Rachel F. Adler

Juggling on a high wire: Multitasking effects on performance

In this study, we develop a theoretical model that predicts an inverted-U relationship between multitasking and performance. The model is tested with a controlled experiment using a custom-developed application. Participants were randomly assigned to either a control condition, where they had to perform tasks in sequence, or an experimental condition, where they could discretionarily switch tasks by clicking on tabs. Our results show an inverted-U pattern for performance efficiency (productivity) and a decreasing line for performance effectiveness (accuracy). The results of this study indicate that the nature of the relation between multitasking and performance depends upon the metric used. If performance is measured with productivity, different multitasking levels are associated with an inverted-U curve where medium multitaskers perform significantly better than both high and low multitaskers. However, if performance is measured with accuracy of results, the relation is a downward slopping line, in which increased levels of multitasking lead to a significant loss in accuracy. Metaphorically speaking, juggling multiple tasks is much more difficult while balancing on a high wire, where performance mishaps can have serious consequences.

Self-interruptions in discretionary multitasking

Human multitasking is often the result of self-initiated interruptions in the performance of an ongoing task. These self-interruptions occur in the absence of external triggers such as electronic alerts or email notifications. Compared to externally induced interruptions, self-interruptions have not received enough research attention. To address this gap, this paper develops a typology of self-interruptions based on the integration of Flow Theory and Self-regulation Theory. In this new typology, the two major categories stem from positive and negative feelings of task progress and prospects of goal attainment. The proposed classification is validated in an experimental multitasking environment with pre-defined tasks. Empirical findings indicate that negative feelings trigger more self-interruptions than positive feelings. In general, more self-interruptions result in lower accuracy in all tasks. The results suggest that negative internal triggers of self-interruptions unleash a downward spiral that may degrade performance.

Measuring multitasking behavior with activity-based metrics

Multitasking is the result of time allocation decisions made by individuals faced with multiple tasks. Multitasking research is important in order to improve the design of systems and applications. Since people typically use computers to perform multiple tasks at the same time, insights into this type of behavior can help develop better systems and ideal types of computer environments for modern multitasking users. In this paper, we define multitasking based on the principles of task independence and performance concurrency and develop a set of metrics for computer-based multitasking. The theoretical foundation of this metric development effort stems from an application of key principles of Activity Theory and a systematic analysis of computer usage from the perspective of the user, the task and the technology. The proposed metrics, which range from a lean dichotomous variable to a richer measure based on switches, were validated with data from a sample of users who self-reported their activities during a computer usage session. This set of metrics can be used to establish a conceptual and methodological foundation for future multitasking studies.

The Effects of Task Difficulty and Multitasking on Performance

Multitasking is prevalent during computer-mediated work. Users tend to switch between multiple ongoing computer-based tasks either due to a personal decision to break from the current task (self-interruption) or due to an external interruption, such as an electronic notification. To examine how different types of multitasking, along with subjective task difficulty, influence performance, we conducted a controlled experiment using a custom-developed multitasking environment. A total of 636 subjects were randomly assigned into one of the three conditions: discretionary, where they were allowed to decide when and how often to switch tasks; mandatory, where they were forced to switch tasks at specific times; and sequential, where they had to perform tasks in sequence, without switching. The experimental environment featured a primary problem-solving task and five secondary tasks. The results show that when the primary task was considered difficult, subjects forced to multitask had significantly lower performance compared with not only the subjects who did not multitask but also the subjects who were able to multitask at their discretion. Conversely, when the primary task was considered easy, subjects forced to multitask had significantly higher performance than both the subjects who did not multitask and the subjects who multitasked at their discretion.

The effects of positive and negative self-interruptions in discretionary multitasking

Human multitasking is often the result of self-initiated interruptions in the performance of an ongoing task. Compared to externally induced interruptions, self-interruptions have not received enough research attention. To address this gap, this paper develops a detailed classification of self-interruptions rooted in positive and negative feelings of task progress based on responses subjects provided after completing a multitasking laboratory experiment. The results suggest that multitasking due to negative feelings is associated with more self-interruptions than those triggered by positive feelings and that more self-interruptions may produce lower accuracy in all tasks. Therefore, negative internal triggers of self-interruptions seem to unleash a downward spiral that ultimately affects performance.

