Task Effort Research Articles

Active Intent Disambiguation for Shared Control Robots.

Assistive shared-control robots have the potential to transform the lives of millions of people afflicted with severe motor impairments. The usefulness of shared-control robots typically relies on the underlying autonomy's ability to infer the user's needs and intentions, and the ability to do so unambiguously is often a limiting factor for providing appropriate assistance confidently and accurately. The contributions of this paper are four-fold. First, we introduce the idea of intent disambiguation via control mode selection, and present a mathematical formalism for the same. Second, we develop a control mode selection algorithm which selects the control mode in which the user-initiated motion helps the autonomy to maximally disambiguate user intent. Third, we present a pilot study with eight subjects to evaluate the efficacy of the disambiguation algorithm. Our results suggest that the disambiguation system (a) helps to significantly reduce task effort, as measured by number of button presses, and (b) is of greater utility for more limited control interfaces and more complex tasks. We also observe that (c) subjects demonstrated a wide range of disambiguation request behaviors, with the common thread of concentrating requests early in the execution. As our last contribution, we introduce a novel field-theoretic approach to intent inference inspired by dynamic field theory that works in tandem with the disambiguation scheme.

The role of dopamine in dynamic effort-reward integration

When deciding to act, the neurotransmitter dopamine is implicated in a valuation of prospective effort and reward. However, its role in dynamic effort-reward integration during action, a process central to everyday behaviour, remains unclear. In a placebo-controlled, within-subject, study, we probed the impact of increasing brain dopamine levels (150 mg of levodopa) and blocking dopamine receptors (1.5 mg of haloperidol) in the context of a novel dynamic effort task in healthy human subjects. We show that modulating homoeostatic dopamine balance distinctly alters implicit and explicit effort allocation as a function of instantaneous reward. Pharmacologically boosting dopamine enhanced motor vigour, reflected in an implicit increase in effort allocation for high rewards. Conversely, pharmacological blockade of dopamine attenuated sensitivity to differences in reward context, reflected in reduced strategic effort discounting. These findings implicate dopamine in an integration of momentary physical experience and instantaneous reward, suggesting a key role of dopamine in acting to maximise reward on the fly.

Measuring Mastery Behaviors at Scale: The Persistence, Effort, Resilience and Challenge-Seeking Task (PERC)

Mastery behaviours — seeking out challenging tasks and continuing to work on them despite difficulties — are integral to achievement but difficult to measure with precision. The current study reports on the development and validation of the computer-based persistence, effort, resilience, and challenge-seeking (PERC) task in two demographically diverse samples of adolescents (total N = 3,188). We present evidence for convergent validity with self-reported mastery behaviours and learning mindsets, discriminant validity from theoretically unrelated constructs, and incremental predictive validity for grade point average (GPA). Results suggest that the PERC task may be a useful tool for assessing mastery behaviours at scale.

Modeling Dynamic Allocation of Effort in a Sequential Task Using Discounting Models.

Most rewards in our lives require effort to obtain them. It is known that effort is seen by humans as carrying an intrinsic disutility which devalues the obtainable reward. Established models for effort discounting account for this by using participant-specific discounting parameters inferred from experiments. These parameters offer only a static glance into the bigger picture of effort exertion. The mechanism underlying the dynamic changes in a participant's willingness to exert effort is still unclear and an active topic of research. Here, we modeled dynamic effort exertion as a consequence of effort- and probability-discounting mechanisms during goal reaching, sequential behavior. To do this, we developed a novel sequential decision-making task in which participants made binary choices to reach a minimum number of points. Importantly, the time points and circumstances of effort allocation were decided by participants according to their own preferences and not imposed directly by the task. Using the computational model to analyze participants' choices, we show that the dynamics of effort exertion arise from a combination of changing task needs and forward planning. In other words, the interplay between a participant's inferred discounting parameters is sufficient to explain the dynamic allocation of effort during goal reaching. Using formal model comparison, we also inferred the forward-planning strategy used by participants. The model allowed us to characterize a participant's effort exertion in terms of only a few parameters. Moreover, the model can be adapted to a number of tasks used in establishing the neural underpinnings of forward-planning behavior and meta-control, allowing for the characterization of behavior in terms of model parameters.

