary nature of the disclosure, by showing that cost transparency boosts purchase interest only when voluntarily instated by the firm, as opposed to involuntarily (e.g., as required by law). These results imply that the proactive revelation of costs can improve a firm’s bottom line.

We present a natural field experiment designed to measure other-regarding preferences in the market for taxis. We employed testers of varying ethnicity to take a number of predetermined taxi journeys. In each case, we endowed them with only 80% of the expected fare. Testers revealed the amount they could afford to pay to the driver midjourney and asked for a portion of the journey for free. In a 2 × 2 between-subjects design, we vary the length of the journey and whether a business card is elicited. We find that (1) the majority of drivers give at least part of the journey for free, (2) giving is proportional to the length of the journey, and (3) 27% of drivers complete the journey. Evidence of outgroup negativity against black testers is also reported. In order to link our empirical analysis to behavioral theory, we estimate the parameters of a number of utility functions. The data and the structural analysis lend support to the quantitative predictions of experiments that measure other-regarding preferences, and they shed further light on how discrimination can manifest itself within our preferences. This paper was accepted by Yan Chen, behavioral economics.

The study was conducted in the period 2017-2019 in the experimental fields of the Institute of Plant Genetic Resources "K. Malkov” in Sadovo, near Plovdiv, Bulgaria. At the infectious area, the immune responses of twenty-two genotypes of common winter wheat to the causative agent of brown leaf rust - Puccinia recondita f. sp. Tritici were tested The line MX 289/2048 has shown high resistance to the pathogen, and seven samples are characterized by a stable reaction. The biggest share of the studied breeding materials showed average resistance to the phytopathogen. A comparison of the indicators of grain weight in the central spike and 1000 kernel weight was made for samples grown on an infectious site and under natural field conditions. The obtained results showed an exceeding the values of the trait in favor of the samples grown under natural field conditions. It was found that the greatest influence on the traits grainsweight in the central spike and 1000 kernels weight has the year of cultivation. To assess the genetic diversity, a cluster analysis was applied, in which the selection materials were grouped into five main cluster groups. The lines MX 286/1777 and MX 270/3461 are characterized by the greatest genetic proximity, and the line MX 285/1058 is genetically the most distant compared to the samples from the first cluster group.

The retail chains in Poland has been undergoing constant structural, quantitative and qualitative changes since the beginning of transformation. New formats, such as parks and shopping malls, are appearing in the structure of the retail chains, there is an intensive development of discount chains, applying the low-price strategy and selection of the assortment offer. Traditional, small stores more and more often operate within integrated chains, which allow them to reduce operating costs. E-commerce and new technologies supporting distribution processes are essential for the development of the retail chains. The situation changes most quickly in largest cities, but over time, similar changes also take place in small towns and rural areas. Large and medium-sized cities, as attractive markets, were a natural field for increased activity of commercial investments. For several years, investors have started to expand into small towns, which constitute 76% of cities in Poland. The aim of the article is to determine the impact of retail chains, especially discount chains, on the development of small towns and the surrounding rural areas. In 2018, pilot studies were carried out in selected small towns and rural areas in the Śląskie Voivodeship, located in the zone of influence of the Upper Silesian agglomeration. Sieć handlu detalicznego w Polsce od początku transformacji ulega ciągłym zmianom strukturalnym, ilościowym oraz jakościowym. W strukturze sieci detalicznej pojawiają się nowe formaty handlu wielkopowierzchniowego, takie jak parki i galerie handlowe, obserwowany jest intensywny rozwój sieci dyskontowych, stosujących strategię niskich cen oraz selekcję oferty asortymentowej. Tradycyjne, małe sklepy coraz częściej działają w ramach sieci zintegrowanych, które pozwalają im na redukcję kosztów funkcjonowania. Istotne znaczenie dla rozwoju sieci detalicznej ma handel elektroniczny i nowe technologie wspierające procesy dystrybucyjne. Sytuacja zmienia się najszybciej w dużych ośrodkach miejskich, ale z czasem analogiczne zmiany zachodzą też w małych miastach i na obszarach wiejskich. Duże i średniej wielkości miasta, jako atrakcyjne rynki zbytu, były naturalnym polem dla wzmożonej aktywności inwestycji handlowych. Od kilku lat inwestorzy rozpoczęli ekspansję do małych miast, które stanowią 76% liczby miast ogółem w Polsce. Celem artykułu jest określenie wpływu detalicznych sieci handlowych, w szczególności dyskontowych, na rozwój małych miast oraz otaczających je obszarów wiejskich. W 2018 r. przeprowadzono badania pilotażowe w wybranych małych miastach i na obszarach wiejskich w województwie śląskim, położonych w strefie oddziaływania aglomeracji górnośląskiej. Do badań zakwalifikowano małe miasta, w których funkcjonują sieci dyskontowe. Dla pełniejszej oceny oddziaływania handlu sieciowego na rozwój lokalny zinwentaryzowano rozmieszczenie placówek handlowych w badanych jednostkach.

An increasing interest in biochar application has opened many multidisciplinary research areas in science. Biochar can be produced by thermochemical conversion of organic biomass in an oxygen-deficient condition. Extensive research has been conducted on the potential of biochar for agronomic applications, such as soil fertility improvement and carbon sequestration due to its specific mineralogical composition and long-term stability in the soil. Using biochar for environmental remediation has also been recognized recently as a promising area of research for its unique physicochemical characteristics, redox potential, and adsorption capacity. However, the published works are mostly focused only on the agronomic and environmental applications with little information presented to elucidate the different mechanisms involved. This study, therefore, aims to examine the influence of controlling parameters during biochar production, such as pyrolysis temperature, residence time, and types of feedstock on the characteristics of biochar. Various mechanisms explaining the potential of biochar for the environmental and agronomic applications are discussed in detail. The challenges faced in biochar development and its field applications for agronomic and environmental remediation purposes are also highlighted. Finally, recommendations for future research are given on the development of biochar with high redox functional groups and sorption potential as well as on understanding the behavior of biochar under the natural field conditions.

Resume studies are natural field experiments in which researchers standardize the content of resumes and vary them by individual characteristics. Researchers submit the resumes to job advertisements and compare the employers' responses toward the different resumes to measure labor market discrimination. Despite the robustness of this method, its use has not been fully exploited in human resource management and organizational psychology research. Based on a literature review, we provide an overview of the best practices for resume studies and a step‐by‐step plan to guide researchers. We also explain challenges in the design and implementation of these studies and how they can be addressed. Finally, we suggest avenues for future research and how future studies can contribute to reduce hiring discrimination.

Relevance and methods. The information on the influence of samples of chickpea sorts, time of planting the lines of chickpeas on seed infection with ascochytosis and on the weight of grain on one plant bush is presented in this article. Samples of chickpea sorts and lines were studied during the first sowing period — the first decade of March and the second sowing period — the third decade of March. Ascochytosis infection was evaluated in natural field conditions. The study was conducted at the Central Experimental Station of the Galaaral Research Institute of Grain and Leguminous Crops in 2015–2017 in Uzbekistan.Results. According to the three-year study, it was found that in the years when there was a lot of precipitation days, sorts Yulduz, ILC 263 and MП 2015/1 of the lines during the first sowing were determined to be infected with acochytosis up to 6 points. During the first sowing period of this cv., there was a decrease in the weight of grains on one plant bush compared to the second sowing period. Cv. ILC 3279, Umid and line 14442 were found to be virtually undamaged in natural field conditions with ascohitosis during both planting periods. It wasfound our that the weight of cv. Мustaqillik-20, line 14442 grain on one plant bush remained high during both planting periods.

Seventeen genotypes of spine gourd were screened against cucurbit fruit fly (Bactrocera cucurbitae) under natural field conditions with the collaboration of AICRP Potential Crop at Research-cum-Instructional Farm of IGKV, RMD College of Agriculture and Research Station Ambikapur in northern hilly region of Chhattisgarh during kharif 2017-18. Among the all, none of genotype was performed free from fruit fly infestation. Only the genotype Indira Kankoda (IK-1) was recorded as “resistant” showing of 16.30 and 17.43 percent fruit infestation (on fruit number and weight basis). However, the genotype RMF-7-P-1 was assigned as “susceptible” with 51.06 and 53.00 percent infestation respectively.

