4,850 research outputs found

    TRIDEnT: Building Decentralized Incentives for Collaborative Security

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    Sophisticated mass attacks, especially when exploiting zero-day vulnerabilities, have the potential to cause destructive damage to organizations and critical infrastructure. To timely detect and contain such attacks, collaboration among the defenders is critical. By correlating real-time detection information (alerts) from multiple sources (collaborative intrusion detection), defenders can detect attacks and take the appropriate defensive measures in time. However, although the technical tools to facilitate collaboration exist, real-world adoption of such collaborative security mechanisms is still underwhelming. This is largely due to a lack of trust and participation incentives for companies and organizations. This paper proposes TRIDEnT, a novel collaborative platform that aims to enable and incentivize parties to exchange network alert data, thus increasing their overall detection capabilities. TRIDEnT allows parties that may be in a competitive relationship, to selectively advertise, sell and acquire security alerts in the form of (near) real-time peer-to-peer streams. To validate the basic principles behind TRIDEnT, we present an intuitive game-theoretic model of alert sharing, that is of independent interest, and show that collaboration is bound to take place infinitely often. Furthermore, to demonstrate the feasibility of our approach, we instantiate our design in a decentralized manner using Ethereum smart contracts and provide a fully functional prototype.Comment: 28 page

    The crowd as a cameraman : on-stage display of crowdsourced mobile video at large-scale events

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    Recording videos with smartphones at large-scale events such as concerts and festivals is very common nowadays. These videos register the atmosphere of the event as it is experienced by the crowd and offer a perspective that is hard to capture by the professional cameras installed throughout the venue. In this article, we present a framework to collect videos from smartphones in the public and blend these into a mosaic that can be readily mixed with professional camera footage and shown on displays during the event. The video upload is prioritized by matching requests of the event director with video metadata, while taking into account the available wireless network capacity. The proposed framework's main novelty is its scalability, supporting the real-time transmission, processing and display of videos recorded by hundreds of simultaneous users in ultra-dense Wi-Fi environments, as well as its proven integration in commercial production environments. The framework has been extensively validated in a controlled lab setting with up to 1 000 clients as well as in a field trial where 1 183 videos were collected from 135 participants recruited from an audience of 8 050 people. 90 % of those videos were uploaded within 6.8 minutes

    The Impact Of Online Sponsored Search Advertising On Consumer And Seller Strategies

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    Sponsored search advertising has emerged as an important and significant forum for advertisers, accounting for 40% of all advertising spending online. The unique features of sponsored search advertising - the nature of consumer search as well as the pricing mechanisms employed - differentiate it from traditional advertising formats, and raise many interesting questions regarding consumers' search and purchase behavior, sellers' advertising strategies, and the ensuing market dynamics. However, despite the robust growth in sponsored search advertising, research on its implications is limited. My dissertation, comprising three essays, seeks to fill this gap. In addition to examining the effects of sponsored search advertising on consumers and sellers, I also investigate the validity of theories developed for traditional media in an emerging online sponsored search context. The first essay focuses on the impact of a seller's sponsored search advertising strategies, including its rank in the sponsored listing, the unique selling proposition (USP) employed in its advertisement text/creative, and competitive market dynamics on the performance of the focal seller's advertisement. Drawing upon prior research on consumer search and directional markets, I propose a model of the consumer search process in the sponsored search context and conduct an empirical study to test the research model. The results validate the research hypothesis that the search listing can act as a consumer filtering mechanism and competitive intensity within adjacent ranks has a significant impact on the seller's performance. The second essay employs consumer search and quality signaling theories from information systems, marketing, and economics to understand the impact of the informational cues contained in the sponsored search listing about sellers' relative advertising expenditure on consumer search and purchase behavior. Contrary to conventional wisdom, I find that the unique format of the sponsored search listing significantly increases the strength of the advertising signal vis-ร -vis the price signal. In addition, I find that the risk attitude of consumers has a significant impact on the valence of these different information cues in the online setting. The third essay examines market outcomes in directional markets such as sponsored search and comparison shopping advertising. Specifically, I focus on comparison shopping advertising where advertising not only informs consumers about price and quality but also directs consumer search. I find that the relationship between a firm's price, quality, and advertising intensity in this market is strikingly different from that in traditional markets, a result attributable to the differential impact of price and quality on an advertiser's conversion rates and profit margins. Overall, these studies provide crucial insights into consumer behavior in online sponsored search markets. These findings have significant implications for firms, as well as for the market makers. Insights from these studies will enable practitioners to develop appropriate advertising strategies and online intermediaries to optimize the design of online sponsored search markets

