Satisfactions and stresses in the sorting of mail

Abstract

The effects of two types of letter-sorting technology on job stress and satisfaction were compared. Manual sorting, which uses the traditional method of assigning letters to classified pigeon-holes, was judged to provide elements of discretion, autonomy, and social interaction which are largely absent in coding-desk work, in which a keyboard is used to enter postcodes. Between and within-subject methodology was used in the analysis of data from those engaged in sorting (n = 160). In addition, these groups were compared with supervisors (n = 36) and engineers (n = 26) also working in the sorting area.

The key findings were: (a) higher levels of satisfaction were found amongst manual sorters and those spending 50–75% of their time in code-sorting; (b) stress is closely related to satisfaction in the code-sort group but not in the manual group; (c) in manual groups and in supervisors stress was manifested in fatigue, but in the code-sort group stress took the form of anxiety. The results are discussed in terms of the impact of the type of work on fatigue, as well as on job stress and satisfaction.     

On metric dimension of permutation graphs

The metric dimension \(\dim (G)\) of a graph \(G\) is the minimum number of vertices such that every vertex of \(G\) is uniquely determined by its vector of distances to the set of chosen vertices. Let \(G_1\) and \(G_2\) be disjoint copies of a graph \(G\) , and let \(\sigma : V(G_1) \rightarrow V(G_2)\) be a permutation. Then, a permutation graph \(G_{\sigma }=(V, E)\) has the vertex set \(V=V(G_1) \cup V(G_2)\) and the edge set \(E=E(G_1) \cup E(G_2) \cup \{uv \mid v=\sigma (u)\}\) . We show that \(2 \le \dim (G_{\sigma }) \le n-1\) for any connected graph \(G\) of order \(n\) at least \(3\) . We give examples showing that neither is there a function \(f\) such that \(\dim (G) for all pairs \((G,\sigma )\) , nor is there a function \(g\) such that \(g(\dim (G))>\dim (G_{\sigma })\) for all pairs \((G, \sigma )\) . Further, we characterize permutation graphs \(G_{\sigma }\) satisfying \(\dim (G_{\sigma })=n-1\) when \(G\) is a complete \(k\) -partite graph, a cycle, or a path on \(n\) vertices.     

Approximate sorting of data streams with limited storage

We consider the problem of approximate sorting of a data stream (in one pass) with limited internal storage where the goal is not to rearrange data but to output a permutation that reflects the ordering of the elements of the data stream as closely as possible. Our main objective is to study the relationship between the quality of the sorting and the amount of available storage. To measure quality, we use permutation distortion metrics, namely the Kendall tau, Chebyshev, and weighted Kendall metrics, as well as mutual information, between the output permutation and the true ordering of data elements. We provide bounds on the performance of algorithms with limited storage and present a simple algorithm that asymptotically requires a constant factor as much storage as an optimal algorithm in terms of mutual information and average Kendall tau distortion. We also study the case in which only information about the most recent elements of the stream is available. This setting has applications to learning user preference rankings in services such as Netflix, where items are presented to the user one at a time.     

Benchmark Dose Analysis via Nonparametric Regression Modeling

Estimation of benchmark doses (BMDs) in quantitative risk assessment traditionally is based upon parametric dose‐response modeling. It is a well‐known concern, however, that if the chosen parametric model is uncertain and/or misspecified, inaccurate and possibly unsafe low‐dose inferences can result. We describe a nonparametric approach for estimating BMDs with quantal‐response data based on an isotonic regression method, and also study use of corresponding, nonparametric, bootstrap‐based confidence limits for the BMD. We explore the confidence limits’ small‐sample properties via a simulation study, and illustrate the calculations with an example from cancer risk assessment. It is seen that this nonparametric approach can provide a useful alternative for BMD estimation when faced with the problem of parametric model uncertainty.     

Breaking the cycle of fear

Two approaches to eradicating pervasive and chronic fear include viewing mistakes and errors as informative rather than cause for personal evaluation, and improving people's skills for confronting and resolving these crucial conversations.     

Robust multi-criteria sorting with the outranking preference model and characteristic profiles

We present a new multiple criteria sorting approach that uses characteristic profiles for defining the classes and outranking relation as the preference model, similarly to the Electre Tri-C method. We reformulate the conditions for the worst and best class assignments of Electre Tri-C to increase comprehensibility of the method and interpretability of the results it delivers. Then, we present a disaggregation procedure for inferring the set of outranking models compatible with the given preference information, and use the set in deriving, for each decision alternative, the necessary and possible assignments. Furthermore, we introduce simplified assignment procedures and prove that they maintain a no class jumps-property in the possible assignments. Application of the proposed approach is demonstrated by classifying 40 land zones in 4 classes representing different risk levels.     

