Objective: The objective was to conduct meta-analyses that investigated the effects of two training strategies, increasing difficulty (ID) and part-task training (PTT), on transfer of skills and the variables that moderate effectiveness of the strategies. Background: Cognitive load theory (CLT) provides a basis for predicting that training strategies reducing the intrinsic load of a task during training avail more resources to be devoted to learning. Two strategies that accomplish this goal, by dividing tasks in parts or by simplifying tasks in early training trials, have offered only mixed success. Method: A pair of complementary effect size measures were used in the meta-analyses conducted on 37 transfer studies employing the two training strategies: (a) a transfer ratio analysis on the ratio of treatment transfer performance to control transfer performance and (b) a Hedges’ g analysis on the standardized difference between treatment and control group means. Results: PTT generally produced negative transfer when the parts were performed concurrently in the whole transfer task but not when the parts were performed in sequence. Variable-priority training of the whole task was a successful technique. ID training was successful when the increases were implemented adaptively but not when increased in fixed steps. Both strategies provided evidence that experienced learners benefited less, or suffered more, from the strategy, consistent with CLT. Conclusion: PTT can be successful if the integrated parts are varied in the priority they are given to the learner. ID training is successful if the increases are adaptive. The fundamental elements of CLT are confirmed.

Objective:The aim is to establish the extent to which the high false-alarm rate of air traffic control midair conflict alerts is responsible for a "cry wolf" effect-where true alerts are not responded to and all alerts are delayed in their response. Background: Some aircraft collisions have been partly attributed to the cry wolf effect, and in other domains (health care and systems monitoring), there is a causal connection between false-alarm rate and cry wolf behavior. We hypothesized that a corresponding relationship exists in air traffic control (ATC). Method: Aircraft track and alert system behavior data surrounding 495 conflict alerts were analyzed to identify true and false alerts, trajectory type, and controller behavior. Forty-five percent of the alerts were false, ranging from 0.28 to 0.58. Results: Although centers with more false alerts contributed to more nonresponses, there was no evidence that these were nonresponses to true alerts or that response times were delayed in those centers. Instead, controllers showed desirable anticipatory behavior by issuing trajectory changes prior to the alert. Those trajectory pairs whose conflicts were more difficult to visualize induced more reliance on, and less compliance with, the alerting system. Conclusion: The high false-alarm rate does not appear to induce cry wolf behavior in the context of en route ATC conflict alerts. Application: There is no need to substantially modify conflict alert algorithms, but the conflict alert system may be modified to address difficult-to-visualize conflicts.

Findings apply to predicting effects of sleep disruption on workers in safety-critical environments, such as health care, aviation, the military, process control, and in particular, safety-critical environments involving shiftwork or long-duration missions.

The findings from this research will help inform the design of multimodal interfaces in data-rich, event-driven domains.

Two novel versions of a meta analysis were employed to assess the conditions of ongoing vehicle control task simulations in which (1) auditory presentation of an interrupting task were beneficial over visual presentations and (2) redundant (av) presentation was better than single modality presentation (providing redundancy gain). Altogether 29 studies were identified. The results revealed that the interrupting task benefited from auditory presentation, but the ongoing task (visual vehicle control task) generally did not. Performance of the visual interrupting task was slightly hindered by separation from the ongoing task. The redundancy analysis revealed that the interrupting task benefited from redundancy when it involved spatial localization and alerting and the accuracy of verbal communications; but suffered when speed of the verbal communications response was measured, and when the two visual channels were separated. Implications for multi-modal presentation of information on vehicle workstations are discussed.