    Catchment Care - Developing an Auction Process for Biodiversity and Water Quality Gains. Volume 1 - Report

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    This report describes the design, development and trial of catchment care. Catchment Care is an auction-based system which aims to increase the cost effectiveness of funds for private on-ground natural resource management actions.Water;Australia;Natural Resource Management;Catchment Care; auction.

    Theoretical Development of Creative Thinking: The Role of Integrative Thinking and Social Cognition

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    Creative thinking is the psychological mechanism underlying the descriptive process that produces real-life creative outcomes. However, the connection between individual creative thinking and real-life creativity remains unclear. For example, the widely employed psychometric tools for creative thinking showed limited predictive power towards real-life creativity. In addition, empirical evidence for the social psychology of creativity is inconsistent. Also, the links between creative thinking and social cognitive process are rarely validated in the field. Besides, some domains that require creativity lack guiding theories and empirical evidence. Therefore, this research project aimed to advance the understanding of creative thinking and its role in real-life situations. To address the knowledge gap and fulfil the central purpose, we conducted four pilot and seven main studies using quantitative research methods. Accordingly, we created an integrative-thinking-based psychometric tool - Function Synthesis Task and validated its discriminate validity and predictive ability towards engineering students' creative product design. To understand the link between social comparison and creativity, we produced a new experimental paradigm that addressed existing methodological issues. We employed the paradigm and found that competition and star rating feedback altered speed or performance in creative thinking tasks. Besides, we produced a new product design task based on a hot topic at the time and found that ranking feedback benefited engineering students' creative performance in the task. Moreover, we designed a new un-stereotype intervention and found its effectiveness in improving marketers' divergent thinking. We also found that advertising stereotypes increased audiences' perceived creativity. Our research shows that integrative thinking and social cognition might play essential roles in developing the theory of creative thinking and offers novel research tools for future studies. We also form practical advice to guide educators, organisational leaders, and policymakers to promote creativity, diversity, and inclusion in real-life situations

    Essays on Service Operations Management

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    This dissertation studies three different problems service firms can face. The first chapter looks at the optimal way to price reservations and services when customers make reservations in advance, while they are uncertain about the future value of service, to avoid waiting on the day of service. We show that charging customers the full price as non-refundable deposit when they make reservations and charging zero for service when they show up to claim their reservations is optimal for the firm. When the firm faces very large potential market, then it is better for the firm to not take reservations and accept only walk-ins. The second chapter looks at a problem of how to mitigate worker demotivations due to fairness concerns, when workers have intrinsic difference in quality, and higher quality server tends to be overcrowded by customers willing to receive higher quality service. We suggest distributing workload fairly between workers and compensating workers per workload as potential remedies and show which remedy works well under what operational conditions. We show that compensating workers per customer they serve results in high customer expected utility and expected quality. However, when customers also care about fairness and dislike receiving inferior service compared to other customers, then there does not exist a single remedy that results in both high customer expected utilization and high expected quality. In the third chapter, we study how a service firm should choose its advertising strategy when the service quality is not perfectly known to the customers. We model customers\u27 learning process using a Markov chain, and show that when customers do not perfectly learn the quality of service from advertisements, then the firm is better off by advertising actively when customers\u27 initial belief about service quality is low. Oppositely, when customers initially believe the service quality to be high, then it is better for the firm to stay silent and not use advertisement to signal its quality. In all three chapters, we use game theory to model the interactions among the participants of the problem and find the equilibrium outcomes