消化内镜护理风险控制中引入PDCA循环模式价值分析

目的探讨采用PDCA循环模式实施消化内镜护理风险控制后获得应用效果。方法选取2020年03月31日~2021年03月31日收治的80例消化内镜检查患者进行护理管理研究;随机分为常规护理管理组(常规护理管理)和PDCA循环管理组(PDCA循环模式管理),各40例;比较两组患者护理满意度(护理细节、护理质量、护理规则、护理严谨、护理态度)评分以及差错发生率。结果PDCA循环管理组护理细节(91.25±2.59)分、护理质量(91.33±3.02)分、护理规则(91.49±4.21)分、护理严谨(91.82±5.35)分、护理态度(91.96±6.03)分均高于常规护理管理组护理细节(79.31±4.06)分、护理质量(72.86±4.79)分、护理规则(79.66±5.23)分、护理严谨(80.19±6.52)分、护理态度(81.79±5.85)分(P<0.05);PDCA循环管理组差错发生率(2.50%)低于常规护理管理组(20.00%)。结论PDCA循环模式有效运用后,观察护理满意度以及护理风险差错事件发生率,改善程度显著,可促进消化内镜患者整体护理效果显著提升。     

The effect of vertex and edge deletion on the edge metric dimension of graphs

Journal of Combinatorial Optimization - Let $$G=(V(G),E(G))$$ be a connected graph. A set of vertices $$S\subseteq V(G)$$ is an edge metric generator of G if any pair of edges in G can be...     

管理熵理论--企业组织管理系统复杂性评价的新尺度

应用物理学、数学、力学、信息论、统计学和管理学等理论方法,提出了管理力、管理功和管理复杂度的概念、定义、基本原理和研究范围.基于管理熵理论的原理,建立了企业管理系统复杂性评价的新尺度和评价方法,构造了尺度的矢量空间、数学模型及量化模型.扩展了企业管理组织复杂性的研究范围.并进行了实例分析与验证.     

基于案例信息的多准则群决策分类方法

针对多准则分类问题中决策者难以提供分类模型参数以及多人参与决策的复杂性,给出了基于案例信息的多准则群决策分类方法.该方法首先根据效用函数分类模型的基本性质定义了案例信息的一致性,根据决策者的不同决策权重定义了案例信息的可信度.然后,建立整数规划模型从各决策者的案例信息中挑选出可信度最大的一致案例信息,并利用该信息和一致性条件对所有待评价方案分类.在分类过程中,直接利用案例信息分类,不需要设置分类边界参数.最后,通过一个MBA项目分类的实例说明了方法的可行性与合理性.     

基于动态因子Copula模型的行业间系统性风险分析

国际金融市场间的相关关系以及系统性风险受到很多学者的重视,本文则以我国股市的行业指数作为研究对象进行实证研究。通过构建动态因子Copula模型,文章对行业的日收益率数据进行了动态相关性分析,并基于风险预期占比度量了我国行业之间系统性风险的溢出效应。本文分析了2006年1月4日至2016年7月1日的28个行业指数数据,基于GAS动态负荷因子的变化路径来刻画其相关关系,通过风险预期占比来研究行业间的风险溢出效应。研究表明,各个行业指数收益率之间存在较强的关联性。就单个行业来说,化工行业与其他行业关系最为不稳定。就金融与非金融行业而言,金融行业对非金融行业的影响较大且较为平稳。本文所得研究结果可以为投资者和风险管理者在进行决策时提供一定的指导。     

The theory of the corporate life cycle

There appears to be a widespread management belief that the corporation is endowed with an inbuilt elixir for survival and growth, despite recent corporate declines.In this article, the author outlines and illustrates the operation of one of the newest theories on corporate activity—the corporate life cycle— and its use as a planning aid in determining where the company is and where it is going and as a relationary tool in predicting corporate trends for comparison with corporate objectives and the future operating environment.     

The theory of the corporate life cycle

There appears to be a widespread management belief that the corporation is endowed with an inbuilt elixir for survival and growth, despite recent major corporate declines.In this article, the author outlines and illustrates the operation of one of the newest theories on corporate activity—the corporate life cycle—and its use as a planning aid in determining where the company is and where it is going and as a relationary tool in predicting corporate trends for comparison with corporate objectives and the future operating environment.     

