基于歧视性的第二价格拍卖算法的激励机制

在基于对等网(P2P)的大数据实时应用中,针对如何遏制视频点播(VOD)系统中的节点搭便车行为,提出了基于歧视性的第二价格拍卖算法的激励机制。节点之间以分布式动态拍卖的方式获取各自所需视频数据块,拍卖中,拍卖节点首先根据歧视性原则判断竞标节点的预算是否足以参与竞标,并根据允许参与竞标的节点数目设置上传带宽;然后根据竞标节点的出价确定赢得竞标的节点;最后竞标节点在接收到数据块后根据第二价格方案支付拍卖节点仅次于拍卖最高价格的第二高价格的要价作为节点的收益。分析节点的收益、节点带宽的利用率以及贡献节点/自私节点的比例,表明该方案能有效地激励节点积极地参与视频数据块的共享,同时高效地利用节点的上传带宽。     

基于模糊博弈的英式拍卖动态模型

为了给竞价人或其代理的竞价提供决策支持,提出了模糊博弈的英式拍卖动态模型.以模糊参数出价意愿取代估价作为分析的基础,采用Bellman和Zadeh的模糊决策理论替代博弈论中的Nash平衡理论,分析英式拍卖中的竞价行为,建立英式拍卖静态博弈均衡模型,进而提出动态博弈模型和分析动态拍卖策略.通过仿真实验证明算法的有效性.     

基于组合拍卖机制的移动Agent投标策略

针对Agent系统资源分配需求提出一种兼顾Agent时间片数量要求和执行截止期限要求的投标策略。定义CPU时间片组合拍卖问题模型,设计Agent各种投标信息处理方法,包括适合组合拍卖CPU时间片机制的Agent零智能投标算法和NZIPca投标算法。仿真结果表明NZIPca策略具有较强的竞标能力。     

基于分解的多目标多因子进化算法

多目标多因子优化(MO-MFO)问题作为一类新的优化问题近年来受到了众多关注,其特点是需要利用单个种群来同时优化多个多目标优化任务.针对该问题,提出一个基于分解策略的多目标多因子进化算法(MFEA/D).算法通过多组权重向量,将MO-MFO问题中的每个任务分解成一系列单目标优化子问题,并用单个种群同时优化.在种群进化过程中提出不同任务之间的信息交流策略,以充分挖掘不同任务之间的有用信息,进而加快每个任务的收敛速度.基于10个多目标多因子标准测试问题的实验结果表明,所提出的不同任务之间的信息交流策略能够加快问题的求解速度,使得MFEA/D算法显著优于当前的MO-MFEA算法.     

基于用户迁徙网络的广告投放策略研究

分析了目前网络广告投放领域存在的不足。使用能够体现网站间共同用户数量的用户迁徙网络作为平台,研究广告投放的网站选择策略。通过分析传统的网络广告投放问题的数学模型,发现其本质为0-1背包问题。通过实验比较,解决0-1背包问题常用的贪心算法和蚁群算法不能解决的广告受众重叠的问题;而使用用户迁徙网络的广告投放方法,在预算一定的情况下,达到广告的受众最多,广告投放的效果最优,是广告投放的最佳策略。     

基于松弛预留策略的连续双向拍卖模型

针对网格资源的松弛预留问题,提出一种改进的连续双向拍卖模型。在网格资源定价策略中,引入松弛时间保证更高的任务预留接纳率。在用户出价和要价策略中,买方通过剩余时间和剩余资源量出价,卖方根据负载情况要价。仿真实验结果表明,对于具有费用约束的网格任务,该模型能增加约21%的资源总收益,提高约15%的资源利用率。     

为网上传播提速——论网络广告的监测及结果评估

有一句广告业的名言,客户总在抱怨:我知道我的广告预算的一半被浪费了,但我不知道浪费在哪里。虽然广告不是市场传播全部的惟一途径,但毕竟广告客户的大部分预算都花费在广告预算上。因而客户对于广告的监测尤为关注,广告客户都希望知道广告做出去有多少人看了.看了多少,看后会不会产生购买需求。让我们先回过头来从传统媒体广告监测及结果评估。广告类型大体上分为两大类:品牌形象广告及促销广告。对品牌形象广告,广告主要通过传达广告塑造产品独特、鲜明的品牌特性,用传媒方式深入消费者脑海中,使消费者对某一类产品中某个品牌产生偏好。而促销广告,则着重于对某类固定目标对象群,采用降价、打包赠送礼品、做巡回展示、POP等促销方式,促使消费者产生购买需求。因而对于传统媒体,广告监测大多表现在随报纸、杂志添加     

