Contest Duration Research Articles

Contest design and solvers' engagement behaviour in crowdsourcing: The neo-configurational perspective

Companies face the challenges of attracting solvers and motivating them to dedicate their time and effort to develop solutions in crowdsourcing contests. Previous research emphasizes the importance of crowdsourcing contest design for fostering solvers' engagement. However, even though contests are designed as a combination of various design elements, such as seeker's identity disclosure, seeker's status, contest duration and monetary prize, prior studies primarily focused on independent effects of these elements, ignoring their interdependency. Building our study on the social exchange theory, we adopt the neo-configurational perspective to explore effective designs of crowdsourcing contests and contribute to our understanding of how contest design elements interact to jointly stimulate solvers' engagement. By the means of the fuzzy-set Qualitative Comparative Analysis of 277 contests, we show that the combination of long contest duration and high monetary prize plays a significant role in attracting solvers to join crowdsourcing contests, while these elements need to be additionally reinforced by the seeker's identity disclosure and its high status to motivate solvers to actually commit to problem solving. In this way, our study provides unique insights about the differences between contest designs that only initially attract solvers and designs that actually motivate them to create value for seeker companies. It fills the gap where previous research failed to embrace the configurational character of contest design, while offering unique guidance to managers who struggle to attract solvers to join and contribute to crowdsourcing initiatives.

Experimental quantification of genetic and ontogenetic effects on fighting behavior in the broad-horned flour beetle

Most animal behaviors show large within- and among-individual variation, and this includes competitive male behaviors. With male fighting for example, aggressiveness often correlates with dominance, and contest duration varies with age. However, few studies have directly quantified how mean aggressiveness and contest duration, the variation among individuals in both traits, and the relationship among them, vary with age. Here we address these gaps and examine the effect of male age and genotype on two key aspects of male fighting behavior - aggressiveness (here measured as latency to fight) and contest duration - and the relationship between them. We do this using isogenic lines of the broad-horned flour beetle Gnatocerus cornutus. We observed fighting behavior of paired males of similar body size and age. Using uni- and multivariate mixed models, we show that although there was a significant difference between younger and older males in contest duration, mean aggressiveness was not affected by male age. However, the variation in aggression and fight duration varied with age, being greater in younger and older males respectively. Additionally, although there was a positive correlation between aggressiveness and contest duration in younger males, this relationship was not found in older males. Finally, the only significant genetic effect was for aggression in younger males. Our study shows that age differentially shapes key components of male fighting behavior as well as the relationship among them, highlighting the dynamic nature and context-dependence of fighting.

Relative size and chemical information impact mixed-sex contests in the crayfish Faxonius rusticus Girard, 1852 (Decapoda: Astacidea: Cambaridae)

Abstract Male and female differences in contest strategies present a valuable exploration of varied access to relevant ecological information. Crayfish studies have revealed that males and females likely use different sources of information to dictate contest persistence and the difference becomes most apparent in mixed-sex contests. We examined the role of chemical information in mixed-sex contest dynamics and assessment by randomly pairing mixed-sex pairs that were either size-matched or size asymmetric. The lesion treatments consisted of eliminating olfactory cells on the antennules, the main organ for chemical detection in crayfishes. Dyads were classified as control (both intact), female-lesioned (females lesioned, males intact), or male-lesioned (females intact, males lesioned). Statistical analysis revealed that sex-based size difference, lesion treatment, and winner’s sex dictated contest duration. Regressions did not reveal evidence of one particular assessment strategy for control dyads, but male- and female-lesioned contests demonstrated weak relationships indicative of a possible self-assessment strategy. Behavioral network analyses indicated that chemical information is important for transitions between behavioral states and that the sexes use this information differentially. We suggest chemical information is important for both males and females in contest assessment, but the information contained in the signal or how the participants use the information for assessment likely differs across the sexes.