    Online Advertising Assignment Problems Considering Realistic Constraints

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    ํ•™์œ„๋…ผ๋ฌธ (๋ฐ•์‚ฌ) -- ์„œ์šธ๋Œ€ํ•™๊ต ๋Œ€ํ•™์› : ๊ณต๊ณผ๋Œ€ํ•™ ์‚ฐ์—…๊ณตํ•™๊ณผ, 2020. 8. ๋ฌธ์ผ๊ฒฝ.With a drastic increase in online communities, many companies have been paying attention to online advertising. The main advantages of online advertising are traceability, cost-effectiveness, reachability, and interactivity. The benefits facilitate the continuous popularity of online advertising. For Internet-based companies, a well-constructed online advertisement assignment increases their revenue. Hence, the managers need to develop their decision-making processes for assigning online advertisements on their website so that their revenue is maximized. In this dissertation, we consider online advertising assignment problems considering realistic constraints. There are three types of online advertising assignment problems: (i) Display ads problem in adversarial order, (ii) Display ads problem in probabilistic order, and (iii) Online banner advertisement scheduling for advertising effectiveness. Unlike previous assignment problems, the problems are pragmatic approaches that reflect realistic constraints and advertising effectiveness. Moreover, the algorithms the dissertation designs offer important insights into the online advertisement assignment problem. We give a brief explanation of the fundamental methodologies to solve the online advertising assignment problems in Chapter 1. At the end of this chapter, the contributions and outline of the dissertation are also presented. In Chapter 2, we propose the display ads problem in adversarial order. Deterministic algorithms with worst-case guarantees are designed, and the competitive ratios of them are presented. Upper bounds for the problem are also proved. We investigate the display ads problem in probabilistic order in Chapter 3. This chapter presents stochastic online algorithms with scenario-based stochastic programming and Benders decomposition for two probabilistic order models. In Chapter 4, an online banner advertisement scheduling model for advertising effectiveness is designed. We also present the solution methodologies used to obtain valid lower and upper bounds of the model efficiently. Chapter 5 offers conclusions and suggestion for future studies. The approaches to