Roumen Vragov

Roumen Vragov

About

48
Publications
4,428
Reads
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400
Citations

Publications

Publications (48)
Article
Search engines, blogs, social media, and other high-traffic web sites and mobile apps are increasingly involved in sales through the ads they display, yet it is not clear how these ads should be chosen and paid for in the most optimal way. We describe three different paths we are taking in an effort to make this choice more informed. The first expl...
Article
This article uses the design science approach and a semi-field experiment to explore the differences between a laboratory and an on-line version of an electronic voting mechanism that allows citizens to express their preference intensities as well as to be compensated in case their preferred alternative is not chosen. The authors find that particip...
Article
This paper develops a model of buyer (consumer) and seller (advertiser) strategic behavior in sponsored search auctions. Through its various extensions, the model is able to predict the effect of different ranking and payment policies on auction performance in terms of consumer surplus as well as advertisers’ and search engine profits. The theoreti...
Chapter
The use of computer algorithms by human traders in markets has been steadily increasing. These electronic agents or proxies vary in terms of purpose and complexity, however, most of them first require some input on the part of the human trader and then perform the rest of the trading task autonomously. This paper proposes a theoretical model of hum...
Article
Currently many auction websites directly or indirectly provide support for the use of automated proxies or agents. Buyers can use proxies to monitor auctions and bid at the appropriate time and with the appropriate bid price, sellers can use proxies to set prices or negotiate deals. Proxy complexity varies, however most proxies first require some i...
Article
Full-text available
New forms of implicit consumer collaborations in online communities and social networks influence demand preferences as consumers themselves increasingly participate in creating cultural products that both complements and competes with firm offerings. Although research findings on these issues vary, strong evidence from both theoretical and empiric...
Article
Recent developments in information and communication technologies (ICTs) can change the way strategic organizational decisions are negotiated and voted upon. We propose an analytical framework that investigates the effect of such technologies on the costs of the decision-making process in organizations by incorporating a technology variable in an a...
Article
Full-text available
There is disagreement in the auction literature on the question of whether dynamic Buy-It-Now (BIN) prices can increase the efficiency of online auctions, compared to static BIN price auctions. In a previous paper (Vragov et al. 2010), we reported experimental evidence that suggested, contrary to the current theoretical auction literature, that dyn...
Article
Full-text available
We propose a market based design for trading component-based software products bundled with reuse licenses that allows clients to customize software solutions onsite by reusing and reintegrating components across software systems using their own software development platforms. Using economic experiments in the laboratory with IT professionals we fi...
Article
Differential auction-barter (DAB) model augments the well-known double auction (DA) model with barter bids so that besides the usual purchase and sale activities, bidders can also carry out direct bartering of items. The DAB model also provides a mechanism ...
Chapter
In addition to helping consumers navigate the web search engines offer a new kind of e-service known as sponsored search. A search engine provides an auction interface to advertisers that allows them to be included in a list of sponsored links. Consumers then search the list to find the best deal. This paper uses a version of traditional consumer p...
Article
We examine theoretically and experimentally how competitive contribution-based group formation affects incentives to free-ride. We introduce a new formal model of social production, called a “Group-based Meritocracy Mechanism” (GBM), which extends the single-group-level analysis of a Voluntary Contribution Mechanism (VCM) to multiple groups. In a G...
Article
Full-text available
Several studies have shown that on-line consumer-to-consumer (C2C) auctions operate below their revenue and efficiency potential. From a theoretical perspective, dynamic prices should improve auction performance, but it is unclear whether this is so in practice. Experiments with economically motivated human subjects tested the benefits of using dyn...
Article
Purpose and approach – We examine theoretically and experimentally how unequal abilities to contribute affect incentives and efficiency when players compete for membership in stratified groups based on the contributions they make. Players have either a low or a high endowment. Once assigned to a group based on their group contribution, players shar...
Article
We study the impact of dynamic environment of eBay auctions on bidding behavior. Due to high-speed Internet and practically costless search possibilities, bidding behavior is no longer a function of characteristics of a single auction but depends on ...
Article
The recent consumer-to-consumer (C2C) Internet auction boom at eBay, Yahoo, Amazon, and other sites has added new theoretical challenges to the science of auctions. This paper uses experiments with economically-motivated human subjects to measure the operational efficiency of decentralized Internet auction mechanisms as they compare to centralized...