This paper discusses and calculates the impact of the gyroscopic effect on the increase in the agricultural machine working assemblies’ load on bearings of the chaff cutter type. This effect occurs under natural field operational conditions of this type of machine either during the change in direction of its movement or moving over irregular surface and is caused by a sudden change in the axis direction of quickly rotating masses. In a form of graph, there is a presentation of a mathematical model and exemplary results of simulation calculations for selected parameter values related to the movement and operation of machines with a high-speed drum. Calculations were conducted on the basis of analysis of technical data of working machines of the chaff cutter type. Conducted analysis of the agricultural machine working assemblies’ load on bearings showed that these loads may temporarily increase even by ten times in case of the machine turn and eight times in case of moving over irregular of surface, considerably influencing their lifetime.

Bymovirus-induced yellow mosaic diseases seriously threaten global production of autumn-sown barley and wheat, which are two of the presently most important crops around the world. Under natural field conditions, the diseases are caused by infection of soil-borne plasmodiophorid Polymyxa graminis-transmitted bymoviruses of the genus Bymovirus of the family Potyviridae. Focusing on barley and wheat, this article summarizes the achievements on taxonomy, geography and host specificity of these disease-conferring viruses, as well as the genetics of resistance in barley, wheat and wild relatives. Moreover, based on recent progress of barley and wheat genomics, germplasm resources and large-scale sequencing, the exploration and isolation of corresponding resistant genes from wheat and barley as well as relatives, no matter what a large and complicated genome is present, are becoming feasible and are discussed. Furthermore, the foreseen advances on cloning of the resistance or susceptibility-encoding genes, which will provide the possibility to explore the functional interaction between host plants and soil-borne viral pathogens, are discussed as well as the benefits for marker-assisted resistance breeding in barley and wheat.

The weathering of crude oil at sea has been researched for nearly half a century. However, there have been relatively few opportunities to validate laboratory-based predictions about the rates, relative importance, and controls of oil weathering processes (e.g., evaporation, photo-oxidation, and emulsification) under natural field conditions. The 2010 Deepwater Horizon (DWH) spill in the Gulf of Mexico provided the oil spill science community with a unique opportunity to evaluate our laboratory-based predictions in nature. With a focus on photochemical weathering, we review what we knew prior to the DWH spill, what we learned from the DWH spill, and what priority gaps in knowledge remain. Three key findings from the DWH spill are discussed. First, the rate and extent of photochemical weathering was much greater for the floating surface oil than expected based on early conceptual models of oil weathering. Second, indirect photochemical processes played a major role in the partial oxidation of the floating surface oil. Third, the extensive and rapid changes to the physical and chemical properties of oil by sunlight may influence oil fate, transport, and the selection of response tools. This review also highlights findings and predictions about photochemical weathering of oil from several decades ago that appear to have escaped the broader scientific narrative and ultimately proved true for the DWH spill. By focusing on these early predictions and synthesizing the numerous findings from the DWH spill, we expect this review will better prepare the oil spill science community to respond to the next big spill in the ocean.

We implement behavioral mechanisms in a natural field experiment to increase loan repayment rates on a peer-to-peer (P2P) lending website. The results show that text message reminders that convey lenders’ positive expectations considerably increase the likelihood that borrowers will repay their loans, whereas reminders emphasizing the adverse consequences of failure to repay loans do not have enduring effects. Our experiment results in an increase in loan repayments in the sample period. In addition, our reminders are cost-free to implement, showing the potential importance of such interventions in enhancing prosocial compliance in P2P lending. This paper was accepted by John List, behavioral economics.

Grapevine sustainability is impacted by the timing of dormancy initiation and freezing tolerance in fall and winter and chilling fulfillment and bud break in the spring. These traits have genetic and local temperature contributing factors, therefore, this study was undertaken to develop an understanding of these characteristics in four recently developed cold climate cultivars. The cold hardiness and chilling fulfillment profiles were monitored in Brianna, Frontenac gris, La Crescent and Marquette using differential thermal analyses and bud break assays. Bud cold hardiness of all cultivars increased with the declining temperatures from November through February, after which the buds began to lose freezing tolerance. There were significant differences in cold hardiness and chilling fulfillment between cultivars during the endodormant and ecodormant period of winter. Marquette had the greatest freezing tolerance from early November through midwinter suggesting it has potential as a sentinel cultivar for comparisons of new cold climate selections. Brianna was slower to acclimate and deacclimated more rapidly than the other cultivars. Chilling fulfillment under natural field or constant 4 &deg, C conditions showed no main effect differences for chilling accumulation condition, however, there were significant cultivar, condition, and time point interactions, indicating the cultivars differed in chilling fulfillment responses.