solving the problems are meaningful in both academic and industrial areas. We validate these approaches can solve the problems efficiently and effectively by conducting computational experiments. The models and solution methodologies are expected to be convenient and beneficial when managers at Internet-based companies place online advertisements on their websites.์˜จ๋ผ์ธ ์ปค๋ฎค๋‹ˆํ‹ฐ์˜ ๊ธ‰๊ฒฉํ•œ ์„ฑ์žฅ์— ๋”ฐ๋ผ, ๋งŽ์€ ํšŒ์‚ฌ๋“ค์ด ์˜จ๋ผ์ธ ๊ด‘๊ณ ์— ๊ด€์‹ฌ์„ ๊ธฐ์šธ์ด๊ณ  ์žˆ๋‹ค. ์˜จ๋ผ์ธ ๊ด‘๊ณ ์˜ ์žฅ์ ์œผ๋กœ๋Š” ์ถ”์  ๊ฐ€๋Šฅ์„ฑ, ๋น„์šฉ ํšจ๊ณผ์„ฑ, ๋„๋‹ฌ ๊ฐ€๋Šฅ์„ฑ, ์ƒํ˜ธ์ž‘์šฉ์„ฑ ๋“ฑ์ด ์žˆ๋‹ค. ์˜จ๋ผ์ธ์— ๊ธฐ๋ฐ˜์„ ๋‘๋Š” ํšŒ์‚ฌ๋“ค์€ ์ž˜ ์งœ์—ฌ์ง„ ์˜จ๋ผ์ธ ๊ด‘๊ณ  ํ• ๋‹น๊ฒฐ์ •์— ๊ด€์‹ฌ์„ ๋‘๊ณ  ์žˆ๊ณ , ์ด๋Š” ๊ด‘๊ณ  ์ˆ˜์ต๊ณผ ์—ฐ๊ด€๋  ์ˆ˜ ์žˆ๋‹ค. ๋”ฐ๋ผ์„œ ์˜จ๋ผ์ธ ๊ด‘๊ณ  ๊ด€๋ฆฌ์ž๋Š” ์ˆ˜์ต์„ ๊ทน๋Œ€ํ™” ํ•  ์ˆ˜ ์žˆ๋Š” ์˜จ๋ผ์ธ ๊ด‘๊ณ  ํ• ๋‹น ์˜์‚ฌ ๊ฒฐ์ • ํ”„๋กœ์„ธ์Šค๋ฅผ ๊ฐœ๋ฐœํ•˜์—ฌ์•ผ ํ•œ๋‹ค. ๋ณธ ๋…ผ๋ฌธ์—์„œ๋Š” ํ˜„์‹ค์ ์ธ ์ œ์•ฝ์„ ๊ณ ๋ คํ•œ ์˜จ๋ผ์ธ ๊ด‘๊ณ  ํ• ๋‹น ๋ฌธ์ œ๋“ค์„ ์ œ์•ˆํ•œ๋‹ค. ๋ณธ ๋…ผ๋ฌธ์—์„œ ๋‹ค๋ฃจ๋Š” ๋ฌธ์ œ๋Š” (1) adversarial ์ˆœ์„œ๋กœ ์ง„ํ–‰ํ•˜๋Š” ๋””์Šคํ”Œ๋ ˆ์ด ์• ๋“œ๋ฌธ์ œ, (2) probabilistic ์ˆœ์„œ๋กœ ์ง„ํ–‰ํ•˜๋Š” ๋””์Šคํ”Œ๋ ˆ์ด ์• ๋“œ๋ฌธ์ œ ๊ทธ๋ฆฌ๊ณ  (3) ๊ด‘๊ณ ํšจ๊ณผ๋ฅผ ์œ„ํ•œ ์˜จ๋ผ์ธ ๋ฐฐ๋„ˆ ๊ด‘๊ณ  ์ผ์ •๊ณ„ํš์ด๋‹ค. ์ด์ „์— ์ œ์•ˆ๋˜์—ˆ๋˜ ๊ด‘๊ณ  ํ• ๋‹น ๋ฌธ์ œ๋“ค๊ณผ ๋‹ฌ๋ฆฌ, ๋ณธ ๋…ผ๋ฌธ์—์„œ ์ œ์•ˆํ•œ ๋ฌธ์ œ๋“ค์€ ํ˜„์‹ค์ ์ธ ์ œ์•ฝ๊ณผ ๊ด‘๊ณ ํšจ๊ณผ๋ฅผ ๋ฐ˜์˜ํ•˜๋Š” ์‹ค์šฉ์ ์ธ ์ ‘๊ทผ ๋ฐฉ์‹์ด๋‹ค. ๋˜ํ•œ ์ œ์•ˆํ•˜๋Š” ์•Œ๊ณ ๋ฆฌ์ฆ˜์€ ์˜จ๋ผ์ธ ๊ด‘๊ณ  ํ• ๋‹น ๋ฌธ์ œ์˜ ์šด์˜๊ด€๋ฆฌ์— ๋Œ€ํ•œ ํ†ต์ฐฐ๋ ฅ์„ ์ œ๊ณตํ•œ๋‹ค. 1์žฅ์—์„œ๋Š” ์˜จ๋ผ์ธ ๊ด‘๊ณ  ํ• ๋‹น ๋ฌธ์ œ์— ๋Œ€ํ•œ ๋ฌธ์ œํ•ด๊ฒฐ ๋ฐฉ๋ฒ•๋ก ์— ๋Œ€ํ•ด ๊ฐ„๋‹จํžˆ ์†Œ๊ฐœํ•œ๋‹ค. ๋”๋ถˆ์–ด ์—ฐ๊ตฌ์˜ ๊ธฐ์—ฌ์™€ ๊ฐœ์š”๋„ ์ œ๊ณต๋œ๋‹ค. 2์žฅ์—์„œ๋Š” adversarial ์ˆœ์„œ๋กœ ์ง„ํ–‰ํ•˜๋Š” ๋””์Šคํ”Œ๋ ˆ์ด ์• ๋“œ๋ฌธ์ œ๋ฅผ ์ œ์•ˆํ•œ๋‹ค. worst-case๋ฅผ ๋ณด์žฅํ•˜๋Š” ๊ฒฐ์ •๋ก ์  ์•Œ๊ณ ๋ฆฌ์ฆ˜์„ ์„ค๊ณ„ํ•˜๊ณ , ์ด๋“ค์˜ competitive ratio๋ฅผ ์ฆ๋ช…ํ•œ๋‹ค. ๋”๋ถˆ์–ด ๋ฌธ์ œ์˜ ์ƒํ•œ๋„ ์ž…์ฆ๋œ๋‹ค. 3์žฅ์—์„œ๋Š” probabilistic ์ˆœ์„œ๋กœ ์ง„ํ–‰ํ•˜๋Š” ๋””์Šคํ”Œ๋ ˆ์ด ์• ๋“œ๋ฌธ์ œ๋ฅผ ์ œ์•ˆํ•œ๋‹ค. ์‹œ๋‚˜๋ฆฌ์˜ค ๊ธฐ๋ฐ˜์˜ ํ™•๋ฅ ๋ก ์  ์˜จ๋ผ์ธ ์•Œ๊ณ ๋ฆฌ์ฆ˜๊ณผ Benders ๋ถ„ํ•ด๋ฐฉ๋ฒ•์„ ํ˜ผํ•ฉํ•œ ์ถ”๊ณ„ ์˜จ๋ผ์ธ ์•Œ๊ณ ๋ฆฌ์ฆ˜์„ ์ œ์‹œํ•œ๋‹ค. 4์žฅ์—์„œ๋Š” ๊ด‘๊ณ ํšจ๊ณผ๋ฅผ ์œ„ํ•œ ์˜จ๋ผ์ธ ๋ฐฐ๋„ˆ ๊ด‘๊ณ  ์ผ์ •๊ณ„ํš์„ ์„ค๊ณ„ํ•œ๋‹ค. ๋˜ํ•œ, ๋ชจ๋ธ์˜ ์œ ํšจํ•œ ์ƒํ•œ๊ณผ ํ•˜ํ•œ์„ ํšจ์œจ์ ์œผ๋กœ ์–ป๋Š” ๋ฐ ์‚ฌ์šฉ๋˜๋Š” ๋ฌธ์ œํ•ด๊ฒฐ ๋ฐฉ๋ฒ•๋ก ์„ ์ œ์•ˆํ•œ๋‹ค. 5์žฅ์—์„œ๋Š” ๋ณธ ๋…ผ๋ฌธ์˜ ๊ฒฐ๋ก ๊ณผ ํ–ฅํ›„ ์—ฐ๊ตฌ๋ฅผ ์œ„ํ•œ ๋ฐฉํ–ฅ์„ ์ œ๊ณตํ•œ๋‹ค. ๋ณธ ๋…ผ๋ฌธ์—์„œ ์ œ์•ˆํ•˜๋Š” ๋ฌธ์ œํ•ด๊ฒฐ ๋ฐฉ๋ฒ•๋ก ์€ ํ•™์ˆ  ๋ฐ ์‚ฐ์—… ๋ถ„์•ผ ๋ชจ๋‘ ์˜๋ฏธ๊ฐ€ ์žˆ๋‹ค. ์ˆ˜์น˜ ์‹คํ—˜์„ ํ†ตํ•ด ๋ฌธ์ œํ•ด๊ฒฐ ์ ‘๊ทผ ๋ฐฉ์‹์ด ๋ฌธ์ œ๋ฅผ ํšจ์œจ์ ์ด๊ณ  ํšจ๊ณผ์ ์œผ๋กœ ํ•ด๊ฒฐํ•  ์ˆ˜ ์žˆ์Œ์„ ๋ณด์ธ๋‹ค. ์ด๋Š” ์˜จ๋ผ์ธ ๊ด‘๊ณ  ๊ด€๋ฆฌ์ž๊ฐ€ ๋ณธ ๋…ผ๋ฌธ์—์„œ ์ œ์•ˆํ•˜๋Š” ๋ฌธ์ œ์™€ ๋ฌธ์ œํ•ด๊ฒฐ ๋ฐฉ๋ฒ•๋ก ์„ ํ†ตํ•ด ์˜จ๋ผ์ธ ๊ด‘๊ณ  ํ• ๋‹น๊ด€๋ จ ์˜์‚ฌ๊ฒฐ์ •์„ ์ง„ํ–‰ํ•˜๋Š” ๋ฐ ์žˆ์–ด ๋„์›€์ด ๋  ๊ฒƒ์œผ๋กœ ๊ธฐ๋Œ€ํ•œ๋‹ค.Chapter 1 Introduction 1 1.1 Display Ads Problem 3 1.1.1 Online Algorithm 4 1.2 Online Banner Advertisement Scheduling Problem 5 1.3 Research Motivations and Contributions 6 1.4 Outline of the Dissertation 9 Chapter 2 Online Advertising Assignment Problem in Adversarial Order 12 2.1 Problem Description and Literature Review 12 2.2 Display Ads Problem in Adversarial Order 15 2.3 Deterministic Algorithms for Adversarial Order 17 2.4 Upper Bounds of Deterministic Algorithms for Adversarial Order 22 2.5 Summary 28 Chapter 3 Online Advertising Assignment Problem in Probabilistic Order 30 3.1 Problem Description and Literature Review 30 3.2 Display Ads Problem in Probabilistic Order 33 3.3 Stochastic Online Algorithms for Probabilistic Order 34 3.3.1 Two-Stage Stochastic Programming 35 3.3.2 Known IID model 37 3.3.3 Random permutation model 41 3.3.4 Stochastic approach using primal-dual algorithm 45 3.4 Computational Experiments 48 3.4.1 Results for known IID model 55 3.4.2 Results for random permutation model 57 3.4.3 Managerial insights for Algorithm 3.1 59 3.5 Summary 60 Chapter 4 Online Banner Advertisement Scheduling for Advertising Effectiveness 61 4.1 Problem Description and Literature Review 61 4.2 Mathematical Model 68 4.2.1 Objective function 68 4.2.2 Notations and formulation 72 4.3 Solution Methodologies 74 4.3.1 Heuristic approach to finding valid lower and upper bounds 75 4.3.2 Hybrid tabu search 79 4.4 Computational Experiments 80 4.4.1 Results for problems with small data sets 82 4.4.2 Results for problems with large data sets 84 4.4.3 Results for problems with standard data 86 4.4.4 Managerial insights for the results 90 4.5 Summary 92 Chapter 5 Conclusions and Future Research 93 Appendices 97 A Initial Sequence of the Hybrid Tabu Search 98 B Procedure of the Hybrid Tabu Search 99 C Small Example of the Hybrid Tabu Search 101 D Linearization Technique of Bilinear Form in R2 104 Bibliography 106Docto