Study design and protocol for My Guide: An e-health intervention to improve patient-centered outcomes among Hispanic breast cancer survivors

Breast cancer is the most commonly diagnosed non-skin cancer in women and the leading cause of death among Hispanic women living in the United States. Relative to non-Hispanic white women, Hispanic women report poorer health related quality of life (HRQoL) after treatment. Although eHealth interventions delivered via Smartphones are a viable approach to addressing supportive care accessibility issues while also integrating multidisciplinary approaches for improving HRQoL, few eHealth interventions have been developed that specifically target Hispanic breast cancer survivors (BCS). This manuscript describes the methodology of a multi-site, randomized controlled behavioral trial investigating the feasibility and preliminary efficacy of a Smartphone application aimed at improving HRQoL and cancer-specific distress among Hispanic BCS. Participants will be randomized to receive the intervention application, My Guide (psychoeducation & self-management program), or the health education control condition application, My Health (health education), for six weeks. All participants will also receive weekly telecoaching to enhance adherence to both control and intervention conditions. We will measure the studys primary outcomes, general and disease-specific HRQoL and cancer-specific distress, at three time points: prior to, immediately after the intervention, and eight weeks after initial application use. My Guide may have the potential to improve HRQoL, and to address issues of limited access to supportive care among Hispanic women recovering from breast cancer treatment.

Towards new metrics for multitasking behavior

In this paper we propose new metrics to investigate computer-based multitasking behavior. These metrics range from a very lean dichotomous variable to a very rich measure based on switches that combines user, task and technology considerations. We demonstrate how to calculate these measures with an exploratory study based on self-reported user logs. The development of new metrics to research multitasking behavior lays the foundation to incorporate this variable in future studies of human-computer interaction.

Enhancing future K-8 teachers’ computational thinking skills through modeling and simulations

It is now required for teachers to incorporate computational thinking (CT) into their science classes. Our research modifies the existing structure of a science methods course for preservice teachers to include CT via modeling and simulations. In the first study, preservice teachers were introduced to the basics of coding through an Hour of Code tutorial, followed by an exercise where they programmed an animated model of the solar system using Scratch. In the second study, we created a web-based simulation to visualize Newton’s second law of motion (F = ma) with a dynamic graph feature. The simulation is a race between two cars with interactive settings that the user can change, such as changing the mass and force of each car. Results from both studies reveal that after completing the exercises, preservice teachers learned the material effectively, felt that CT exercises would be beneficial in K-8 education, and plan to incorporate CT into their future classrooms.

Designing an mHealth application to bridge health disparities in Latina breast cancer survivors: a community-supported design approach

ABSTRACT Latina breast cancer patients in the USA report significantly worse cancer-related symptom burden and health-related quality of life than non-Hispanic whites. However, health literacy (e.g. knowledge about cancer, coping skills and communication) has been found to improve quality of life. In this paper, we present a case study of the methodology used to design Mi Guía (My Guide), a mobile application that aims to improve symptom burden and health-related quality of life among Hispanic women who have completed active treatment for breast cancer by increasing their health literacy. We developed a community-supported approach to building the application, which involved: (1) eliciting feedback from community leaders such as support group organizers and facilitators who are bilingual in Spanish and English, prioritize patients’ preferences and best interests and have a unique knowledge of the women and their needs; (2) conducting a formal evaluation of design principles based on previous interaction design research and user responses; (3) incorporating feedback from potential future users. In this paper, we discuss our methodology, and the challenges and benefits of this approach. We believe that future studies that aim to develop mobile technologies for underserved populations may benefit from a community-supported approach to design.

A comparison of performance and preference on mobile devices vs. desktop computers

Smartphones and desktop computers are ubiquitous in todays world. Due to the improved computing power and high portability of smartphone devices, users are performing more sophisticated tasks on their smartphones. This study compares the performance of a web-based task on a desktop computer with a mobile-based task on a smartphone. In addition, we have compared the overall user experience and preference across the two devices. In order to achieve this, we created a mobile-based word game for an Android mobile platform and a web-based version of the same word game for a browser platform. Sixty participants were instructed to complete the tasks on both devices. Our results show that while performance on the computer-based game was significantly better than performance on the mobile-based game, people preferred to play on the smartphone rather than the desktop computer. People preferred smartphones over desktop computers on account of their touch-screen features, portability and ease of use, even though they actually performed the task more efficiently on the desktop computers.