In early 2019, a US climate change and economic renewal policy proposal called the Green New Deal (GND)1 rose from obscurity to national prominence in just four months. This situation created a natural field experiment in which to study the emergence of partisan polarization. Here, we report findings from two nationally representative surveys of registered US voters that measured familiarity with and support for the GND shortly before and after the issue entered the national spotlight. Initially, there was low public awareness of the GND but majority support for it across party lines. Four months later, voters had become much more familiar with the GND and partisan polarization had increased significantly due to a sharp decrease in support among Republicans. In fact, Republicans who had heard the most about the GND were the least likely to support it. In contrast, support for the GND remained high among Democrats, and did not vary substantially across degrees of familiarity. We also identify a likely mechanism: a ‘Fox News effect’. That is, among Republicans, Fox News viewing was a significant predictor of both familiarity with the GND and opposition to it, even when controlling for alternative explanations. Opinions on climate policy in the United States are politically polarized. Here, survey research shows that opinion polarization on the Green New Deal developed rapidly due to decreasing support among Republicans, which was associated with exposure to conservative media and increasing familiarity with the policy.

Pot and field experiments were conducted to assess varietal differences in growth and yield responses of soybean (Glycine max L. Merrill) to commercial arbuscular mycorrhizal fungi (AMF) in...

Biochar is used as a soil amendment to improve soil quality and fertility. The performance of biochar changes as it ages in fields. Artificial biochar aging methods (i.e. chemical oxidation) are considered proxies for natural biochar aging and help to evaluate the long-term effects of biochar amendment in soil. However, few studies have focused on how close artificial biochar aging methods are to biochar aging in fields. A meta-analysis of 42-studies was conducted to quantitatively compare the effects of soil incubation (natural field biochar aging), chemical oxidation (chemical biochar aging) and freeze-thaw cycling (freeze-thaw biochar aging) on biochar properties, including surface and bulk element compositions (C, H, O, N), specific surface area, cation exchange capacity and pH. The results showed that the artificial biochar aging methods cannot yet simulate biochar aging in the soil. In comparison with natural field aging, chemical aging tended to have a higher degree of oxidation at the surface of the aged biochar and posed the problems of oxidation inside the biochar and the import of exogenous elements from oxidants to the biochar. Freeze-thaw aging changed only the porous structure of the biochar with no significant alterations to element compositions, in contrast with natural aging.

The persistent lack of workplace diversity in management and leadership may lead to organizational vulnerabilities. White males occupy most high-profile positions in the largest U.S. corporations whereas African Americans, Hispanics, and women are clearly underrepresented in leadership roles. While many firms and other organizations have set ambitious goals to increase demographic diversity, there is a dearth of empirical evidence on effective ways to reach them. We use a natural field experiment to test several hypotheses on effective means to attract minority candidates for top professional careers. By randomly varying the content in recruiting materials of a major financial services corporation with over 10,000 employees, we test different types of signals regarding the extent and manner in which the employer values diversity among its workers. We find that signaling explicit interest in employee diversity can reverse the ethnicity gap in rates of interest and applications, and that it has a strong positive effect on interest in openings among racial minority candidates, the likelihood that they apply, and the probability that they are selected. These results uncover an effective method for disrupting monocultures in management through a minor intervention that influences sorting among job-seekers into high-profile careers.

This paper studies the effect of providing feedback to college students on their position in the grade distribution by using a natural field experiment. This information was updated every six months during a three-year period. We find that greater grades transparency decreases educational performance, as measured by the number of examinations passed and grade point average (GPA). However, self-reported satisfaction, as measured by surveys conducted after feedback is provided but before students take their examinations, increases. We provide a theoretical framework to understand these results, focusing on the role of prior beliefs and using out-of-trial surveys to test the model. In the absence of treatment, a majority of students underestimate their position in the grade distribution, suggesting that the updated information is “good news” for many students. Moreover, the negative effect on performance is driven by those students who underestimate their position in the absence of feedback. Students who overestimate initially their position, if anything, respond positively. The performance effects are short lived—by the time students graduate, they have similar accumulated GPA and graduation rates. This paper was accepted by John List, behavioral economics.