    Keyword Targeting Optimization in Sponsored Search Advertising: Combining Selection and Matching

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    In sponsored search advertising (SSA), advertisers need to select keywords and determine matching types for selected keywords simultaneously, i.e., keyword targeting. An optimal keyword targeting strategy guarantees reaching the right population effectively. This paper aims to address the keyword targeting problem, which is a challenging task because of the incomplete information of historical advertising performance indices and the high uncertainty in SSA environments. First, we construct a data distribution estimation model and apply a Markov Chain Monte Carlo method to make inference about unobserved indices (i.e., impression and click-through rate) over three keyword matching types (i.e., broad, phrase and exact). Second, we formulate a stochastic keyword targeting model (BB-KSM) combining operations of keyword selection and keyword matching to maximize the expected profit under the chance constraint of the budget, and develop a branch-and-bound algorithm incorporating a stochastic simulation process for our keyword targeting model. Finally, based on a realworld dataset collected from field reports and logs of past SSA campaigns, computational experiments are conducted to evaluate the performance of our keyword targeting strategy. Experimental results show that, (a) BB-KSM outperforms seven baselines in terms of profit; (b) BB-KSM shows its superiority as the budget increases, especially in situations with more keywords and keyword combinations; (c) the proposed data distribution estimation approach can effectively address the problem of incomplete performance indices over the three matching types and in turn significantly promotes the performance of keyword targeting decisions. This research makes important contributions to the SSA literature and the results offer critical insights into keyword management for SSA advertisers.Comment: 38 pages, 4 figures, 5 table
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