The Effects of Alarm System Errors on Dependence: Moderated Mediation of Trust With and Without Risk

Research on sensor-based signaling systems suggests that false alarms and misses affect operator dependence via two independent psychological processes, hypothesized as two types of trust. These two types of trust manifest in two categorically different behaviors: compliance and reliance. The current study links the theoretical perspective outlined by Lee and See (2004) to the compliance-reliance paradigm, and argues that trust mediates the false alarm-compliance relationship but not the miss-reliance relationship. Specifically, the key conditions to allow the mediation of trust are: The operator is presented with a salient choice to depend on the signaling system and the risk associated with non-dependence is recognized. Eighty-eight participants interacted with a primary flight simulation task and a secondary signaling system task. Participants were asked to evaluate their trust in the signaling system according to the informational bases of trust: Performance, process, and purpose. Half of the participants were in a high risk group and half were in a low risk group. The signaling systems varied by reliability (90%, 60%) within subjects and error bias (false alarm prone, miss prone) between subjects. Generally, analyses supported the hypotheses. Reliability affected compliance, but only in the false alarm prone group. Alternatively, reliability affected reliance, but only in the miss prone group. Higher reliability led to higher subjective trust. Conditional indirect effects indicated that individual factors of trust mediated the relationship between false alarm rate and compliance (i.e., purpose) and reliance (i.e., process), but only in the high risk groups. Serial mediation analyses indicated that the false alarm rate affected compliance and reliance through the sequential ordering of the factors of trust, all stemming from performance. Miss rate did not affect reliance through any of the factors of trust. The theoretical implications of this study suggest the compliance-reliance paradigm is not the reflection of two independent types of trust. The practical applications of this research could be to update training and design recommendations that are based upon the assumption of trust causing operator responses regardless of error bias

The Role of Trust as a Mediator Between System Characteristics and Response Behaviors

There have been several theoretical frameworks that acknowledge trust as a prime mediator between system characteristics and automation reliance. Some researchers have operationally defined trust as the behavior exhibited. Other researchers have suggested that although trust may guide operator response behaviors, trust does not completely determine the behavior and advocate the use of subjective measures of trust. Recently, several studies accounting for temporal precedence failed to confirm that trust mediated the relationship between system characteristics and response behavior. The purpose of the current work was to clarify the roles that trust plays in response behavior when interacting with a signaling system. Forty-four participants interacted with a primary flight simulation task and a secondary signaling system task. The signaling system varied in reliability (90% and 60%) within subjects and error bias (false alarm prone and miss prone) between subjects. Analyses indicated that trust partially mediated the relationship between reliability and agreement rate. Trust did not, however, mediate the relationship between reliability and reaction time. Trust also did not mediate the relationships between error bias and reaction time or agreement rate. Analyses of variance generally supported specific behavioral and trust hypotheses, indicating that the paradigm employed produced similar effects on response behaviors and subjective estimates of trust observed in other studies. The results of this study indicate that other mediating variables may offer more predictive power in determining response behaviors. Additionally, strong assumptions of trust acting as the prime mediator and operationally defining trust as a type of behavior should be viewed with caution

Vibrotactile Stimuli Parameters on Detection Reaction Times

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Signaling system designers are leveraging the tactile modality to create alarms, alerts, and warnings. The purpose of this research was to map detection reaction times (RT) toward tactile stimuli with various parameter manipulations. We employed a 3 (wave form) × 3 (inter-pulse interval) × 3 (envelope) within subjects design. The dependent measure was detection RT. Twenty participants (15 female) responded to 270 tactile stimuli. ANOVAs indicated three two-way interactions. Generally, shorter inter-pulse intervals led to quicker RT and the fade-in envelope led to longer RT, when compared to envelopes starting at the maximum amplitude. Square and sinusoidal waves tended to prompt quicker RT than the noise wave. The strength of these relationships, however, depended upon the presence of the other parameters. Designers can use the results of this study to effectively and appropriately assign tactile parameter manipulations to signals that require varied levels of response urgencies

West Africa Seed and Planting Material, No. 16

Quorum sensing (QS), where bacteria secrete and respond to chemical signals to coordinate population-wide behaviors, has revealed that bacteria are highly social. Here, we investigate how diversity in QS signals and receptors can modify social interactions controlled by the QS system regulating bacteriocin secretion in Streptococcus pneumoniae, encoded by the blp operon (bacteriocin-like peptide). Analysis of 4096 pneumococcal genomes detected nine blp QS signals (BlpC) and five QS receptor groups (BlpH). Imperfect concordance between signals and receptors suggested widespread social interactions between cells, specifically eavesdropping (where cells respond to signals that they do not produce) and crosstalk (where cells produce signals that non-clones detect). This was confirmed in vitro by measuring the response of reporter strains containing six different blp QS receptors to cognate and non-cognate peptides. Assays between pneumococcal colonies grown adjacent to one another provided further evidence that crosstalk and eavesdropping occur at endogenous levels of signal secretion. Finally, simulations of QS strains producing bacteriocins revealed that eavesdropping can be evolutionarily beneficial even when the affinity for non-cognate signals is very weak. Our results highlight that social interactions can mediate intraspecific competition among bacteria and reveal that competitive interactions can be modified by polymorphic QS systems