Chapter
In addition to helping consumers navigate the web search engines offer a new kind of e-service known as sponsored search. A search engine provides an auction interface to advertisers that allows them to be included in a list of sponsored links. Consumers then search the list to find the best deal. This paper uses a version of traditional consumer p...
Chapter
In addition to helping consumers navigate the web search engines offer a new kind of e-service known as sponsored search. A search engine provides an auction interface to advertisers that allows them to be included in a list of sponsored links. Consumers then search the list to find the best deal. This paper uses a version of traditional consumer p...
Conference Paper
There is disagreement in the auction literature on the question of whether dynamic Buy-It-Now (BIN) prices can increase the efficiency of online auctions. We report results from an experimental study with economically motivated subjects that compares the standard online auction format currently used on eBay with a new auction format (Online Linear...
Article
New forms of implicit consumer collaborations in online communities and social networks influence demand preferences as consumers (1) increasingly exchange information about products and providers (thus reducing information asymmetry) and (2) increasingly participate in the creation of cultural goods themselves by contributing user-generated conten...
Article
Several studies have shown that Consumer-to-consumer (C2C) auctions operate below their revenue and efficiency potential. From a theoretical perspective, most auction researchers agree that dynamic prices should improve the performance of these auctions, but it is still unclear whether dynamic prices can achieve significant benefits in practice. Th...
Article
Digital culture products are easily reproduced, easily distributed, and subject to boundless modification, extension and recombination. This sets the stage for the emergence of markets for co-production of cultural content. This paper studies two new market structures using two different licensing arrangements. First, we consider a consumer market...
Article
We examine theoretically and experimentally how a society's grouping and stratification rules affect incentives and efficiency, and compare meritocratic and ascriptive grouping. We present a multi-level model of social production, and extend the usual single-group-level analysis of cooperation to a broadly defined system, in which individuals compe...
Article
This paper presents a mathematical model that analyzes the rational incentives involved in providing an informative evaluation for a knowledge management system when the evaluation has some consequences for the evaluator. The analysis is carried out in the context of the peer review process that is currently used to determine which articles are pub...
Article
Recent developments in Information and Communication Technologies (ICT) have improved the decision-making within the parameters of existing political tradition and can also challenge fundamental assumptions about the organization of democratic governments. The three broad categories of ICTs based on interaction between governments and citizens incl...
Article
In addition to helping consumers navigate the web search engines offer a new kind of e-service known as sponsored search. A search engine provides an auction interface to advertisers that allows them to be included in a list of sponsored links. Consumers then search the list to find the best deal. This paper uses a version of traditional consumer p...
Conference Paper
We have shown in a previous study that selling content-transmutation rights to consumers increases total surplus of both producers and consumers of digital products. Our results were conditional on the absence of piracy. There has been some research on the effect of online piracy in traditional content markets that do not consider consumer transmut...
Article
While existing research on peer-to-peer (P2P) file-sharing services has increased our understanding in many respects, it has not yet supplied a comprehensive theoretical framework that explains business failures of P2P file-sharing network service models. We develop such an analytical model and base it on seven specific market constraints – technic...
Conference Paper
Full-text available
Online auctions are inherently dynamic. Online auction designs that internalize temporal changes in the economic environment are generally expected to perform better than static designs. This is because providing opportunities for both buyers and sellers to inform each other about preference changes over time can increase market transparency and le...
Article
Full-text available
We use a laboratory experiment to study the extent to which investors’ choices are affected by limited loss deduction in income taxation. We first compare investment behavior in the no tax baseline to a tax control setting, in which the income from investments is taxed. We find that investors significantly reduce their risk-taking as predicted by t...
Article
Full-text available
A new mechanism that substantially mitigates social dilemmas is examined theoretically and experimentally. It resembles the voluntary contribution mechanism (VCM) except that in each decision round subjects are ranked and then grouped according to their public contribution. The game has multiple mostly asymmetric, Pareto-ranked pure-strategy equili...
Article
Full-text available