时空众包中基于质量感知的在线激励机制

在实时、复杂的网络环境中，如何激励工人参与任务并得到高质量的感知数据是时空众包研究的重点。基于此，提出一种基于质量感知的时空众包在线激励机制。首先，为了适应时空众包实时性的特点，提出一种阶段性在线选择工人算法（POA），该算法在预算约束下将整个众包活动周期分为多个阶段，每个阶段在线选择工人；其次，为了提高质量预估的精度与效率，提出一种改进的最大期望（IEM）算法，该算法在算法迭代的过程中优先考虑可信度高的工人提交的任务结果；最后，通过真实数据集上的对比实验，验证了所提激励机制在提高平台效用方面的有效性。实验结果表明，POA相较于改进的两阶段拍卖（ITA）算法、多属性与两阶段相结合的拍卖（M-ITA）算法，以及L-VCG(Lyapunov-based Vickrey-Clarke-Groves)等拍卖算法，效率平均提高了11.11%，工人的额外奖励金额平均提升了12.12%，可以激励工人向冷门偏远地区移动；在质量预估方面，IEM算法相比其他质量预估算法，在精度和效率上分别平均提高了5.06%和14.2%。     

基于Q学习算法的X光主动视觉安检方法

针对主动视觉安检方法检测性能不高和检测速度慢的问题,基于Q学习（QL）算法提出了采用状态回溯的启发式Q学习（HASB-QL）算法进行最佳视角估计。该算法引入代价函数和启发函数,提高了学习效率,加快了Q学习收敛。首先,对通过安检扫描仪获取的X光图像进行单视角检测;然后,对姿势作出估计并通过在状态回溯过程中比较重复动作的选择策略获取最佳旋转角度,再次进行单视角检测,直到检测到危险品;此外,在检测过程中多于一个视角时,建立几何约束以消除误报。对GDXray数据集中的手枪和剃刀刀片的X光图像进行实验,实验结果表明,相比于以Q学习为基础的主动视觉算法,改进的主动视觉算法检测手枪所得精确率和召回率之间的加权平均值F₁值提高了9.60%,检测速度提高了12.45%;检测剃刀刀片所得的F₁值提高了2.51%,速度提高了17.39%。所提算法提高了危险品检测的性能和速度。     

连续双向拍卖中演化Risk-Based策略研究

Risk-Based策略是基于风险行为的代理策略。为了改善Risk-Based代理的行为,使交易价格迅速收敛于市场均衡价格,提高市场效率,提出利用粒子群优化算法演化Risk-Based策略参数。首先分析了影响Risk-Based代理行为的关键参数;之后提出了改进的粒子群优化算法演化Risk-Based策略关键参数的模型。最后,在基于市场控制的模拟系统中采用连续双向拍卖机制对演化Risk-Based策略进行了实验评价,结果表明演化后的Risk-Based策略比演化前的策略更为优秀。     

基于淘宝直通车的竞价决策系统的研究与设计

电子商务蓬勃发展的大环境下,广告主具有强烈的电商广告投放意愿,显然他们并未达到电商广告的核心业务SEM （搜索引擎营销优化）的专业要求。所以广告主希望借助第三方工具来进行搜索引擎广告投放的一站式服务来满足其业务需求。基于此,本文将提供一整套的竞价词托管式服务的解决方案。以淘宝直通车这一全新的搜索竞价模式作为研究对象,从语义抽取、关键词扩展、竞价词生成、模型化出价、广告效果正向反馈监控模型几方面进行分析和统计,为直通车广告主提供最优投放策略整体解决方案。第一阶段针对商品信息进行数据挖掘,实现关键词推荐引擎。第二阶段实现投放优化模块,实施定价策略,建立的点击量与PPC（“平均点击花费”）模型,实现在预算资金的约束下对不同竞价组合进行ROI（投入产出比）最大化的投资决策。以实际效果改善直通车竞价搜索用户体验。     

Design of online auctions: Proxy versus non-proxy settings

Recent years have witnessed the rapid development of online auctions. Currently, some online auctions, such as eBay, introduce a proxy bidding policy, under which bidders submit their maximum bids and delegate to a proxy agent to automatically outbid other competitors for the top bidder, whereas other online auctions do not. This paper compares these two widely used auction mechanisms (proxy setting and non-proxy setting) and characterizes the equilibrium bidding behavior and the seller's expected revenue. We find the proxy auction outperforms the non-proxy auction in terms of the seller's expected revenue. This dominance result is not prone to the specific bid announcement policy, the bidder's knowledge regarding the number of bidders, the impact of traffic congestion along the bidding process, the number of items sold through the auction, and the existence of a reserve price.We further find that the proxy setting usually fails to sustain the truthful bidding as a dominant strategy equilibrium even if no minimum bid increments are adopted, and the possibility of a low-valuation-bidder dilemma where the low-valuation bidders could be better off if all bidders collude to bid at the last minute. We also discuss the dramatically different equilibrium bidding behaviors under the two auction mechanisms.     

Probabilistic Automated Bidding in Multiple Auctions

This paper presents an approach to develop bidding agents that participate in multiple auctions with the goal of obtaining an item with a given probability. The approach consists of a prediction method and a planning algorithm. The prediction method exploits the history of past auctions to compute probability functions capturing the belief that a bid of a given price may win a given auction. The planning algorithm computes a price and a set of compatible auctions, such that by sequentially bidding this price in each of the auctions, the agent can obtain the item with the desired probability. Experiments show that the approach increases the payoff of their users and the welfare of the market.     