Assessing financial risks using a multicriteria sorting procedure: the case of country risk assessment

The assessment of financial risks is a problem of major interest for corporate entities (organizations, financial institutions, firms, etc.). The vulnerable economic and financial environments necessitate the development of operational approaches to measure and control financial risks. Most of the methodologies that have been proposed in the past employ a probabilistic notion of risk. This paper proposes an alternative approach to measure financial risks, considering their multidimensional nature. The proposed approach is based on the multicriteria decision aid (MCDA) method Multi-Group Hierarchical DIScrimination (M.H.DIS). The aim of the M.H.DIS method within the financial risk assessment context is to develop a set of additive utility functions that classify the considered alternatives (firms, investment projects, portfolios, countries, etc.) into predefined risk classes. The efficiency of the method is illustrated through a case study regarding the country risk assessment problem. Using the M.H.DIS method a discrimination model is developed that classifies the countries into four groups, and measures the corresponding creditworthiness and risk of the countries. Several validation tests are performed in order to compare the classification results obtained through M.H.DIS to the results obtained through multiple discriminant analysis.     

企业不同生命周期阶段智力资本价值贡献分析

通过采用VAIC和相关性分析及面板回归分析法,利用上市公司2002-2007年的面板数据,对企业不同生命周期阶段智力资本与企业绩效的关系进行实证分析.分析结果发现,在企业生命周期的任何阶段,智力资本对企业绩效都有显著促进作用;而在不同生命周期阶段智力资本不同组成部分对企业绩效的影响存在差异,其中物质资本和人力资本在各阶段与企业绩效显著正相关;结构资本只在成长阶段对企业绩效有显著的积极作用,而在成熟和衰退阶段对企业绩效存在影响不显著,甚至出现负面影响.结果也表明当前我国上市公司在资源利用上主要依赖于物质资本,而对人力资本的利用不够充分.     

消费者信用评估中的PCALWM方法研究

设计了一种基于主成分线性加权模型(PCALWM)的消费者信用评估方法,具有评估的客观性、可行性、适应性等优点。使用真实信用卡数据的实证检验表明模型分类效果比较好,具有较好的应用价值。     

Life cycle emission distributions within the economy: implications for life cycle impact assessment.

Refinements of methods for life cycle impact assessment (LCIA) are directed at removing unjustified simplifications and quantifying and reducing uncertainties in results. The amount of uncertainty reduction that is actually achieved through LCIA method refinement depends on the structure of the life cycle inventory model. We investigate the general structure of inventory models using an economic input/output (I/O) life cycle assessment model of the U.S. economy. In particular, we study the results of applying a streamlining algorithm to the I/O LCA model. The streamlining algorithm retains only those "branches" of the process tree that are jointly required to account for a specified fraction of the total impacts upstream of each point in the tree. We examine the implications of these "tree pruning" results for site-informed LCIA. Percentiles are presented for U.S. commodities and several important pollutants, for the share of total upstream emissions contributed by the set of processes in each supply tier, that is, each set of processes that directly supply inputs to another set of processes Capturing at least 90% of the total direct plus upstream emissions for criteria air pollutants and toxic releases for at least 75% of the commodities in the U.S. economy requires full modeling of direct emissions plus the first five supply tiers. The requirements for capturing a high percentage (e.g., >80%) of total emissions vary widely across products or commodities. To capture more than 60% of total emissions for more than half of all commodities requires models with more than 4,000 process instances. To well characterize the total impacts of products, life cycle impact assessment methods must characterize foreground process impacts in a site-informed way and mean impacts of far-removed processes in an unbiased way.     

连锁董事在企业集团知识扩散中的作用分析

在科学技术取得巨大进步的推动下,社会经济形态已经过渡到知识经济时代,知识成为企业最重要的战略性资源,企业的竞争性优势已不再仅仅通过充足的自然资源和产品生产来衡量.知识成为企业持续竞争优势的唯一源泉,而在知识扩散中,连锁董事起到了举足轻重的作用,他们为企业带来了先进的经验和值得借鉴的教训,让企业集团能够更快更好地发展壮大.本文在借鉴相关研究成果的基础上,致力于分析连锁董事在企业集团知识扩散中所起的作用,并试图给出一定的路径分析.     

Portfolio analysis and the product life cycle

This paper explains how the product life cycle and Boston Consulting Group's portfolio matrix can be combined to provide a more comprehensive framework for strategic analysis. The integrated model is more powerful than either concept taken separately because it provides an exhaustive system for classifying a diverse assortment of business units or product/market categories.