The traditional double-blind peer review process currently used to determine which articles are published in scientific journals is far from perfect. This article argues that the Internet can provide us with a better way to judge article quality using the opinion of every reader rather than that of only a couple of reviewers. The article offers a r...
Article
Recent research on the usage of electronic markets in Digital government has mostly focused on the government's Executive branch. The paper discusses three conceptual concerns that obstruct the broader application of electronic market mechanisms to the Legislative branch of the government instead. A systematic examination of these concerns shows th...
Article
Demand reduction in Uniform-price and English auctions are strategic reactions by participants to reduce price and thus increase potential profits. Laboratory experiments similar to the field experiments performed by List and Reiley (Am. Econ. Rev. 2000; 9 (4): 961-972) in which two individuals with demands for two units vie for two units through a...
Article
Full-text available
This paper uses modified economic growth theory to compare and contrast two currently available ways of digital content distribution: the client-server model and the peer-to-peer (P2P) model. We describe a monopolistic pricing scheme for distributing digital content over P2P networks that rewards peer users who actively participate in the distribut...
Conference Paper
The advances in communication technology have allowed us to create fully automated markets that can function twenty-four hours a day using software agents as proxies to decrease transaction costs and increase efficiency. In this paper I examine the short-term and long-term behavioral effects of these agents on human market participants using experi...
Conference Paper
Active citizen participation facilitated by information technology can have profound implications for democracy and civic discourse. In this paper we describe a continuum of tools that encourage active participation by citizens. We use a comprehensive review of the web-sites of the 50 States of the U.S. to chart the current position of the country...
Conference Paper
Most consumer-to-consumer Internet auctions are isomorphic to the English auction. Bids in these auctions are visible to all participants, and prices are always ascending. The success of these auctions have puzzled auction theorists because many of the procedures used in these auctions encourage collusion among buyers that leads to lower revenues f...
Conference Paper
Full-text available
This paper describes a usage-based pricing scheme for distributing digital content over peer-to-peer networks that rewards peer users who actively participate in the distribution process. We present a dynamic distribution model that is used to compare centralized, client-server distribuition with peer-to-peer network distribution. The conventional...
Conference Paper
Full-text available
A fast-growing body of literature in information systems research as well as in other disciplines has examined peer-to-peer (P2P) filesharing from various perspectives, but has failed so far to offer a comprehensive analytic framework that would allow us to explain why the market has not yet produced any significant commercially successful P2P serv...
Article
During the last few years pedagogical philosophy has been trying to incorporate lessons from active learning theory. While most practitioners agree that active learning is useful they still lack a diverse set of tools to incorporate it in the classroom. This article describes a methodology for including real-time laboratory experiments in the regul...
Article
Most consumer-to-consumer Internet auctions are isomorphic to the English auction. Bids in these auctions are visible to all participants, and prices are always ascending. Using the institutional analysis approach, this article identifies three specific online auction rules that facilitate implicit collusion among buyers. The use of these rules oft...
Conference Paper
Developing sufficiently intelligent Marketbots is still a daunting task. The future, in which most boring and repeating transactions will be performed by automated proxies, is not very far. There already is a growing market for Marketbots, and who knows, one day Marketbots will be trading in that market as well.
Article
Purpose and approach: We examine theoretically and experimentally how unequal abilities to con- tribute affect incentives and efåciency when players compete for membership in stratiåed groups based on the contributions they make. Players have either a low or a high endowment. Once assigned to a group based upon the contribution they have made, play...
Article
Full-text available
The MHP technical standard allows TV viewers to interact directly with the broadcasted content and therefore be able to choose which commercials they would like to watch. This article outlines the basic conceptual features of an interactive application that can be used by TV networks to increase the efficiency of advertising. The application allows...

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Projects

Project (1)
Project
Cloud computing and the cloud services market have advanced in the past ten years. Cloud services now include most information technology (IT) services from fundamental computing services to more cutting- edge artificial intelligence (AI) services. Accordingly, opportunities have emerged for research on the design of new market features to improve the cloud services market to benefit providers and users. In this project, we aim to design and evaluate new market features of marketplaces, platforms and intermediaries for cloud computing services.