Third-party intervention and post-conflict behaviour in agonistic encounters of pigs (Sus scrofa)

BackgroundThird-party interference in agonistic contests entails a deliberate intervention in an ongoing fight by a bystanding individual (third party) and may be followed by post-conflict social behaviour to provide support to a specific individual. The mechanisms behind third-party intervention are, however, still largely understudied. The aim of this study was to investigate third-party interference, with the predictions that (1) the interferer derives benefits from its action by winning a fight, (2) that patterns of intervention depend on familiarity, (3) that dyadic fights last longer than triadic fights, and (4) that interferers engage in non-agonistic social behaviours afterwards. Pre-pubertal pigs (Sus scrofa) (n = 384) were grouped with one familiar and four unfamiliar conspecifics (all non-kin) to elicit contests for dominance rank. Third-party interference was analysed for the first 30 min after grouping, along with the behaviour (nosing or aggression), contest duration, contest outcome, and interferer behaviour after the fight (post-conflict social behaviour).ResultsThree types of interference were observed: non-agonistic involvement (nose contact) by the interferer in a dyadic fight; a triadic fight with each of three contestants fighting one opponent at a time; and triadic fights with two opponents jointly attacking the third one (two-against-one fights). The likelihood of a third-party intervention to occur did not depend on the presence of a familiar animal in the fight. However, once intervention was triggered, interferers attacked unfamiliar fight initiators more than familiar ones. Two-against-one fights lasted longer than other triadic fights and occurred more often when both initial contestants were females. Results of 110 triadic fights (out of 585 fights in total) revealed that interferers were more likely to win compared to the initial opponents at equal body weight. The most common post-conflict behaviour displayed by the interferer was agonistic behaviour towards another group member, independently of familiarity.ConclusionsThe general lack of discrimination for familiarity suggests interference is not driven by support to familiar individuals in pigs. The results show that intervening in an ongoing fight gives the interferer a high chance of contest success and may be a strategy that is beneficial to the interferer to increase its dominance status.

Sex-specific difference in agonistic sounds depends on size of sonic organs in fishes: Testing the hypothesis in the croaking gourami (Labyrinth fishes).

In most vocal fish species, females possess smaller sound-generating organs and vocalize less than males. In certain cases females lack sonic organs, in others differences between sexes are unknown. This study analyzes in detail the relationship between sexual dimorphism of sonic organs and the characteristics of agonistic behavior and of sounds recorded under the same behavioral conditions in a vocal fish species, the croaking gourami Trichopsis vittata. During agonistic contests both sexes stretch and pluck two enhanced (sonic) tendons when beating pectoral fins alternately, resulting in a series of double-pulsed bursts, termed croaking sound. The following anatomical, behavioral, and acoustic variables were analyzed: diameter of enhanced tendons in each specimen, duration of same-sex dyadic contests, number and duration of lateral display bouts and of sounds, number of single- and double-pulsed bursts, burst period, peak-to-peak amplitudes of pulses, dominant frequency and sound pressure level (SPLrms). Female sonic tendons were approximately one-fifth smaller than male's of the same size. Six out of seven behavioral variables did not differ between sexes. Sound characteristics were similar in both sexes except for SPLs, which were on average 5 dB lower in females. The degree of sexual dimorphisms in sonic organs may explain differences in sound characteristics. Sounds differ only in one sound characteristic (SPLrms) in T.vittata, in contrast with the congeneric Trichopsispumila which possesses a more pronounced sexual dimorphism in sonic organs and in which agonistic sounds differ in all sound properties between sexes.

Modelling animal contests based on spatio-temporal dynamics.

We present a general theoretical model for the spatio-temporal dynamics of animal contests. Inspired by interactions between physical particles, the model is formulated in terms of effective interaction potentials, which map typical elements of contest behaviour into empirically verifiable rules of contestant motion. This allows us to simulate the observable dynamics of contests in various realistic scenarios, notably in dyadic contests over a localized resource. Assessment strategies previously formulated in game-theoretic models, as well as the effects of fighting costs, can be described as variations in our model's parameters. Furthermore, the trends of contest duration associated with these assessment strategies can be derived and understood within the model. Detailed description of the contestants' motion enables the exploration of spatio-temporal properties of asymmetric contests, such as the emergence of chase dynamics. Overall, our framework aims to bridge the growing gap between empirical capabilities and theory in this widespread aspect of animal behaviour.

