Publications:

Navid Ghaffarzadegan. 2008. How a System Backfires: Dynamics of Redundancy Solution in Security, Risk Analysis 28(6): 1669 - 1687. Impact factor = 1.83

This paper elaborates Scott Sagan's hypotheses about effects of redundancy on security. I simulate and analyze a simple and generic security system as more guards are added to the system. Simulation results support two of Sagan's hypotheses and make us question the importance of the initial power of adversaries as the results show that, for any exogenous level of adversary power, the system endogenously overcompensates to a level that makes the system more susceptible to being attacked. Simulation Model in Vensim.

The first versions of this paper were presented in the International System Dynamics Conference, Boston 2007 and NAACSOS Conference, Atlanta 2007.

Navid Ghaffarzadegan, Amir T. Tajrishi. 2010. Economic Transition Management in a Commodity Market: The Case of the Iranian Cement Industry, System Dynamics Review 26(2): 139–161 . Impact factor = 1.41

This paper represents recommended policies for the Iranian Cement Industry which deals with an economic transition to market economy. Building on commodity model literature, we develop a cement price model and tailor it for testing different economic transition policies. Experimenting with the model, we suggest a specific transition policy which starts from drastic rise(s) in price before leaving the price up to the market. Simulation Model in Vensim.

The first version of this paper was presented in the International System Dynamics Conference, Boston 2007.

Navid Ghaffarzadegan, John Lyneis, George Richardson. 2010. How Small System Dynamics Models Can Help the Public Policy Process, forthcoming in System Dynamics Review. Impact factor = 1.41

Public policies often fail to achieve their intended result due to the complexity of both the environment and the policy making process. In this article, we review the benefits of using small system dynamics models to address public policy questions. First we discuss the main difficulties inherent in the public policymaking process. Then, we discuss how small system dynamics models can address policy making difficulties by examining two promising examples.

The first version was presented in the plenary session of the International System Dynamics Conference, Albuquerque 2009.

Navid Ghaffarzadegan, Laura Black, Don Greer, David Andersen. 2010. The Role of Delays and Iterations in Creating Shared Understanding in Collaborative Product Development Work Teams, Under review

This research explains how “disconnects,” or large gaps in contract baselines, can occur in complex software-intensive government initiated programs and identifies ways to reduce significant unchecked miscommunications. Disconnects are important because they can and do contribute to uncertainty over project scope and significant cost overruns, and missed deadlines, all of which threaten timely and within budget completion of quality projects that fully meet initial design expectations.

The first drafts of this paper were presented at International System Dynamics Conference, and Association for public policy analysis and management (APPAM).

Navid Ghaffarzadegan, Andrew Whitmore. 2010. Cultural Tools of Framing and Politics of Persuasion in the Persian Blogosphere, Under review

This study aims to develop an understanding of power struggles and political practices inside cyber societies, specifically blogospheres. An inductive study of the Persian blogosphere—a highly politicized, online context—is conducted through participant observation and an extensive coding of interactions (posts and comments). Our findings contradict the intuitive expectation that in a well-educated context, rational arguments would be supported with adequate evidence. However, in this context, people frequently frame their arguments by utilizing socially constructed tools of persuasion (norms, stories, and symbols). We discuss the persuasion tools by focusing on a specific controversial topic in the blogosphere.

Selected Conference Papers:

Navid Ghaffarzadegan, David Andersen. 2010. Optimal Private and Public Warning Decisions in a Dynamic Context, Working paper

A normative approach to security problems can give important insights into what the most proper security policies are for a given set of circumstances. In this paper we propose a simulation model based on Signal Detection Theory that enables the determination of optimal private and public warning decisions. Through the extended model we show that optimal solutions are sensitive to two major assumptions: sensitivity to false alarms and adversaries’ perceptions of public sensitivity. The results show that an underestimation of these effects can result in biases in optimal solutions.

The paper is presented at Association for public policy analysis and management (APPAM).

Navid Ghaffarzadegan, Thomas Stewart. 2009. Modeling the Effects of Conditional Feedback on Learning, Working paper

This study is about decision making in a series of tasks with outcome feedback. For many selection and detection problems, feedback is only available for positive decisions (e.g., if you decide to hire a candidate you get to know her true performance). In this paper, we use simulation to investigate how such “conditional feedback” affects decisions. Simulation results show the model is able to replicate two results in threshold learning: conservative threshold placement in full feedback and threshold overestimation in conditional feedback. Simulation Model in Vensim.

Different drafts of this paper are presented at the Academy of Management Conference (AOM), Society for Judgment and Decision Making (SJDM), and International System Dynamics Conference. The first drafts received the Barry Richmond Scholarship Award and Honorable Mention in Dana Meadows Student Paper Award.

Other Conference Papers are listed in the CV

Last updated: 6/10/10 by ng