Purpose: This study attempts to investigate how a user's search behavior changes in the exploratory search process in order to understand the characteristics of the user's search behavior and build a behaviora...Purpose: This study attempts to investigate how a user's search behavior changes in the exploratory search process in order to understand the characteristics of the user's search behavior and build a behavioral model.Design/methodology/approach: Forty-two matriculated full-time senior college students with a female-to-male ratio of 1 to 1 who majored in medical science in Jilin University participated in our experiment. The task of the experiment was to search for information about 'the influence of environmental pollution on daily life' in order to write a report about this topic. The research methods include concept map, query log analysis and questionnaire survey.Findings: The results indicate that exploratory search can significantly change the knowledge structure of searchers. As searchers were moving through different stages of the exploratory search process, they experienced cognitive changes, and their search behaviors were characterized by quick browsing, careful browsing and focused searching.Research limitations: The study used only one search topic, and there is no comparision or control group. Although we took search habits, personal thinking habits, personality characteristics and professional background into account, a more detailed study to analyze the effects of these factors on exploratory search behavior is needed in our further research.Practical implications: This study can serve as a reference for other researchers engaged in the same effort to construct the supporting system of exploratory search.Originality/value: Three methods are used to investigate the behavior characteristics during exploratory search.展开更多
The existing search engines are lack of the consideration of personalization and display the same search results for different users despite their differences in interesting and purpose. By analyzing user's dynamic s...The existing search engines are lack of the consideration of personalization and display the same search results for different users despite their differences in interesting and purpose. By analyzing user's dynamic search behavior, the paper introduces a new method of using a keyword query graph to express user's dynamic search behavior, and uses Bayesian network to construct the prior probability of keyword selection and the migration probability between keywords for each user. To reflect the dynamic changes of the user's preference, the paper introduces non-lineal gradual forgetting collaborative filtering strategy into the personalized search recommendation model. By calculating the similarity between each two users, the model can do the recommendation based on neighbors and be used to construct the personalized search engine.展开更多
Purpose: This study aims to explore the relationships between different facets of work task and selection and query-related behavior.Design/methodology/approach:An experiment was conducted to explore the issue. The re...Purpose: This study aims to explore the relationships between different facets of work task and selection and query-related behavior.Design/methodology/approach:An experiment was conducted to explore the issue. The researcher recruited 24 participants and assigned six simulated work task situations to each of them. Each experiment lasted around 2 hours and was recorded by the software tool Morae.Findings: Time(frequency) and time(length) are more closely related to user’s selection and query-related behavior compared to the facet ‘process’ of work task. Knowledge level of work task topic, degree of work task difficulty, and subjective work task complexity are significantly correlated with selection and query-related behavior. Work task difficulty and work task complexity are different concepts. Subjective work task complexity, work task difficulty, and knowledge of work task topic are significantly correlated with user’s selection and query-related behavior.Research limitations/implications: The limitations of this study include a small sample size,limited work task situations, and possible spurious relationships. This study has implications in informing task-based information seeking/search/retrieval research and interactive information retrieval(IIR) systems design.Originality/values: Previous studies usually did not touch upon how different facets of work tasks affected interactive activities. Some studies examining task complexity and information behavior were concerned with how work tasks affect users’ behavior at information-seeking level, rather than at information search level. This study makes contribution to interactive information retrieval,task-based information search and retrieval, and personalization of IR.展开更多