Stag beetle Cyclommatus mniszechi employs both mutual- and self-assessment strategies in male-male combat

Animals may base contest decisions on their fighting ability alone (self-assessment) or also their opponents’ (mutual assessment). Many male stag beetles develop disproportionately enlarged mandibles and use them as weapons. Information on their assessment strategy is limited. To investigate their assessment strategy and whether they adopt the same strategy at different stages of contests, we used food to encourage male Cyclommatus mniszechi of different (random pairings) or similar (ML-matched pairings) mandible length (ML) to interact. For the random pairings, losers had shorter mandibles than winners and were faster to feed. Overall contest duration and the tendency to escalate to tussles associated positively with winners’ ML and average ML in the random and the ML-matched pairings, respectively, consistent with self-assessment. Non-tussle phase duration associated positively with average ML in the ML-matched pairings, consistent with self-assessment. Tussle phase duration, however, positively associated with losers’ ML in the random pairings and had no association with average ML in the ML-matched pairings, consistent with mutual assessment. These results show that (1) the males employ both assessment strategies, (2) winners have more control over contest intensity than losers, and (3) males with shorter mandibles are quicker to feed and also more likely to lose fights.

Comparing the dynamics of agonistic interactions between the native crayfish Faxonius erichsonianus Faxon, 1898 and the invasive F. virilis Hagen, 1870 (Decapoda: Astacidea: Cambaridae)

Abstract Alabama is a hotspot for aquatic biodiversity in North America, but that biodiversity is currently jeopardized by anthropogenic influence and invasive species. Alabama holds nearly a quarter of North America’s crayfish species, but recent introduction of invasive crayfishes poses a threat to crayfish biodiversity in the region. Previous studies suggest higher basal aggression in invasive species allows them to outcompete native species by more efficiently seizing and holding resources. Faxonius virilis (Hagen, 1870) is an invasive crayfish currently spreading throughout Alabama. Our aim was to determine if differences in basal aggression exist between an Alabama native, Faxonius erichsonianus (Faxon, 1898), and the invasive F. virilis. Individuals were used in size-matched dyadic fight trials housed in a specialized arena. Three treatment groups were used to compare basal aggression differences: native versus native, invasive versus invasive, and interspecific. Videos of fight trials were reviewed, and duration and intensity of fights were recorded using a previously established ethogram. Contest duration between individuals was compared using Kruskal-Wallis tests with a Wilcoxon post-hoc. Analyses showed the invasive control treatment was significantly (P = 0.041) shorter than both the native control and interspecific treatments; however, interspecific trials had higher intensity contests than either control treatment. These results did not show that the invasive F. virilis are more aggressive than F. erichsonianus, suggesting that a closer look is necessary to determine the factors affecting the invasion success of F. virilis. The F. virilis invasion may be attributed to other factors like fecundity or growth.

Sexual dimorphism in ritualized agonistic behaviour, fighting ability and contest costs of Sus scrofa

BackgroundSexual selection has driven sexual dimorphism in agonistic behaviour in many species. Agonistic behaviour is fundamentally altered by domestication and captivity, but it is unclear whether ancestral sex differences remain. We aimed to evaluate the effect of sex on agonistic behaviour, fighting ability and contest costs. We studied this in domestic pigs (Sus scrofa) where aggression compromises welfare, and sexual dimorphism in aggression has been inconclusively demonstrated. Behaviour and physiology of 827 male and female juvenile pigs were studied during resident-intruder tests and dyadic contests at various ages, while accounting for the relative body weight difference between the opponents.ResultsMales won in 79% of contests against females, even when at a large weight disadvantage. The effect of sex increased with age, with males having a 138 times higher likelihood of winning than females when 13 weeks old. In dyadic contests, males invested more time in non-damaging agonistic display behaviour and took longer before escalating into damaging aggression. Males showed ritualized display that included foaming from the mouth and piloerection of the neck hair, which was nearly always absent in females. Contest costs in terms of contest duration, blood lactate and skin lesions where higher for males, especially when fighting another male.ConclusionsProfound sex differences were present for agonistic behaviour, fighting ability and contest costs, and became more pronounced as animals got older. Males invested more in ritualized display before escalating into costly fights, whereas females attacked sooner but also terminated contests more rapidly and with fewer costs. The sexual dimorphism in agonistic behaviour in juvenile domestic pigs is in line with the evolutionary relevance for females’ maternal defence and males’ competition for females.

