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171.
A portfolio forecasting model based on particle swarm optimization (PSO) algorithm with automatic factor scaling is proposed in this Article to effectively improve the accuracy of related analysis model in portfolio application. Firstly, the portfolio problem is analyzed and a hybrid constraint portfolio model is obtained by improving portfolio model with consideration of general portfolio model and combination of market value constraint and upper bound constraint according to Markowitz's theory. Secondly, PSO algorithm is introduced during analysis on portfolio model and solution is found with the hybrid constraint portfolio model of PSO on portfolio. In addition, in order to further improve the performance of PSO in model solution, automatic factor scaling is used for adaptive learning on parameters associated with PSO, to improve convergence of the algorithm. At last, simulation experiments show that the algorithm proposed can obtain a more ideal investment portfolio scheme, thereby reducing investment risks and obtaining greater investment returns. 相似文献
172.
While many scholars have demonstrated the effectiveness of theatre-based knowledge mobilization, fewer studies have examined its psychological dimensions. This article examines some psychological theories that may account for the success behind theatre-based knowledge mobilization. Drawing from the Canadian Experience Project, a study about the labor market challenges of skilled immigrant workers, we show how theatre-based research dissemination efforts attempt to achieve optimal stress by using aesthetic distance processes. We maintain that this psychological capacity to attune to audience members, especially evident in forum theatre, makes theatre a particularly effective means for knowledge mobilization. 相似文献
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采用康春花、孙小坚和曾平飞(2016)提出的等级反应多水平侧面模型探讨了评分者人数和项目个数对被试能力估计准确性的影响。模拟研究的结果表明:(1)随着项目个数的增加,估计值与真值之间的相关也不断增加;(2)评分者人数和项目个数在平均绝对偏差(MAB)和误差均方根(RMSE)上的主效应均显著,两者间的交互效应也显著;(3)简单效应分析发现,当项目较少时,3个评分者条件下的能力估计准确性最好; 随着项目个数的增加,4个评分者的估计误差迅速下降,且表现变为最好。 相似文献
180.
Communicators have at their disposal an ever‐increasing variety of modalities by which to transmit messages. Do the prominent norms attached to different communication modalities contain information in and of themselves? The present investigation considers this question through the lens of text messages and emails, hypothesized to confer different normative information about urgency. Text messages (vs. emails)—or any communication inferred by receivers to have been sent with greater urgency—cause the content of those messages to seem, in the eyes of receivers, closer in time (Study 1), closer in space (Study 2), and more likely to occur (Study 3). Moderation and mediation analyses confirm the role of urgency underlying the relationship between modality and distance. We provide evidence for these effects in a series of laboratory studies together with a field study in which real text messages and emails impact not only inferred distance but also a behavior deriving therefrom. Theoretical and practical implications highlight the importance, for both researchers and practitioners, of understanding how the medium of communication can shape interpretation of the message. 相似文献