A novel heuristic search algorithm called seeker op- timization algorithm (SOA) is proposed for the real-parameter optimization. The proposed SOA is based on simulating the act of human searching. In the SOA, search...A novel heuristic search algorithm called seeker op- timization algorithm (SOA) is proposed for the real-parameter optimization. The proposed SOA is based on simulating the act of human searching. In the SOA, search direction is based on empir- ical gradients by evaluating the response to the position changes, while step length is based on uncertainty reasoning by using a simple fuzzy rule. The effectiveness of the SOA is evaluated by using a challenging set of typically complex functions in compari- son to differential evolution (DE) and three modified particle swarm optimization (PSO) algorithms. The simulation results show that the performance of the SOA is superior or comparable to that of the other algorithms.展开更多
点阵材料具有轻质、抗冲击、高能量吸收等特性,因而在航天飞行器承载部件设计等领域有广阔应用前景.通过对点阵材料内部杆径进行合理的梯度设计,可以提高点阵材料在高速冲击载荷作用下的动态力学性能.利用仿真模拟数据,基于随机森林模...点阵材料具有轻质、抗冲击、高能量吸收等特性,因而在航天飞行器承载部件设计等领域有广阔应用前景.通过对点阵材料内部杆径进行合理的梯度设计,可以提高点阵材料在高速冲击载荷作用下的动态力学性能.利用仿真模拟数据,基于随机森林模型实现了梯度点阵材料的动态力学响应预测和结构参数优化.以面心立方(face center cubic,FCC)结构梯度点阵材料为研究对象,通过对杆径参数的调整实现点阵材料密度的梯度化设计.通过LS-DYNA软件计算了密度分布不同的梯度点阵材料受到冲击载荷作用时的动态力学响应,包括冲击端面与支撑端面接触应力随时间的变化曲线.基于随机森林模型,以各层胞元的相对密度为输入,实现对点阵材料端面峰值应力的预测,并基于Gini指数分析出对不同端面处峰值应力影响最大的胞元层.将网格搜索算法与训练好的随机森林对接,分别以两个端面上的峰值应力最高作为优化目标,获得点阵材料各层胞元相对密度的最优值.模型对梯度点阵材料端面峰值应力的预测误差在5%以内.数值模拟验证结果表明,优化后所得梯度点阵材料相应端面上的峰值应力高于仿真数据集内任何结构.展开更多
This study examined users' querying behaviors based on a sample of 30 Chinese college students from Peking University. The authors designed 5 search tasks and each participant conducted two randomly selected searc...This study examined users' querying behaviors based on a sample of 30 Chinese college students from Peking University. The authors designed 5 search tasks and each participant conducted two randomly selected search tasks during the experiment. The results show that when searching for pre-designed search tasks, users often have relatively clear goals and strategies before searching. When formulating their queries, users often select words from tasks, use concrete concepts directly, or extract 'central words' or keywords. When reformulating queries, seven query reformulation types were identified from users' behaviors, i.e. broadening, narrowing, issuing new query, paralleling, changing search tools, reformulating syntax terms, and clicking on suggested queries. The results reveal that the search results and/or the contexts can also influence users' querying behaviors.展开更多
白鲨优化算法是受白鲨捕猎行为的启发设计的一种新元启发式算法。该算法在求解高维优化问题时,易进入早熟状态,寻优结果精度较低。为此,文章提出一种改进的白鲨优化(improved white shake optimizer,IWSO)算法。首先使用Sinusoidal混沌...白鲨优化算法是受白鲨捕猎行为的启发设计的一种新元启发式算法。该算法在求解高维优化问题时,易进入早熟状态,寻优结果精度较低。为此,文章提出一种改进的白鲨优化(improved white shake optimizer,IWSO)算法。首先使用Sinusoidal混沌映射初始化种群,以提高种群多样性及初始解在解空间的分布性;其次,引入鸟群搜索行为,赋予白鲨游动速度自适应动态惯性权重,以提高算法的收敛速度;最后,在位置更新阶段引入精英白鲨余弦变异策略,利用余弦函数的周期性特征,驱使白鲨个体在精英白鲨的有限邻域内进行精细化开发,以提高收敛精度。在23个著名基准函数和CEC2014函数上做了性能对比实验,其结果表明,IWSO算法优于6种对比算法,适合求解函数优化问题。展开更多
Unlike consumers in the mall or supermarkets, online consumers are “intangible” and their purchasing behaviors are affected by multiple factors, including product pricing, promotion and discounts, quality of product...Unlike consumers in the mall or supermarkets, online consumers are “intangible” and their purchasing behaviors are affected by multiple factors, including product pricing, promotion and discounts, quality of products and brands, and the platforms where they search for the product. In this research, I study the relationship between product sales and consumer characteristics, the relationship between product sales and product qualities, demand curve analysis, and the search friction effect for different platforms. I utilized data from a randomized field experiment involving more than 400 thousand customers and 30 thousand products on JD.com, one of the world’s largest online retailing platforms. There are two focuses of the research: 1) how different consumer characteristics affect sales;2) how to set price and possible search friction for different channels. I find that JD plus membership, education level and age have no significant relationship with product sales, and higher user level leads to higher sales. Sales are highly skewed, with very high numbers of products sold making up only a small percentage of the total. Consumers living in more industrialized cities have more purchasing power. Women and singles lead to higher spending. Also, the better the product performs, the more it sells. Moderate pricing can increase product sales. Based on the research results of search volume in different channels, it is suggested that it is better to focus on app sales. By knowing the results, producers can adjust target consumers for different products and do target advertisements in order to maximize the sales. Also, an appropriate price for a product is also crucial to a seller. By the way, knowing the search friction of different channels can help producers to rearrange platform layout so that search friction can be reduced and more potential deals may be made.展开更多
基金supported by the National Social Science Foundation(Grant No.:11BTQ045)