Costly Waiting in Dynamic Contests: Theory and Experiment

We extend the war of attrition by studying a three-period dynamic contest game. In our game, players can fight against their opponents at certain period of the contest and can flee at any time. Waiting is costly. We focus on the role of waiting costs and show that the value of waiting costs is a key factor in determining the type of equilibrium in such dynamic contests. Specifically, as waiting costs increase, contests end earlier, battles are less likely to occur, and the weaker player in a pair is more likely to flee. A lab experiment verifies most key features of our model. However, unlike theoretical predictions, we find that as waiting costs increase, the duration of contests and the frequency of battles fail to drop as significantly as theory predicted. Moreover, we find that in each treatment, individual players exit the contest significantly earlier than predicted.

Individuality and function of chemical signals during conflict resolution of a mammal.

Individual recognition via communication signals is a critical component of social behavior, and provides the basis of conflictresolution, territorial behavior, and mate choice. However, the function of chemical signals in mammalian individual recognition and conflict resolution has largely been unexplored despite olfaction being a dominant sensory modality in many mammalian species. Here, we describe behavioral tests designed to evaluate the potential role of forehead gland secretions during conflict related to territorial defense in male Great Himalayan leaf-nosed bats. We used gas chromatography-mass spectrometry to quantify the chemical composition. Our results showed that forehead gland secretions contain 16 categories of compounds, including 84 volatile compounds. The concentrations of compounds and their categories differed significantly among individuals. Moreover, behavioral studies indicated that males can use chemical signals for individual recognition. Contests were staged between males with or without functioning forehead glands. Paired males without functioning forehead glands displayed more physical contact and longer contest duration compared with pairs with functioning glands. Moreover, males with a functioning gland were more likely to win in contests when paired with males without a functioning gland. These findings support a growing amount of evidence that chemical signals play a vital role in conflict resolution in mammals.

Attracting High‐Quality Contestants to Contest in the Context of Crowdsourcing Contest Platform

Contests have long existed to source ideas and solutions. The emergence of crowdsourcing contest platforms greatly reduces the costs and broadens the reach of running contests by facilitating access to a large pool of labor, making contests a cost‐efficient approach to procure ideas/solutions even for employers of limited resources. As a result, the use of contests surges and there is a flux of small‐to‐medium size contests to these platforms. This study focuses on these new waves of small‐to‐medium‐size contests on crowdsourcing contest platforms and extends the literature in several ways: First, prior literature focuses extensively on contest prize, we also consider the effect of contest duration, which plays salient role on contest platforms. Our findings provide evidence that contest duration affects both the number and the quality of contestants attracted to a contest. Second, prior literature assumes contests exist independently and that the quality distribution of contestants is exogenous; accordingly, the number of contestants can be regarded as a proxy of contest performance. We show that contest design parameters have direct effects on the quality distribution of contestants. Specifically, increasing contest duration, while attracting more contestants, results in a downward shift on the quality distribution of the contestants attracted to the contest. Third, recognizing that each contest does not exist independently on crowdsourcing contest platforms, we also incorporate the number of competing contests in our model. Our results provide practical recommendations on how to set up successful contests and attract high‐quality contestants to a contest on a crowdsourcing contest platform.

Contests between male New Zealand sheet-web spiders, Cambridgea plagiata (Araneae: Desidae)

ABSTRACT Male competition for females can often take the form of direct physical contests. The outcome of a given contest or the decision to persist is determined by the resource holding potential (RHP) of rivals, which often corresponds to body size or weapon size. Males of the endemic New Zealand sheet-web spider Cambridgea plagiata Forster & Wilton 1973 have exaggerated chelicerae that are used in contests to gain access to females. We staged male–male contests in the field to determine the factors contributing to contest duration and outcome. The current models which describe how individuals make decisions to persist in a contest fall broadly into (i) energetic war of attrition or pure self-assessment, (ii) mutual assessment, and (iii) cumulative assessment. Our results showed that male body size was the key predictor in determining the winner of a given contest. The durations of contests were more consistent with predictions from either mutual or cumulative assessment models. We highlight that staging contests in the field may result in more realistic results and natural behaviours. Similar to the congener C. foliata, it appears that further development of current contest models may be required to understand male contests in sheet-web spiders.