Organic amendments improve the soil quality and plant productivity as well as help in the establishment of introduced bacteria. The present study was conducted to evaluate the interactive impact of organic amendments and plant growth promoting rhizobacteria strain Alcaligenes sp. AZ9 to improve maize productivity and soil quality. organic amendments including rock phosphate enriched compost (RPEC), biochar, and humic acid were applied in soil along with and without Alcaligenes sp. AZ9. The results revealed that the sole application of organic amendments along with Alcaligenes sp. AZ9 showed increase in growth and grain yield of maize. However, a combined application of organic amendments (RPEC, biochar, and humic acid) along with Alcaligenes sp. AZ9 showed maximum increase in plant height up to 14%, shoot dry biomass up to 30%, 1000-grains weight up to 10%, grain yield up to 31%, stover yield up to 34%, and potassium (K) concentration in grains up to 12% as compared to absolute control. The increase in nitrogen (N) and phosphorus (P) concentration in grains was non-significant over control. This treatment also improved soil biological attributes in terms of the bacterial population up to 60%, microbial biomass carbon up to 22%, soil organic carbon up to 29%, and saturation percentage of soil up to 14% as compared to control. It can be concluded that the application of organic amendments improved establishment of introduced bacteria, which could be effective in improving maize growth and yield as well as soil health.

We investigate behavioral reactions toward exogenous changes of implicit norm-relevant information in a natural field setting where customers are free to choose if and how much to pay for a service. Customers’ voluntary payments are significantly affected by subtle information cues: cues that signal a high rather than a low payment norm increase payments by some 27%. Consistent with the conjecture that this effect is in large part driven by customers’ uncertainty about the actual norm, responses are mitigated when explicit norm-relevant information is provided. Additional treatments suggest that the reactions to the cues are not driven by mere saliency but by the information deduced from the cues in the presence of uncertainty. Data are available at https://doi.org/10.1287/mnsc.2017.2937 . This paper was accepted by Uri Gneezy, behavioral economics.

This paper reports new findings on gender differences in altruism. Conducting a natural field experiment (N = 2,164) we study donation behavior in a naturally occurring environment using a matched donation design. Contrary to previous research, we find that reducing the “price of altruism” by increasing matching efficiency has a significantly stronger effect on females than on males.

In the present study, a total of 41 sediment samples were collected from the areas with different land uses: industrial (IS), urban (US), agricultural (AGS), and natural field (NS) in the northern coasts along the Persian Gulf from November 2016 to January 2017. Samples were analyzed to determine the concentration of heavy metals (Zn, Cu, Pb, Cd, Cr, and Ni). The mean concentration of Ʃ6 heavy metals in the samples taken from IS, US, AGS, NS were 2300.24, 251.02, 553.21, and 40.93 mg/kg, respectively. The predominant metals were Zn, Cu, and Pb and the mean concentrations of Ʃ3 metals (Zn, Cu, and Pb) in IS, US, AGS, NS areas were 2245.6, 241.44, 529.61, and 36.98 mg/kg, respectively. The results indicated that the mean concentrations of Ʃ6Metals/Ʃ3 metals in the IS and AGS samples were significantly higher than US and NS samples (p 0.05). Heavy metal levels (mg/kg. dry weight) in all four land uses were as follows: industrial region: Pb (1347.44) Cu (465.00) Zn (427.16) Cr (34.20) Cd (19.45) Ni (7.09); urban region: Zn (97.45) Cu (79.90) Pb (64.09) Cr (5.30) Ni (2.55) Cd (1.73); agricultural region: Zn (247.88) Pb (164.89) Cu (116.84) Cr (11.09) Ni (7.45) Cd (5.06); and natural fields: Zn (27.43) Cu (6.34) Pb (3.18) Cr (1.94) Ni (1.18) Cd (0.83). According to geo-accumulation index (I-geo), the IS, US, and AGS were classified into "highly-extremely polluted", "unpolluted-moderately polluted" and "highly polluted", respectively. Similarly, in accordance with the ecological risk index (ERI), the IS and AGS fell into the very high and considerable categories, respectively, while US land uses area was categorized as low risk. Based on the results obtained from the present study, it can be concluded that the sediments of Asalouyeh coasts in the northern part of the Persian Gulf are heavily contaminated with heavy metals, causing serious negative effects on both the human being and environment.