文摘Purpose: This study attempts to investigate how a user's search behavior changes in the exploratory search process in order to understand the characteristics of the user's search behavior and build a behavioral model.Design/methodology/approach: Forty-two matriculated full-time senior college students with a female-to-male ratio of 1 to 1 who majored in medical science in Jilin University participated in our experiment. The task of the experiment was to search for information about 'the influence of environmental pollution on daily life' in order to write a report about this topic. The research methods include concept map, query log analysis and questionnaire survey.Findings: The results indicate that exploratory search can significantly change the knowledge structure of searchers. As searchers were moving through different stages of the exploratory search process, they experienced cognitive changes, and their search behaviors were characterized by quick browsing, careful browsing and focused searching.Research limitations: The study used only one search topic, and there is no comparision or control group. Although we took search habits, personal thinking habits, personality characteristics and professional background into account, a more detailed study to analyze the effects of these factors on exploratory search behavior is needed in our further research.Practical implications: This study can serve as a reference for other researchers engaged in the same effort to construct the supporting system of exploratory search.Originality/value: Three methods are used to investigate the behavior characteristics during exploratory search.
基金supported by the National Natural Science Foundation of China (60432010)the National Basic Research Program of China (2007CB307103)+1 种基金the Fundamental Research Funds for the Central Universities (2009RC0507)Important Science & Technology Specific Project of Guizhou Province (【2007】6017)
文摘The existing search engines are lack of the consideration of personalization and display the same search results for different users despite their differences in interesting and purpose. By analyzing user's dynamic search behavior, the paper introduces a new method of using a keyword query graph to express user's dynamic search behavior, and uses Bayesian network to construct the prior probability of keyword selection and the migration probability between keywords for each user. To reflect the dynamic changes of the user's preference, the paper introduces non-lineal gradual forgetting collaborative filtering strategy into the personalized search recommendation model. By calculating the similarity between each two users, the model can do the recommendation based on neighbors and be used to construct the personalized search engine.
基金sponsored by National Social Science Foundation of China(Grant No. 11BTQ009)
文摘Purpose: This study aims to explore the relationships between different facets of work task and selection and query-related behavior.Design/methodology/approach:An experiment was conducted to explore the issue. The researcher recruited 24 participants and assigned six simulated work task situations to each of them. Each experiment lasted around 2 hours and was recorded by the software tool Morae.Findings: Time(frequency) and time(length) are more closely related to user’s selection and query-related behavior compared to the facet ‘process’ of work task. Knowledge level of work task topic, degree of work task difficulty, and subjective work task complexity are significantly correlated with selection and query-related behavior. Work task difficulty and work task complexity are different concepts. Subjective work task complexity, work task difficulty, and knowledge of work task topic are significantly correlated with user’s selection and query-related behavior.Research limitations/implications: The limitations of this study include a small sample size,limited work task situations, and possible spurious relationships. This study has implications in informing task-based information seeking/search/retrieval research and interactive information retrieval(IIR) systems design.Originality/values: Previous studies usually did not touch upon how different facets of work tasks affected interactive activities. Some studies examining task complexity and information behavior were concerned with how work tasks affect users’ behavior at information-seeking level, rather than at information search level. This study makes contribution to interactive information retrieval,task-based information search and retrieval, and personalization of IR.
基金supported by the National Natural Science Foundation of China(60870004)
文摘A novel heuristic search algorithm called seeker op- timization algorithm (SOA) is proposed for the real-parameter optimization. The proposed SOA is based on simulating the act of human searching. In the SOA, search direction is based on empir- ical gradients by evaluating the response to the position changes, while step length is based on uncertainty reasoning by using a simple fuzzy rule. The effectiveness of the SOA is evaluated by using a challenging set of typically complex functions in compari- son to differential evolution (DE) and three modified particle swarm optimization (PSO) algorithms. The simulation results show that the performance of the SOA is superior or comparable to that of the other algorithms.