Autonomous Adaptive Agents for Single Seller Sealed Bid Auctions

In developing open, heterogeneous and distributed multi-agent systems researchers often face a problem of facilitating negotiation and bargaining amongst agents. It is increasingly common to use auction mechanisms for negotiation in multi-agent systems. The choice of auction mechanism and the bidding strategy of an agent are of central importance to the success of the agent model. Our aim is to determine the best agent learning algorithm for bidding in a variety of single seller auction structures in both static environments where a known optimal strategy exists and in complex environments where the optimal strategy may be constantly changing. In this paper we present a model of single seller auctions and describe three adaptive agent algorithms to learn strategies through repeated competition. We experiment in a range of auction environments of increasing complexity to determine how well each agent performs, in relation to an optimal strategy in cases where one can be deduced, or in relation to each other in other cases. We find that, with a uniform value distribution, a purely reactive agent based on Cliff’s ZIP algorithm for continuous double auctions (CDA) performs well, although is outperformed in some cases by a memory based agent based on the Gjerstad Dickhaut agent for CDA.     

MoCAAS: auction agent system using a collaborative mobile agent in electronic commerce

To get the items that a buyer wants in an Internet auction, he must search for the items through several auction sites. When the bidding starts, the buyer needs to connect to these auction sites frequently so that he can monitor the bid states and re-bid. A reserve-price auction reduces the number of connections, but this limits the user's bidding strategy. Another problem is equity between the buyer and the seller. Both the buyer and the seller should profit within proper limits. In this paper, we propose an auction agent system using a collaborative mobile agent and a brokering mechanism called MoCAAS (Mobile collaborative auction agent system), which mediates between the buyer and the seller and executes bidding asynchronously and autonomously. This reduces the network load more than with other auction-agents, offers more intelligent bidding, and increases the clear ratio.     

基于组合双向拍卖的云资源调度方法

针对跨数据中心的资源调度问题，提出了一种基于组合双向拍卖（PCDA）的资源调度方案。首先，将云资源拍卖分为三个部分：云用户代理报价、云资源提供商要价、拍卖代理组织拍卖；其次，在定义用户的优先级及任务紧迫度的基础上，在拍卖过程中估算每一个工作发生的服务等级协议（SLA）违规并以此计算云提供商的收益，同时每轮竞拍允许成交多项交易；最终达到根据用户等级合理分配云资源调度的效果。仿真实验结果表明该算法保证了竞拍成功率，与传统一次拍卖成交一项的组合双向拍卖方案相比，PCDA在竞拍时间段产生的能耗降低了35.00%，拍卖云提供商的利润提高了约38.84%。     

Repeated Budgeted Second Price Ad Auction

Our main goal is to abstract existing repeated sponsored search ad auction mechanisms which incorporate budgets, and study their equilibrium and dynamics. Our abstraction has multiple agents bidding repeatedly for multiple identical items (such as impressions in an ad auction). The agents are budget limited and have a value per item. We abstract this repeated interaction as a one-shot game, which we call budget auction, where agents submit a bid and a budget, and then items are sold by a sequential second price auction. Once an agent exhausts its budget it does not participate in the proceeding auctions. Our main result shows that if agents bid conservatively (never bid above their value) then there always exists a pure Nash equilibrium. We also study simple dynamics of repeated budget auctions, showing their convergence to a Nash equilibrium for two agents and for multiple agents with identical budgets.     

What Format for Multi-Unit Multiple-Bid Auctions?

This paper uses computational experiments where bidders learn over nonlinear bidding strategies to compare outcomes for alternative pricing format for multi-unit multiple-bid auctions. Multi-unit multiple-bid auctions, in which bidders are allowed to submit multiple price-quantity bids, are promising mechanisms for the allocation of a range of resources. The main advantage of such auctions is to avoid the lumpy bid problem which arises when bidders can only compete on the basis of one bid. However, there is great uncertainty about the best auction formats when multi-unit auctions are used. The theory can only supply the expected structural properties of equilibrium strategies and the multiplicity of potential equilibria makes comparisons across auction formats difficult. Empirical studies and experiments have improved our knowledge of multi-unit auctions but they remain scarce and most experiments are restricted to two bidders and two units. Moreover, they demonstrate that bidders have limited rationality and learn through experience. This paper constructs an agent-based computational model of bidders to compare the performance of alternative procurement auction formats under circumstances where bidders submit continuous bid supply functions and learn over time to adjust their bids in order to improve their net incomes. The setting is for independent private values. We show that bidding behaviour displays more interesting patterns than is depicted in the theoretical literature and that bidding patterns depend on the interplay between heterogeneity in the bidder population and the degree of rationing in the auction. Results indicate that the three auction formats have similar performance for most levels of competition but that their performances differ when competition is weak. This ranking is dependent on whether the population of bidders is homogenous or heterogeneous.