Web wars: males of the golden orb-web spider invest more in fights for mated females

AbstractIn addition to resource value, the cost of finding mates may affect how much males invest in fights for females. The cost of finding females may be imposed through natural factors extrinsic to males, such as female spatial distribution and predation pressure, which can be challenging to simulate in laboratory conditions. Therefore, studies under natural conditions may be suitable for understanding how the costs of finding mating partners affect male investment in fights. We used the spider Trichonephila clavipes to evaluate the hypotheses that males in field conditions invest more in contests for access to 1) unmated and 2) more fecund females and 3) when access to females is harder. To test these hypotheses, we recorded the occurrence, duration, and escalation of induced contests between males located in webs of females that differed in reproductive status (estimated by female life stage), fecundity (estimated by female abdominal area), and spatial distribution (i.e., isolated or aggregated with webs of other females). The occurrence and duration of contests were unrelated to female value or search costs. However, the probability for escalation was higher when males were fighting for adult (and probably mated) females. We also found that males tended to start a contest more often in aggregated webs. These results indicate that males of T. clavipes adjust investment in contests but contrarily to what we expected. We suggest that males invest more in contests for adult females because they are defending females that they previously fertilized to avoid sperm competition.

Optimal Duration of Innovation Contests

Problem definition : We study the contest duration and the award scheme of an innovation contest where an organizer elicits solutions to an innovation-related problem from a group of agents. Academic/practical relevance : Our interviews with practitioners at crowdsourcing platforms have revealed that the duration of a contest is an important operational decision. Yet, the theoretical literature has long overlooked this decision. Also, the literature fails to adequately explain why giving multiple unequal awards is so common in crowdsourcing platforms. We aim to fill these gaps between the theory and practice. We generate insights that seem consistent with both practice and empirical evidence. Methodology : We use a game-theoretic model where the organizer decides on the contest duration and the award scheme while each agent decides on her participation and determines her effort over the contest duration by considering potential changes in her productivity over time. The quality of an agent’s solution improves with her effort, but it is also subject to an output uncertainty. Results : We show that the optimal contest duration increases as the relative impact of the agent uncertainty on her output increases, and it decreases if the agent productivity increases over time. We characterize an optimal award scheme and show that giving multiple (almost always) unequal awards is optimal when the organizer’s urgency in obtaining solutions is below a certain threshold. We also show that this threshold is larger when the agent productivity increases over time. Finally, consistent with empirical findings, we show that there is a positive correlation between the optimal contest duration and the optimal total award. Managerial implications : Our results suggest that the optimal contest duration increases with the novelty or sophistication of solutions that the organizer seeks, and it decreases when the organizer can offer support tools that can increase the agent productivity over time. These insights and their drivers seem consistent with practice. Our findings also suggest that giving multiple unequal awards is advisable for an organizer who has low urgency in obtaining solutions. Finally, giving multiple awards goes hand in hand with offering support tools that increase the agent productivity over time. These results help explain why many contests on crowdsourcing platforms give multiple unequal awards.

Round-Number Bidding as an M&A Strategy

Round number initial offers are pervasive in many bargaining situations. We examine the prevalence and outcome of such offers in the market for merger and acquisition targets. We find that the practice of making initial offers at round transaction values is associated with shorter contest duration and lower probability of encountering challenging bids. Our results suggest that round numbers are chosen strategically as a signal by impatient bidders who are willing to take a slight drive-up of price to secure a timely purchase and prevent competing bidders from entering the game.

Contest behaviour varies in relation to reproductive opportunities and reproductive success in the fallow deer

Theory expects contestants to adjust their investment in fighting in line with the perceived value of a resource. Thus, we expect to see an increase in contest duration or aggressive actions if the subjective value of the resource is estimated to be high relative to occasions where the value is estimated to be low. Although this expectation is well established in theory, we know little about how contestants structure their contests over resources in the wild: in particular, how variation in resource availability affects how contestants invest in fights. The objectives of this study were twofold: to examine whether (1) the structure of male–male fights varied with presence and abundance of oestrous females in the population and (2) there was an association between investment in fighting and mating success, during fights between fallow deer, Dama dama. Subordinate but not dominant contestants increased their rate of attacking actions when there were oestrous females in the population. However, there was no association between dominant or subordinate contest actions and variation in the number of oestrous females on any single day. Regarding mating success, dominant males that increased their attack rate during fights were more likely to achieve a mating than those that did not, although this investment in attacks was not associated with the number of matings obtained. Conversely, mating success was associated with a reduction in the number of parallel walks for subordinate contestants. Therefore, subordinate males achieved more matings when ritualized display behaviour was reduced or omitted from the contest. These results suggest that a desperado effect may be present, and that contestants use an estimate of resource value rather than opponent quality when investing in contests.