文摘点阵材料具有轻质、抗冲击、高能量吸收等特性,因而在航天飞行器承载部件设计等领域有广阔应用前景.通过对点阵材料内部杆径进行合理的梯度设计,可以提高点阵材料在高速冲击载荷作用下的动态力学性能.利用仿真模拟数据,基于随机森林模型实现了梯度点阵材料的动态力学响应预测和结构参数优化.以面心立方(face center cubic,FCC)结构梯度点阵材料为研究对象,通过对杆径参数的调整实现点阵材料密度的梯度化设计.通过LS-DYNA软件计算了密度分布不同的梯度点阵材料受到冲击载荷作用时的动态力学响应,包括冲击端面与支撑端面接触应力随时间的变化曲线.基于随机森林模型,以各层胞元的相对密度为输入,实现对点阵材料端面峰值应力的预测,并基于Gini指数分析出对不同端面处峰值应力影响最大的胞元层.将网格搜索算法与训练好的随机森林对接,分别以两个端面上的峰值应力最高作为优化目标,获得点阵材料各层胞元相对密度的最优值.模型对梯度点阵材料端面峰值应力的预测误差在5%以内.数值模拟验证结果表明,优化后所得梯度点阵材料相应端面上的峰值应力高于仿真数据集内任何结构.
基金partially supported by China Scholarship Council(Grant No.:2009601175)
文摘This study examined users' querying behaviors based on a sample of 30 Chinese college students from Peking University. The authors designed 5 search tasks and each participant conducted two randomly selected search tasks during the experiment. The results show that when searching for pre-designed search tasks, users often have relatively clear goals and strategies before searching. When formulating their queries, users often select words from tasks, use concrete concepts directly, or extract 'central words' or keywords. When reformulating queries, seven query reformulation types were identified from users' behaviors, i.e. broadening, narrowing, issuing new query, paralleling, changing search tools, reformulating syntax terms, and clicking on suggested queries. The results reveal that the search results and/or the contexts can also influence users' querying behaviors.
文摘白鲨优化算法是受白鲨捕猎行为的启发设计的一种新元启发式算法。该算法在求解高维优化问题时,易进入早熟状态,寻优结果精度较低。为此,文章提出一种改进的白鲨优化(improved white shake optimizer,IWSO)算法。首先使用Sinusoidal混沌映射初始化种群,以提高种群多样性及初始解在解空间的分布性;其次,引入鸟群搜索行为,赋予白鲨游动速度自适应动态惯性权重,以提高算法的收敛速度;最后,在位置更新阶段引入精英白鲨余弦变异策略,利用余弦函数的周期性特征,驱使白鲨个体在精英白鲨的有限邻域内进行精细化开发,以提高收敛精度。在23个著名基准函数和CEC2014函数上做了性能对比实验,其结果表明,IWSO算法优于6种对比算法,适合求解函数优化问题。
文摘Unlike consumers in the mall or supermarkets, online consumers are “intangible” and their purchasing behaviors are affected by multiple factors, including product pricing, promotion and discounts, quality of products and brands, and the platforms where they search for the product. In this research, I study the relationship between product sales and consumer characteristics, the relationship between product sales and product qualities, demand curve analysis, and the search friction effect for different platforms. I utilized data from a randomized field experiment involving more than 400 thousand customers and 30 thousand products on JD.com, one of the world’s largest online retailing platforms. There are two focuses of the research: 1) how different consumer characteristics affect sales;2) how to set price and possible search friction for different channels. I find that JD plus membership, education level and age have no significant relationship with product sales, and higher user level leads to higher sales. Sales are highly skewed, with very high numbers of products sold making up only a small percentage of the total. Consumers living in more industrialized cities have more purchasing power. Women and singles lead to higher spending. Also, the better the product performs, the more it sells. Moderate pricing can increase product sales. Based on the research results of search volume in different channels, it is suggested that it is better to focus on app sales. By knowing the results, producers can adjust target consumers for different products and do target advertisements in order to maximize the sales. Also, an appropriate price for a product is also crucial to a seller. By the way, knowing the search friction of different channels can help producers to rearrange platform layout so that search friction can be reduced and more potential deals may be made.