Phd Dissertation

Human-centered computing and the future of work : lessons from mechanical turk and turkopticon, 2008-2015

Publication Date

June 30, 2015

Areas of Expertise

Abstract

Online labor markets such as Amazon Mechanical Turk (AMT), Uber, and TaskRabbit are contributing to rapid changes in the nature of work for hundreds of thousands of workers. These markets create significant new economic opportunities, but most currently treat workers as second-class citizens. Take-home pay is often low compared to similar work in traditional employment arrangements, and workers have limited means of influencing market design or management practice. This makes it hard for workers to create reliable livelihoods from the opportunities these markets present. This dissertation uses AMT, an online labor market for small information tasks, as a case through which to examine the consequences of treating workers as second-class citizens, to argue that future platform designs and management practices should treat workers as central stakeholders, and to develop theory and method for doing so. The central argument of the dissertation is that workers’ concerns should be more substantively and systematically addressed in the design and operation of online labor markets. Five messages elaborate this argument. First, in online labor markets, some workers are casual or transient, while others are professionals, providing significant and reliable value to customers and relying on income earned in the market to meet basic needs. Second, workers who rely on income earned through online labor markets should be considered first-class stakeholders, alongside customers and shareholders. Third, workers in online labor markets are rarely the narrowly self-interested profit maximizers of classical economic theory. Workers can be better understood as “situatedly rational” actors: human beings with incomplete information and finite cognitive capabilities whose actions and preferences are shaped by many factors, including rules, norms, and expectations. Fourth, online labor markets are not monolithic, perfectly competitive markets but parts of polycentric economic systems composed of complexly interlinked action situations characterized by imperfect competition and incomplete information. Fifth, institutions supporting crowd work research should develop an interdisciplinary practice-oriented agenda to understand the consequences of current online labor market designs and practices, and to develop new designs and practices that incorporate workers who rely on market income as central stakeholders.

Suggested Citation
MICHAEL SILBERMAN (2015) Human-centered computing and the future of work : lessons from mechanical turk and turkopticon, 2008-2015. PhD Dissertation. UC Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/17uq3m8/alma991017757829704701.

working paper

Impacts of Motor Vehicle Operation on Water Quality in the United States - Clean-up Costs and Policies

Publication Date

January 1, 2007

Abstract

This paper investigates the costs of controlling some of the environmental impacts of motor vehicle transportation on groundwater and on surface waters. We estimate that annualized costs of cleaning-up leaking underground storage tanks range from $0.8 billion to $2.1 billion per year over ten years. Annualized costs of controlling highway runoff from principal arterials in the US are much larger: they range from $2.9 billion to $15.6 billion per year over 20 years (1.6% to 8.3% of annualized highway transportation expenditures.) Some causes of non-point source pollution were unintentionally created by regulations or could be addressed by simple design changes of motor vehicles. A review of applicable measures suggests that effective policies should combine economic incentives, information campaigns, and enforcement, coupled with preventive environmental measures. In general, preventing water pollution from motor vehicles would be much cheaper than cleaning it up.

Phd Dissertation

Electronic waste management in California : consumer attitudes toward recycling, advanced recycling fees, "green" electronics, and willingness to pay for e-waste recycling

Publication Date

June 30, 2006

Author(s)

Areas of Expertise

Suggested Citation
Hilary Nixon (2006) Electronic waste management in California : consumer attitudes toward recycling, advanced recycling fees, "green" electronics, and willingness to pay for e-waste recycling. PhD Dissertation. UC Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/17uq3m8/alma991034707529704701.

Phd Dissertation

Economic analysis of aircraft and airport noise regulations

Publication Date

January 1, 2006

Author(s)