A Theoretical and Empirical Investigation of Feedback in Ideation Contests

Ideation contests are commonly used across public and private sectors to generate new ideas for solving problems, creating designs, and improving products or processes. In such a contest, a firm or an organization (the seeker) outsources an ideation task online to a distributed population of independent agents (solvers) in the form of an open call. Solvers compete to exert efforts and the one with the best solution wins a bounty. In evaluating solutions, the seeker typically has subjective taste that is unobservable to solvers. In practice, the seeker often provides solvers with feedback, which discloses useful information about her private taste. In this study, we develop a game‐theoretic model of feedback in unblind ideation contests, where solvers’ solutions and the seeker's feedback are publicly visible by all. We show that feedback plays an informative role in mitigating the information asymmetry between the seeker and solvers, thereby inducing solvers to exert more efforts in the contest. We also show that some key contest and solver characteristics (CSC, including contest reward, contest duration, solver expertise, and solver population) have a direct effect on solver effort. Interestingly, by endogenizing the seeker's feedback decision, we find that the optimal feedback volume increases with contest reward, contest duration, solver expertise, but decreases with solver population. Thus, CSC elements also have an indirect effect on solvers’ effort level, with feedback volume mediating this effect. Employing a dataset from Zhubajie.com , a leading online ideation platform in China, we find empirical evidence that is consistent with these theoretical predictions.

Both sexes produce sounds in vocal fish species: testing the hypothesis in the pygmy gourami (labyrinth fishes).

In vocal fish species, males possess larger sound-generating organs and signal acoustically with pronounced sex-specific differences. Sound production is known in two out of three species of croaking gouramis (Trichopsis vittata and T. schalleri). The present study investigates sex-specific differences in sonic organs, vocalizing behaviour and sounds emitted in the third species, the pygmy gourami, T. pumila, in order to test the hypothesis that females are able to vocalize despite their less-developed sonic organs, and despite contradictory reports. Croaking gouramis stretch and pluck two enhanced (sonic) pectoral fin tendons during alternate fin beating, resulting in a series of double-pulsed bursts, termed croaking sound. We measured the diameter of the first and second sonic tendon and showed that male tendons were twice as large as in similar-sized females. We also determined the duration of dyadic contests, visual displays, number of sounds and buttings. Sexes differ in all sound characteristics but in no behavioural variable. Male sounds consisted of twice as many bursts, a higher percentage of double-pulsed bursts and a higher burst period. Additionally, male sounds had a lower dominant frequency and a higher sound level. In summary, female pygmy gouramis possessed sonic organs and vocalized in most dyadic contests. The sexual dimorphism in sonic tendons is clearly reflected in sex-specific differences in sound characteristics, but not in agonistic behaviour, supporting the hypothesis that females are vocal.

Crowdsourcing in Software Development: Empirical Support for Configuring Contests

Despite the extensive adoption of crowdsourcing for the timely, cost-effective, and high-quality completion of software development tasks, a large number of crowdsourced challenges are not able to acquire a winning solution, on time, and within the desired cost and quality thresholds. A possible reason for this is that we currently lack a systematic approach that would aid software managers during the process of designing software development tasks that will be crowdsourced. This paper attempts to extend the current knowledge on designing crowdsourced software development tasks, by empirically answering the following management questions: (a) what type of projects should be crowdsourced; (b) why should one crowdsource-in terms of acquired benefits; (c) where should one crowdsource-in terms of application domain; (d) when to crowdsource-referring to the time period of the year; (e) who will win or participate in the contest; and (f) how to crowdsource (define contest duration, prize, type of contest etc.) to acquire the maximum benefits-depending on the goal of crowdsourcing. To answer the aforementioned questions, we have performed a case study on 2,209 software development tasks crowdsourced through TopCoder platform. The results suggest that there are significant differences in the level to which crowdsourcing goals are reached, across different software development activities. Based on this observation we suggest that software managers should prioritize the goals of crowdsourcing, decide carefully upon the activity to be crowdsourced and then define the settings of the task.