Current Research


   Emergence of Networks and Market Institutions in a Large
   Virtual Economy
, with Daniel Friedman and Matthew Baumer  
We analyze a complete set of transactions from an on-line barter marketplace. We construct trader and goods networks, and track them over time using network-theoretic metrics such as node strength, assortativity, betweenness and closeness. The trading platform was designed to make barter exchange as attractive as possible; money was not part of the design and all players were created equal. Yet, within weeks, several specific goods emerged as media of exchange, and various specialized traders appeared. Eventually trade was predominantly money-mediated and market-makers played a major role. Our results illustrate how network analysis can capture the spontaneous emergence of economic institutions.
Working Paper (pdf)
  

  Estimating the Effect of Windfall Gains on Economic Behavior:  
  Evidence from a Large Online Marketplace
 . 

   Aggregate Dynamics in a Large Virtual Economy: Prices and Real
   Activity in Team Fortress 2, with Matthew Baumer 
We examine economic activity in a large virtual economy which features decentralized barter as the sole exchange institution available to the participants. We find that certain goods emerge endogenously which act as media of exchange. Our analysis includes estimation of spot exchange rates between these numerous money goods and we develop a methodology which allows us to price all goods measured in an endogenous numeraire and track inflation. We calculate nominal growth and perform a decomposition it and conclude that a steadily increasing proportion of nominal growth is due to growth in per capita real wealth. We find that devaluation of a currency relative to other currencies tends to be associated with a decrease in the price of items typically denominated in that currency, possibly indicative of nominal rigidities. We also find that announcements made by the economic planners can induce speculation leading to short-lasting asset price bubbles in the markets for the goods relevant to the announcement.
  Working paper available upon request.



  Stability in Competition? Hotelling in Continuous Time
    with Liam Rose
We study Hotelling's classic location model in continuous time with flow payoffs accumulated over time and the price dimension made explicit. In an experimental setting, subjects chose price and location in treatments varying only by the timing of the game, which ranges for a discrete, staged game to instantaneous adjustment on either dimension. We find that the principle of minimum differentiation generally holds, with little distance between subjects in location decisions. We also show that there is relatively low stability in the competition between subjects, as difficulties in finding a Nash equilibrium in theoretical work are borne out in our results. Our data also support literature that the ability to respond quickly increases cooperation.
   Working Paper (pdf)  -  Presentation Deck (pdf)

   Web Appendix
    
Instructions: Discrete TimeContinuous Time
    Video Instruction Sup. DiscreteContinuous SlowContinuous Instant


  Additional Hotelling Experiments
  • Continuing the work in "Hotelling in Continuous Time" (above) we intend to investigate quadratic transport cost. 
  • Continuing the work in "Continuous Differentiation: Hotelling Revisits the Lab" (below) we intend to extend this research by investigating the components of continuous and discrete time that have lead to this distinctive result. There are two important features that differentiate continuous from discrete time; first, subjects are able to move asynchronously; and secondly, subject interaction is intensified. Regarding the first feature, in our discrete time treatment subjects selected locations simultaneously. In Monte Carlo simulations of automated agents playing myopic best response and relocating simultaneously, no equilibrium emerges. However, when these automated agents take turns relocating, the Nash equilibrium does appear. I plan additional treatments that blur the lines between continuous and discrete time thereby gaining deeper insight into these distinctions.
  • We are also developing software to implement Salop's circle model in the lab.





Published


    with second coauthor Dan Friedman
    Dec 2015 Journal of the Economic Science Association (JESA)
We investigate experimentally the impact of continuous time on a four-player Hotelling location game. The static pure strategy Nash equilibrium (NE) consists of firms paired-up at the first and third quartiles of the linear city. In repeated simultaneous move games (discrete time grid), we fail to obtain convergence to this distinctive NE, as have previous studies. However, with asynchronous moves in continuous time treatments, the NE clearly emerges.
 PDF  ·  Data and Code (zip)


    
Software for Continuous Game Experiments
    with James Pettit, Dan Friedman and Ryan Oprea
ConG is software for conducting economic experiments in continuous and discrete time. It allows experimenters with limited programming experience to create a variety of strategic environments featuring rich visual feedback in continuous time and over continuous action spaces, as well as in discrete time or over discrete action spaces. Simple, easily edited input files give the experimenter considerable flexibility in specifying the strategic environment and visual feedback. Source code is modular and allows researchers with programming skills to create novel strategic  environments and displays. 




 

     
        
Contact


CurtisKephart@gmail.com

mobile: 646 770 2012

New York University Abu Dhabi (NYUAD)
Building A5, Rm. 179
PO Box 129188
Abu Dhabi,
United Arab Emirates



  Curtis Kephart




Research Positions


       
        New York University Abu Dhabi, 2016 to present

        Postdoc and Lab Manager - Dan Friedman, LEEPS Lab  2015-2016

       Graduate Student Researcher - Dan Friedman, LEEPS Lab 
Summer 2011, Winter 2012, Summer 2012, Fall 2013, Summer 2013, Winter 2013, Fall 2014. Active in the lab since 2010. 

Lab Manager at LEEPS Lab ~ Summer 2012 - May 2016
UC Santa Cruz' Learning and Experimental Economics Project Laboratory. 
The experimental economics laboratory on campus. 
Developers of ConG and Redwood economics experiment platforms.





Teaching



Graduate Student Instructor Positions
Econ 113 - Introduction to Econometrics - Summer 2013

Teaching Assistant Positions
Introduction to Microeconomics (Econ 1) - Prof. KC Fung - Winter 2010
Marketing (Econ 161) - Prof. Mary Flannery - Spring 2010
Mathematics for Economists II (Econ 11B) - Prof. Luba Petersen - Summer 2010
Intermediate Macroeconomics (Econ 100B) - Prof. Aspen Gorry - Fall 2010
Marketing (Econ 161) - Prof. Mary Flannery - Winter 2011
Introduction to Econometrics (Econ 113) - Prof. Carlos Dobkin - Spring 2011
Introduction to Econometrics (Econ 113) - Prof. Susan Peterson - Summer 2011
Intermediate Macroeconomics (Econ 100B) - Prof. Aspen Gorry - Fall 2011
Introduction to Econometrics (Econ 113) - Prof. Carlos Dobkin - Spring 2012
Introduction to Microeconomics (Econ 1) - Prof. Nick Lovett - Summer 2012
Intermediate Macroeconomics (Econ 100B) - Prof. Johanna Francis - Fall 2012
Intermediate Macroeconomics (Econ 100B) - Prof. Johanna Francis - Winter 2014
Business Strategy (Econ 136) - Prof Bob Baden - Spring 2014

Reader
         Advanced Maths for Economics (Econ 210B) Prof. Ken Kletzer - Fall 2010



Awards and Honors


Graduate Awards
Regent's Fellowship, Economics Department, Fall 2009
Teaching Assistant Excellence Award, Econ Dept, for Marketing, Spring 2010
Teaching Assistant Excellence Award, Econ Dept, for Econometrics, Spring 2011
Teaching Assistant Excellence Award, Econ Dept, for Econometrics, Spring 2012
Outstanding Teaching Assistant (UCSC Campus-wide Award) 2012-2013
UCSC Economics Department tuition fellowship - Spring 2013

Undergraduate Awards
Department Honors, Economics Department, UCSC 2003
College Honors, Adlai Stevenson College at UCSC 2003
Graduated with B.A. in three years. 











Contact


Contact