Socioeconomic Index for Income and Poverty Prediction: A Sufficient Dimension Reduction Approach

The present paper introduces a novel method for the construction of Socioeconomic Status (SES) indices that are specific to a target variable of interest. It is based on the Sufficient Dimension Reduction (SDR) paradigm and uses a factorized model-based approach to simultaneously deal with predictor variables of mixed nature (i.e. quantitative, binary, and ordinal), which are usual in microeconomic data. These SES indices also identify relevant predictor variables using a two-step regularized matrix factorization approach. Using data from household surveys for Argentina (Encuesta Permanente de Hogares-EPH), the proposed method is compared with other existing dimension reduction algorithms such as standard Principal Component Analysis (PCA) and its version for mixed variables, regression on the full set of variables and Least Absolute Shrinkage and Selection Operator regression (LASSO).     

Synthesis of strategies in post-COVID-19 public sector supply chains under an intuitionistic fuzzy environment

Entities in public sector supply chains (SCs) often operate independently despite having interdependent objectives. Such a fragmented operational design poses several problems magnified by the presence of necessary public health measures fueled by COVID-19. This work contributes to the domain literature by introducing an overarching framework for synthesizing strategies in public sector SCs. The underlying component is the translation of information from the upstream to the downstream entities of the SCs, which is carried out by a Kano-enhanced quality function deployment. The proposed framework introduces intuitionistic fuzzy (IF) decision maps with the aid of the full consistency method to incorporate inherent interrelationships among strategies in the translation agenda. Under an IF environment that better captures judgment uncertainties, an actual case study of a multi-level public sector SC motivated by a government-funded project under the COVID-19 pandemic is demonstrated in this work. Findings of the case suggest that the government prioritizes meeting all project objectives. This requirement is reflected in the downstream SC. The project planning entity focuses on creating an overarching plan of operations, material request entity on complying with government procurement protocols, and maintaining public health and safety in operations for the procurement entity. Results show the effective synthesis of strategies across the SC, ensuring SC integration and collaboration. The case study demonstrates that maintaining public health and safety is a significant component of post-COVID-19 public sector SCs. Several practical insights on the synthesis of public sector SC strategies are also provided in this work.     

吸声材料在变频发电机组噪声控制中的应用

吸声是一种有效的降噪措施，吸声材料广泛用于各种机械设备及其部件的噪声控制中。通过对某1.7 kW变频发电机组的噪声进行测试，发现该发电机组存在原状态吸声材料降噪效果不佳的问题，25%～75%负载噪声仅仅降低了0.1～0.4 dB(A) ，在空载工况下，发电机组的噪声反而增大了1.1 dB(A)。通过更换4种不同参数的吸声材料进行对比测试，结果发现材质为聚氨酯、密度为35 kg/m3、厚度为10 mm的吸声材料降噪效果最好。与原状态相比，4种负载（空载、25%负载、50%负载和75%负载）下的噪声分别降低了1.1 、0.8、0.2 、0.6 dB(A)，发电机组的噪声得到了进一步改善。吸声材料的降噪分析结果为发电机组的噪声控制提供思路。     

Forecasting expected shortfall: Should we use a multivariate model for stock market factors?

Is univariate or multivariate modeling more effective when forecasting the market risk of stock portfolios? We examine this question in the context of forecasting the one-week-ahead expected shortfall of a stock portfolio based on its exposure to the Fama–French and momentum factors. Applying extensive tests and comparisons, we find that in most cases there are no statistically significant differences between the forecasting accuracy of the two approaches. This result suggests that univariate models, which are more parsimonious and simpler to implement than multivariate factor-based models, can be used to forecast the downside risk of equity portfolios without losses in precision.     

基于fsQCA方法的煤矿突发事件影响因素组态路径研究

为探究煤矿突发事件的发生机制，以40起煤矿突发事件为案例对象，结合事故致因“2-4”模型（24Model），应用模糊集定性比较分析（fsQCA）方法，识别煤矿突发事件的组态路径。结果表明，单个条件对煤矿突发事件的解释力较弱，但不安全物态、安全管理体系缺欠、安全文化缺欠和组织外部原因发挥显著影响。通过组态分析得到煤矿突发事件的3条路径，为煤矿事故致因领域的研究提供有益借鉴。     

基于概率分布的犹豫模糊集多属性群决策法及应用

因决策者本身对每个术语有不同的偏好，其做决策时可能会犹豫，决策结果会因人而异。针对智能物流实验室设备供应商选择过程进行决策分析,首先收集专家的犹豫模糊语言术语评价信息；其次综合评价专家的共识度和犹豫度确定其权重；再改进排序位置法，优化决策方法，提出一种鲁棒性很强的基于概率分布的犹豫模糊MULTIMOORA群决策方法。最后，通过对比分析验证该方法的有效性。     

基于五元联系数的水环境治理PPP项目可持续性评价

随着我国环境治理力度的加大,水环境治理PPP项目在基础设施建设中占了相当大的比重。但是,由于缺乏系统的指标体系、评价方法和考核工具,很难从理论上评判我国的城市水环境现状以及治理后的可持续性。借助集对分析理论,构建了基于五元联系数的水环境治理PPP项目可持续性评价模型,并选取许昌市水环境治理PPP项目进行案例分析。结果表明:项目整体可持续性较强,并存在上升的趋势,但项目公司管理可持续性处于下降趋势,应重点关注。运用集对分析模型,不仅可以得出项目整体的可持续性及趋势,也可以得出各评价指标的趋势,为项目提高或保持其可持续决策提供了依据。     

The valuation of barrier options under a threshold rough Heston model

In this paper, we propose a novel model for pricing double barrier options, where the asset price is modeled as a threshold geometric Brownian motion time changed by an integrated activity rate process, which is driven by the convolution of a fractional kernel with the CIR process. The new model both captures the leverage effect and produces rough paths for the volatility process. The model also nests the threshold diffusion, Heston and rough Heston models. We can derive analytical formulas for the double barrier option prices based on the eigenfunction expansion method. We also implement the model and numerically investigate the sensitivities of option prices with respect to the parameters of the model.     

Rational stability of choice functions

Two independent approaches have been used to analyze choices. A prominent notion is rationalizability: individuals choose maximizing binary relations. An alternative is to analyze choices in terms of standards of behavior with the notion of von Neumann–Morgenstern (vNM)-stability. We introduce a new concept ($r-$stability) that in turn extends the notion of stability and rationality. Our main result establishes that every rationalizable choice function is $r-$stable and every vNM-stable choice has an $r-$stable selection. An appealing property of $r-$stability is that well-known solution concepts (top cycle, uncovered set, …) are $r-$stable, while they are neither rationalizable nor vNM-stable.