Incentivizing Efficiency in Societal-Scale Cyber-Physical Systems

Lillian Ratliff

EECS Department
University of California, Berkeley
Technical Report No. UCB/EECS-2015-178
August 4, 2015

http://www2.eecs.berkeley.edu/Pubs/TechRpts/2015/EECS-2015-178.pdf

In the modernization of infrastructure systems such as energy, transportation, and healthcare systems we are seeing the convergence of three research domains: Cyber–Physical Systems (CPS), Big Data, and the Internet of Things (IoT). Indeed, new CPS technologies are are being deployed to create large sensor-actuator networks which produce massive quantities of data often in real-time which is, in turn, being used to inform everyday decision-making of the entities that engage with these large-scale infrastructure systems. As a consequence, such systems are quickly evolving into societal-scale cyber-physical systems.

The result of this increasing connectivity and interdependence is two–fold: more data is being collected, transmitted, and stored, and more actuation modalities are available, allowing new ways to influence the behavior of infrastructure systems. These new and pervasive sensing/actuation modalities present new opportunities for improving efficiency, yet they expose novel vulnerabilities. In energy CPS, for instance, smart metering technologies increase the availability of streaming data thereby enabling monetization of energy savings. Such savings can be realized by employing novel machine learning algorithms to customize offerings to consumers. On the other hand, the availability of this fine-grained consumer/system data and the increased number of access points to the broader system expose new privacy and security risks. Hence, there is a inherent efficiency-vulnerability tradeoff. This tradeoff is becoming more pronounced due to greater dependence on CPS technologies and the push towards more human-centric operations, i.e. integration of human decision-making and preferences into the closed-loop behavior of the system.

Beginning with the problem of modeling the non-cooperative agents that interact with these large-scale sociotechnical systems and thus, compete over scarce resources, we analyze the of the outcome of their strategic interactions. In particular, we create a characterization of Nash equilibria—termed differential Nash equilibria—in games on non-convex strategy spaces that is amenable to computation. We show that such non-degenerate differential Nash equilibria are structurally stable and generic thereby robust to small modeling errors and measurement noise. Introducing a planner tasked with coordinating these decision-makers, we leverage this characterization in the construction of a utility learning and incentive design algorithm. We provide convergence results in both the case where agents play according to Nash and where they play using a myopic update rule.

Narrowing our focus to the demand-side of the smart grid, we consider that the planner will capitalize on new sensing/actuation modalities in the design incentives thereby exposing the efficiency-vulnerability tradeoff. We consider privacy risks introduced by smart metering technologies that produce streaming energy consumption data. We propose a solution that combines economic and statistics tools, i.e. privacy-aware service contracts in which service is differentiated according to privacy and consumers select based on their needs and wallet. We argue that the power company has an incentive to invest in security or purchase insurance because of inefficiencies that arise due to information asymmetries and we design insurance contracts accordingly. We provide a number of qualitative insights that have the potential to be useful for informing policy and regulations in the energy ecosystem. Finally, we conclude with an overview of the contributions and a discussion of future research directions.

The contributions are the first steps towards an emerging systems theory of societal-scale cyber-physical systems in which there are many tightly coupled human-CPS decision-making loops and socioeconomic factors intricately woven into the fabric.

Advisor: S. Shankar Sastry and Pravin Varaiya


BibTeX citation:

@phdthesis{Ratliff:EECS-2015-178,
    Author = {Ratliff, Lillian},
    Title = {Incentivizing Efficiency in Societal-Scale Cyber-Physical Systems},
    School = {EECS Department, University of California, Berkeley},
    Year = {2015},
    Month = {Aug},
    URL = {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2015/EECS-2015-178.html},
    Number = {UCB/EECS-2015-178},
    Abstract = {In the modernization of infrastructure systems such as energy, transportation, 
and healthcare systems we are seeing the convergence of three research domains: 
Cyber–Physical Systems (CPS), Big Data, and the Internet of Things (IoT).
Indeed, new CPS technologies are are being deployed to create large
sensor-actuator networks which produce massive quantities of data often in
real-time which is, in turn, being used to inform everyday decision-making of
the entities that engage with these large-scale infrastructure systems. As a
consequence, such systems are  quickly evolving into societal-scale
cyber-physical systems.

The result of this increasing connectivity and interdependence is two–fold: more
 data is being collected, transmitted, and stored, and more
actuation modalities are available, allowing new ways to influence the behavior
of infrastructure systems. These new and pervasive sensing/actuation
modalities present new opportunities for
improving efficiency, yet they expose novel vulnerabilities.  
In energy CPS, for instance, smart metering 
technologies increase the availability of streaming data thereby enabling 
monetization of energy savings. Such savings can be realized by employing novel
machine learning algorithms to customize offerings to consumers. On the other
hand, the availability of this fine-grained consumer/system data and the
increased number of access points to the broader system expose new privacy and security risks. Hence, there is a inherent efficiency-vulnerability tradeoff.
This tradeoff is becoming more pronounced due to greater dependence on CPS technologies and the push towards more human-centric operations, i.e. integration of human decision-making and preferences into the closed-loop behavior of the system.  

Beginning with the problem of modeling the non-cooperative agents that interact with these large-scale sociotechnical systems and thus, compete over scarce resources, we analyze the of the outcome of their strategic
interactions. In particular, we create a characterization of Nash equilibria—termed differential
Nash equilibria—in games on
non-convex strategy spaces that is amenable to computation. We show that
such non-degenerate differential Nash equilibria are structurally stable and
generic thereby robust to small modeling errors and measurement noise. 
Introducing a planner tasked with coordinating these decision-makers, we
leverage this characterization in the construction of a utility learning and
incentive design algorithm. We provide convergence results in both the case
where agents play according to Nash
and where they play using a myopic update rule.

Narrowing our focus to the demand-side of the smart grid, we
consider that the planner will capitalize on new sensing/actuation modalities
in the design incentives thereby exposing the efficiency-vulnerability
tradeoff. We consider privacy risks introduced by smart metering technologies
that produce streaming energy consumption data. We propose a solution that combines economic and statistics tools, i.e. privacy-aware
service contracts in which service is differentiated according to privacy and
consumers select based on their needs and wallet. We argue that the
power company has an incentive to invest in security or purchase insurance
because of inefficiencies that arise due to information asymmetries and we
design insurance contracts accordingly. We provide a number of qualitative insights that have the potential to be useful for informing policy and regulations in the energy ecosystem. Finally, we conclude with an overview of the contributions and a discussion of future
research directions.

The contributions are the first steps towards an emerging systems theory of
societal-scale cyber-physical systems in which there are many tightly
coupled human-CPS decision-making loops and 
socioeconomic factors intricately woven into the fabric.}
}

EndNote citation:

%0 Thesis
%A Ratliff, Lillian
%T Incentivizing Efficiency in Societal-Scale Cyber-Physical Systems
%I EECS Department, University of California, Berkeley
%D 2015
%8 August 4
%@ UCB/EECS-2015-178
%U http://www2.eecs.berkeley.edu/Pubs/TechRpts/2015/EECS-2015-178.html
%F Ratliff:EECS-2015-178