Presented are the results of studying the inheritance of the phenotypic reaction in reciprocal F 1 and F 2 winter triticale hybrids (x Triticosecale Wittm.) on a natural infectious background for septoria in climatic conditions of the Republic of Moldova are presented. The aim of this work was to identify sources of resistance among the genotypes of local triticale that are well adapted to septoria and study of the genetic control of the trait. The reaction of reciprocal F 1 and F 2 hybrids on susceptibility of septoria varied in the range of 0.1-3.1 points and 0-2.8 points, respectively. It has been established that the resistance of triticale to Septoria tritici can be both dominant and recessive, depending on the response of the parental genotypes and the direction of the crossing. The overdominance of S. tritici resistance was manifested in F 1 hybrids from reciprocal crossing of resistant genotypes (Podoima/Talovscaia 12 and Ingen 40). In the less favorable climatic conditions for the development of the disease (2017), F 2 hybrids obtained from crosses of the Podoima /Talovscaia 12, Ingen 40 and Ingen 93 genotypes manifested tolerance. A significant positive correlation (r = 0.52, p 2 hybrids. When creating varieties resistant to septoria and winter triticale lines, it is recommended to use adapted and less affected against the natural infectious background resistance donors Ingen 40 and Podoima /Talovscaia 12.

Growing bananas resistant to Pseudocercospora fijiensis, the cause of black Sigatoka, is the preferred disease control strategy for resource-poor farmers. Banana breeding programs in east Africa have developed 27 Matooke hybrids (commonly known as NARITAs) with higher yields than local landraces. To assess the response of NARITA hybrids to P. fijiensis, 22 hybrids were evaluated under natural field conditions in four locations—Kawanda and Mbarara in Uganda, and Maruku, and Mitarula in Tanzania—between 2016 and 2018 for three crop cycles. Black Sigatoka was visually assessed and the area under the disease progress curve calculated for each plant over time. Significant differences (p &lt, 0.001) were observed between genotypes, environments, and their interaction. The highest contributor to black Sigatoka severity (39.1%) was the environment, followed by the genotype (37.5%) and the genotype Χ environment interaction (GEI) (23.4%). NARITA 2, 7, 14, 21 and 23 were resistant and the most stable hybrids across locations. If other attributes such as the yield and taste are acceptable to end-users, these hybrids can be released to farmers in the region to replace highly susceptible landraces. Mitarula was identified as an ideal site for evaluating banana against black Sigatoka and should be used as a representative location to minimize costs of disease evaluations.

The architectural design of animal structures forms part of an individual's extended phenotype that can be subjected to strong selection pressures. We examined cocoon architectural dimorphism in robin moths (Hyalophora cecropia), which construct multilayered silk-woven cocoons that possess either a ‘baggy’ or ‘compact’ morphology. These dimorphic cocoons reflect extended phenotypes that can enable survival during a critical developmental period (pupal stage to adult emergence), with cocoons occurring either sympatrically or as monomorphic groups across different climatic regions in North America. We hypothesized that cocoon dimorphism is related to the cocoon's role as a mediating barrier for moisture. We predicted that the macro- and micro-architectural differences between the cocoon morphs would be consistent with this function. We compared the cocoon morphs in terms of their orientation when spun under natural field conditions, examined how these orientations affected cocoon water absorption under simulated rain trials, and performed material surface tests to compare the hydrophobicity of cocoons. We found that compact cocoons had traits that increased water resistance, as they had significantly greater hydrophobicity than baggy cocoons, because they absorbed less water and released water vapor faster. In contrast, the increased water absorptiveness of baggy cocoons can allow for greater moisture retention, a function related to the prevention of desiccation. Our study suggests that cocoon dimorphism in robin moths reflects distinct architectural syndromes, in which cocoons are spun to optimize either water resistance or retention. These different functions are consistent with strategies that act to respond to uncertain external environmental conditions that an individual might encounter during development.