German Adaptation of the Subjective Vitality Scales (SVS-G)

AbstractSubjective vitality is a positive feeling of aliveness and energy, and it is a crucial aspect of well-being. The Subjective Vitality Scales (SVS) have been developed to measure subjective vitality both at the individual difference level and the state level in English-speaking samples. We translated the SVS into German (the SVS-G) and examined their psychometric properties. In Study 1 (N=260), we found that two correlated factors (Factor 1: individual difference level; Factor 2: state level) with five items each constituted a useful structure for the SVS-G. Moreover, the scores on the individual difference scale were more stable than the scores on the state scale. We also found partial evidence for the measurement invariance over a period of three weeks. Conforming to our expectations, Study 2 (N=296) revealed that the SVS-G scores were related to positive and negative affect but could still be distinguished from the affect variables. In line with previous findings, Study 3 (N=203) showed that SVS-G scores are related to well-being variables (happiness and joviality) and the perceived capacity to actively perform effortful tasks (attentiveness and capacity for self-control). Across all the studies, the SVS-G showed satisfying inner consistency, and the two consideration levels (individual differences vs. state) could be differentiated. The initial evidence suggests that overall, the SVS-G have good psychometric properties.

The Importance of Various Indicators of Active Learning on the Enhancement of Saudi Students’ Motivation and English Achievement: An Experimental Study

This experimental study sought to examine the impact of four indicators of active learning (i.e., elaborated feedback, group work, situated learning, and videos and pictures in classroom instruction) on the enhancement of Saudi students’ various motivational constructs (i.e., self-efficacy, task value, and effort expenditure) and English achievement. Participants were 289 university students, and the data were collected at three time points: Time 1 (before the intervention), Time 2 (in the middle of the intervention), and Time 3 (after the intervention). The findings of repeated measures ANOVA and follow-up t-tests revealed that the intervention had small impacts on all the variables at Time 2 (in the middle of the intervention). However, at Time 3 (after the intervention), the intervention had small impacts on effort expenditure and task value, a moderate impact on academic achievement, and a large impact on self-efficacy. In general, the evidence obtained provides important implications for educational practices and further research development.

How does symbolic success affect redistribution in left-wing voters? A focus on the 2017 French presidential election.

Redistribution preferences depend on factors such as self-interest and political views. Recently, Deffains et al. (2016) reported that redistributive behavior is also sensitive to the actual experience of success or failure in a real effort task. While successful participants ('overachievers') are more likely to attribute their success to their effort rather than luck and opt for less redistribution, unsuccessful participants ('underachievers') tend to attribute their failure to external factors and opt for more redistribution. The aim of the present study was to test how the experience of success (symbolic success) and political views interact in producing redistributive behavior in an experimental setting. The study was conducted during the 2017 French presidential election. Our sample was biased towards left-wing, and most participants reported voting for Mélenchon, Hamon or Macron. Our findings reveal that 1) Macron voters redistribute less than Hamon voters who themselves redistribute less than Mélenchon voters, 2) overachievers redistribute less than underachievers only among Mélenchon voters. This suggests that redistributive behavior is governed primarily by political opinions, and that influence by exogenous manipulation of symbolic success is not homogenous across left-wing political groups.

Judgments of effort exerted by others are influenced by received rewards

Estimating invested effort is a core dimension for evaluating own and others’ actions, and views on the relationship between effort and rewards are deeply ingrained in various societal attitudes. Internal representations of effort, however, are inherently noisy, e.g. due to the variability of sensorimotor and visceral responses to physical exertion. The uncertainty in effort judgments is further aggravated when there is no direct access to the internal representations of exertion – such as when estimating the effort of another person. Bayesian cue integration suggests that this uncertainty can be resolved by incorporating additional cues that are predictive of effort, e.g. received rewards. We hypothesized that judgments about the effort spent on a task will be influenced by the magnitude of received rewards. Additionally, we surmised that such influence might further depend on individual beliefs regarding the relationship between hard work and prosperity, as exemplified by a conservative work ethic. To test these predictions, participants performed an effortful task interleaved with a partner and were informed about the obtained reward before rating either their own or the partner’s effort. We show that higher rewards led to higher estimations of exerted effort in self-judgments, and this effect was even more pronounced for other-judgments. In both types of judgment, computational modelling revealed that reward information and sensorimotor markers of exertion were combined in a Bayes-optimal manner in order to reduce uncertainty. Remarkably, the extent to which rewards influenced effort judgments was associated with conservative world-views, indicating links between this phenomenon and general beliefs about the relationship between effort and earnings in society.