Abstract

The aviation industry has sought to address the negative externality of aircraft noise using a variety of approaches, but there has been little theoretical work to date encompassing both the market implications and the social optimality of air transportation noise policy. This dissertation develops simple theoretical models to analyze the effects of noise regulation on an airline’s scheduling, aircraft ‘quietness’, and airfare choices. Monopolistic and duopolistic airline competition are modelled, and two types of noise limits are considered: maximum cumulative noise from aircraft operations and noise per aircraft operation. As expected, tighter noise limits, which reduce community exposure to noise, also cause airlines to reduce service frequency and raise fares, which hurts consumers. Welfare analysis investigates the social optimality of noise regulation, taking into account the social cost of exposing airport communities to noise damage, as well as consumer surplus and airline profit. Numerical simulations show that the type of noise limit has a significant effect on the magnitude of the first-best and second-best optimal solutions for service frequency, cumulative noise, and aircraft size and level of quietness. Furthermore, the numerical analyses suggest that under the more realistic second-best case, the cumulative noise limit might be a preferable policy instrument over the per-aircraft noise limit. In the monopoly’s parameter space exploration, welfare is found to be slightly higher, cumulative noise is lower, and the fare is slightly lower when the planner controls cumulative noise rather than per-aircraft noise. In the duopoly case, when the per-aircraft limit yields greater welfare than the cumulative limit, the per-aircraft limit offers only modest welfare gains above the levels achieved with the cumulative limit. But when the cumulative limit yields greater welfare than the per-aircraft limit, the cumulative limit offers substantial welfare gains above the levels achieved with the per-aircraft limit. The effects of noise taxation and the optimal level of noise taxes are also investigated with the duopoly model; the analysis shows equivalence between noise taxation and the cumulative noise limit.

Suggested Citation
Raquel Girvin (2006) Economic analysis of aircraft and airport noise regulations. Ph.D.. University of California, Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/74dcdl/alma991035092979904701 (Accessed: October 14, 2023).

published journal article

Aircraft Navigation in GNSS-Denied Environments via Radio SLAM With Terrestrial Signals of Opportunity

IEEE Transactions on Intelligent Transportation Systems

Publication Date

October 1, 2024

Author(s)

Zaher Kassas, Nadim Khairallah, Joe Khalife, Chiawei Lee, Juan Jurado, Steven Wachtel, Jacob Duede, Zachary Hoeffner, Thomas Hulsey, Rachel Quirarte, RunXuan Tay

Abstract

A radio simultaneous localization and mapping (radio SLAM) framework enabling aircraft navigation with terrestrial signals of opportunity (SOPs) is presented and experimentally validated. The framework does not assume availability of global navigation satellite system (GNSS) signals. Instead, it assumes the aircraft to have an initial estimate of its own states, after which it navigates by exploiting pseudorange measurements extracted from terrestrial SOPs, while estimating the states of the aircraft simultaneously with the SOPs’ states. Two radio SLAM frameworks are presented: (i) tightly-coupled SOP-aided inertial navigation system (INS) and (ii) utilizing a Wiener process acceleration (WPA) dynamical model for the aircraft’s dynamics instead of the INS. Results from four flight runs on a US Air Force C-12 aircraft, equipped with an altimeter and an industrial-grade inertial measurement unit (IMU), are presented. The flight runs took place over semi-urban (SU), urban (U), and rural (R) regions in California, USA; while exercising different aircraft maneuvers: holding (H), descending (D), and grid (G). Different a priori conditions of the SOPs’ positions were studied: from all unknown, to some known, to all known. In all cases, the SOPs’ clock error states (bias and drift) were unknown and estimated alongside the aircraft’s states. The results consistently demonstrated the promise of real-world aircraft navigation via radio SLAM, yielding bounded errors along trajectories of tens of kilometers. The three-dimensional (3–D) position root-mean squared errors (RMSEs) are summarized next, where N denotes the number of SOPs exploited along the trajectory: (1) SU, H, INS-SOP, N=6
 , 56.7 km in 8.5 minutes, maximum altitude of 5,577 ft: 43.27 m with all unknown and 10.14 m with all known; (2) U, H, INS-SOP, N=6
 , 72.7 km in 12.9 minutes, maximum altitude of 5,906 ft: 89.82 m with all unknown and 16.97 m with all known; (3) SU, D, WPA-SOP, N=18
 , 111.9 km in 20.0 minutes, maximum altitude of 6,234 ft: 36.42 m with all unknown and 18.62 m with all known; and (4) R, G, WPA-SOP, N=32
 , 78.4 km in 13.8 minutes, maximum altitude of 7,546 ft: 67.01 m with all unknown and 25.65 m with all known.

Suggested Citation
Zaher M. Kassas, Nadim Khairallah, Joe J. Khalife, Chiawei Lee, Juan Jurado, Steven Wachtel, Jacob Duede, Zachary Hoeffner, Thomas Hulsey, Rachel Quirarte and RunXuan Tay (2024) “Aircraft Navigation in GNSS-Denied Environments via Radio SLAM With Terrestrial Signals of Opportunity”, IEEE Transactions on Intelligent Transportation Systems, 25(10), pp. 14164–14182. Available at: 10.1109/TITS.2024.3405908.