Toward a Theory of Systems Engineering Processes: A Principal–Agent Model of a One-Shot, Shallow Process

Systems engineering processes (SEPs) coordinate the effort of different individuals to generate a product satisfying certain requirements. As the involved engineers are self-interested agents, the goals at different levels of the systems engineering hierarchy may deviate from the system-level goals, which may cause budget and schedule overruns. Therefore, there is a need of a systems engineering theory that accounts for the human behavior in systems design. As experience in the physical sciences shows, a lot of knowledge can be generated by studying simple hypothetical scenarios, which nevertheless retain some aspects of the original problem. To this end, the objective of this article is to study the simplest conceivable SEP, a principalagent model of a one-shot, shallow SEP. We assume that the systems engineer (SE) maximizes the expected utility of the system, while the subsystem engineers (sSE) seek to maximize their expected utilities. Furthermore, the SE is unable to monitor the effort of the sSE and may not have complete information about their types. However, the SE can incentivize the sSE by proposing specific contracts. To obtain an optimal incentive, we pose and solve numerically a bilevel optimization problem. Through extensive simulations, we study the optimal incentives arising from different system-level value functions under various combinations of effort costs, problem-solving skills, and task complexities. Our numerical examples show that, the passed-down requirements to the agents increase as the task complexity and uncertainty grow and they decrease with increasing the agents' costs.

Oxytocin modulates responsibility attribution and hypothetical Resource allocation during cooperation

Reasonable responsibility attribution and resource allocation in intragroup contexts benefit the evolution of group cooperation. Oxytocin (OT) has been shown to promote prosocial behavior; however, it remains unclear whether OT affects responsibility attribution and hypothetical resource allocation. In the present study, participants were intranasally administered OT or placebo (PLC) before a response task with a partner. The participant could win a certain amount of money depending on the group’s performance, which was determined by the faster player. The contribution was manipulated to be similar in the first phase, while the participants could individually contribute more in the second phase. Our results show that both groups attributed more credit to the player who performed better in a trial. Moreover, reward magnitude only enhanced effort-based attribution in the OT group. Although both groups proposed to distribute money based on individual efforts, the PLC group increased their effort-based allocation when they contributed more, regardless of the fact that the money was eventually equally distributed. Our study demonstrates that OT modulates responsibility attribution and hypothetical resource allocation in different manners, suggesting that OT has different effects on a participant’s perception of individual contribution and fairness when allocating a reward during social cooperation in a real effort task.

Questioning the Effort Hypothesis That Depressed Patients Perform Disproportionately Worse on Effortful Cognitive Tasks.

The debate over Hasher and Zacks’ effort hypothesis—that performance on effortful tasks by patients with depression will be disproportionately worse than their performance on automatic tasks—shows a need for additional research to settle whether or not this notion is “clinical lore.” In this study, we categorized 285 outpatient recipients of neuropsychological evaluations into three groups—No Depression, Mild-to-Moderate Depression, and Severe Depression—based on their Beck Depression Inventory-2 self-reports. We then compared these groups’ performances on both “automatic” and “effortful” versions of the Ruff 2 & 7 Selective Attention Test Total Speed and Total Accuracy Indices, the Digit Span subtest from the Wechsler Adult Intellectual Scale—Fourth Edition, and Trail Making Test Parts A and B, using a two-way (3 × 2) mixed multivariate analysis of variance. Patients with Mild-to-Moderate Depression or Severe Depression performed disproportionately worse than patients with No Depression in our sample on more effortful versions of only one of the four attention or executive functioning measures (Trail Making Test). Thus, these data failed to fully support a hypothesis of disproportionately worse performance on more effortful tasks. While this study failed to negate the effort hypothesis in some specific instances, particularly for use in the Trail Making Test, there is cause for caution in routinely applying the effort hypothesis when interpreting test findings in most clinical settings and for most measures.

Investigating serotonergic contributions to cognitive effort allocation, attention, and impulsive action in female rats.

Individuals must frequently evaluate whether it is worth allocating cognitive effort for desired outcomes. Motivational deficits are a common feature of psychiatric illness such as major depression. Selective serotonin reuptake inhibitors are commonly used to treat this disorder, yet some data suggest these compounds are ineffective at treating amotivation, and may even exacerbate it. Here we used the rodent Cognitive Effort Task (rCET) to assess serotonergic (5-hydroxytryptamine, 5-HT) contributions to decision-making with cognitive effort costs. The rCET is a modified version of the 5-choice serial reaction time task, a well-validated test of visuospatial attention and impulse control. At the start of each rCET trial, rats chose one of two levers, which set the difficulty of an attentional challenge, namely the localization of a visual stimulus illuminated for 0.2 or 1 s on hard versus easy trials. Successful completion of hard trials was rewarded with double the sugar pellets. Twenty-four female Long-Evans rats were trained on the rCET and systemically administered the 5-HT1A agonist 8-OH-DPAT, the 5-HT2A antagonist M100907, the 5-HT2C agonist Ro-60-0175, as well as the 5-HT2C antagonist SB 242, 084. 5-HT2A antagonism dose-dependently reduced premature responding, while 5-HT2C antagonism had the opposite effect. 8-OH-DPAT impaired accuracy of target detection at higher doses, while Ro-60-0175 dose-dependently improved accuracy on difficult trials. However, none of the drugs affected the rats' choice of the harder option. When considered with existing work evaluating decision-making with physical effort costs, it appears that serotonergic signalling plays a minor role in guiding effort allocation.

Basic Income and Social Sustainability in Post-Growth Economies

AbstractA central task in efforts to identify pathways to ecologically and socially sustainable economies is to reduce inequality and poverty while reducing material consumption, which has recently inspired future post-growth scenarios. We build a model to explore the potential of a universal basic income (UBI) to serve these objectives. Starting from the observation that post-growth trajectories can take very different forms we analyze UBI in two scenarios advanced in the literature. Comparing UBI in a “local self-sufficiency” economy to a UBI in an “automation” economy, we show that although both scenarios satisfy central sustainability criteria, the impact of a UBI would differ greatly between these contexts. Our analysis shows that a UBI is less compatible with a labor-intensive local self-sufficiency economy than a capital-intensive, high tech economy. We conclude that the feasibility and attractiveness of a UBI in a post-growth scenario depends greatly on the specific characteristics of the economy.

Working too much for too little: stochastic rewards cause work addiction

People are generally assumed to shy away from activities generating stochastic rewards, thus requiring extra compensation for handling any additional risk. In contrast with this view, neuroscience research with animals has shown that stochastic rewards may act as a powerful motivator. Applying these ideas to the study of work addiction in humans, and using a new experimental paradigm, we demonstrate how stochastic rewards may lead people to continue working on a repetitive and effortful task even after monetary compensation becomes saliently negligible. In line with our hypotheses, we show that persistence on the work task is especially pronounced when the entropy of stochastic rewards is high, which is also when the work task generates more stress to participants. We discuss the economic and managerial implications of our findings.

Working Too Much for Too Little: Stochastic Rewards Cause Work Addiction

People are generally assumed to shy away from activities generating stochastic rewards, thus requiring extra compensation for handling any additional risk. In contrast with this view, neuroscience research with animals has shown that stochastic rewards may act as a powerful motivator. Applying these ideas to the study of work addiction in humans, and using a new experimental paradigm, we demonstrate how stochastic rewards may lead people to continue working on a repetitive and effortful task even after monetary compensation becomes saliently negligible. In line with our hypotheses, we show that persistence on the work task is especially pronounced when the entropy of stochastic rewards is high, which is also when the work task generates more stress to participants. We discuss the economic and managerial implications of our findings.

Monetary and Social Incentives in Multi-Tasking: The Ranking Substitution Effect

Rankings are prevalent information and incentive tools in labor markets with strong competition for talent. In a dynamic model of multi-tasking and an accompanying experiment with financial professionals, we identify hidden ranking costs when performance in one task is incentivized and ranked while another prosocial task is not: (i) a ranking influences behavior if individuals lag behind: they spend more total effort and substitute effort in the prosocial task with effort in the ranked task; (ii) those ahead in the ranking spend less total effort and lower relative effort in the ranked task. Implications for incentive schemes are discussed.

Tournaments with Safeguards: A Blessing or a Curse for Women

Workplace tournaments are one likely contributor to gender differences in labor market outcomes. Relative to men, women are often less eager to compete and thrive less under competitive pressure. We investigate a competitive workplace environment that may produce more gender-neutral outcomes: tournaments with safeguards. In our experiments, participants take part in a tournament with a real effort task and choose whether they want to have a complimentary safeguard that guarantees higher wages for the low-ranked. As expected, we find that women are more likely than men to obtain such a safeguard. However, obtaining a safeguard comes at a cost. On average, the safeguard causes lower performance, creates a gender wage gap, and over-proportionally disadvantages women. Thus, we provide novel evidence that easing women into tournaments can backfire.

Gender Bias in Opinion Aggregation

Gender biases have been documented in areas including hiring, promotion or performance evaluations. Many of these decisions are made by committees. We experimentally investigate whether committee deliberation contributes to gender biases. In our experiments participants perform a real effort task with subjective performance and rate the task performance of other participants. In a 3 $\times$ 2 design we vary the extent to which communication among raters is possible and whether or not the experiment is gender-blind. There is little evidence of gender bias in the absence of communication or with minimal communication. By contrast, gender bias is strong and highly statistically significant under open communication. In the latter case 60 percent of ratings received by men are revised upwards after deliberation compared to only 25 percent of ratings received by women. As a consequence women are ranked on average three positions lower after deliberation. We then test two interventions for open deliberation. Randomizing the order of speaking does not reduce gender bias, but an information intervention where raters are informed of gender bias in prior sessions does.

She Could Not Agree More: The Role of Failure Attribution in Shaping the Gender Gap in Competition Persistence

In competitive and high-reward domains such as corporate leadership and entrepreneurship, women are not only underrepresented but they are also more likely to drop-out after failure. In this study, we conducted a laboratory experiment to investigate the influence of attributing failure to one of the three causal attributions - luck, effort, and ability - on the gender difference in competition persistence. Participants compete in a real effort task and then their success or failure is attributed to one of three causal attributions. We find significant gender differences in competition persistence when failure is attributed to a lack of ability, with women dropping out more. On the contrary, when suggested that failure was due to lack of luck, women’s competition persistence after failure increases relative to men. We find no gender difference when failure is attributed to a lack of effort. Our findings have important implications for designing feedback mechanisms to reduce the gender gap in competitive domains.

Gift Exchange under Sources of Uncertainty

Decision making under uncertainty depends not only on the likelihoods but also on the sources of uncertainty in terms of the degree of ambiguity, competence, and familiarity. This study goes beyond valuation experiments to examine the source dependence in the setting of gift exchange. We randomly assign 4,203 Amazon Mechanical Turk participants to different conditions, under which they receive a lottery as a gift to motivate their performance on a real effort task. These lotteries vary in both the likelihood of winning and the source of uncertainty---betting on the stock index of a familiar or an unfamiliar region. We observe a twofold pattern: The lottery with the familiar (unfamiliar) source of uncertainty motivates higher effort when the likelihood of winning is moderate to high (low). Moreover, effort exhibits more insensitivity to the likelihood of winning under the unfamiliar source compared with the familiar source. Our findings support the generalizability of source dependence in applied settings.